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Engine Mount, Gear Legs |
General Quick (stupid) question. What's the thickness of the fuselage skins? the bottom forward skin ... 0,040 the forward side skin ... 0,040 the instrument panel skin ... 0,032 the side rear skin (vertical) ... 0,032 the rear rolled skins (bottom forward and turtle skin) ... 0,025 the bottom rolled end skin (tail leg support) ... 0,040 I hope it will help you. Petr Air Mixer Tom in your thread on air mixers on the firewall, both fresh and hot, you mentioned the T mixer. I am following your lead and plumbing off the engine baffle for cold air. My question, where do you access your hot air? Exhaust heat muff? If so where do you vent overboard unused hot air if full cold is selected on the T mixer? Maybe a picture of an installation would help. I intend to use the Van's t mixer inlets for hot and cold. Mind you I am not referring to the traditional box on the firewall. The object is to avoid duct cutouts on the aircraft sides. Best Howard ghrhodes@midsouth.rr.com On both rockets I have used the cold air off the back baffle to a "T". The T is a welded aluminum part, athough I have made one out of fibreglass. One outlet of the T goes to the heat muff. The other outlet goes to the mixer valve on the fire wall. The heat from the heat muff goes to the other side of the mixer. There is a hole that vents heat when full cold is chosen. This heat just goes into the engine compartment. During the warm summer months I take the heat muff, "T" and the mixer right off the plane. The cold air then goes directly into the plane. On the plane I am doing this time I am going to have independent hot/ cold systems. Nothing wrong with my current set up, I just like to try different things. Tom, I was talking to Dave Anders (of super fast RV-4 fame) about the plenum chamber on Dave Howe's Harmon Rocket. Mr. Howe apparently has a temp sensor in the plenum and is measuring 170 degrees in cruise flight. Now I was planning to get my cold air from the rear baffle as you suggest below, but now I am concerned that the air is going to be quite hot. Am I misunderstanding your comments? Do you find that the cool air from the back baffle is in fact cool? thanks, scot Scott Yes my air is cool, and lots of it. The only downside of this system is in case of engine compartment fire you do not have a source of fresh air. It is important to have some means of closing the air at the firewall for this reason. I do have the underwing air inlet for the rear passenger so we do have some alternate fresh air. When you land and taxi the air is slightly warm, but I crack the canopy on hot days for taxi and this gives lots of fresh air from the prop blast. Tom Martin I had the baffle pick-up on my -4, and I had to extend the pickup fwd to the inlet. I found out later that if you locate your pickup where the bugs hit the aft baffle, THAT air will be cool enough to use. No, I don't know where that will be on your plenum setup. Cheers Mark Hey Tom, ya ever get any fumes from the engine compartment? Like when you are #5 for takeoff and your tail is into the wind? I'm really liking this setup. Also, what size hole is sufficient for cockpit ventillation (I assume this later splits and feeds two vents). Thanks Eric Eric The only time I have had fumes in the cockpit is leaving oshkosh in 2000. I was downwind of a turbine lancair for an hour on the taxiway, man was it stinky! Tom Air Vent - Fresh What's the collective wisdom on where (and how) to mount the fresh air intake duct for the F1. Also any concerns over providing an exit or is the aricraft leaky enough that it's not necessary. Have a look at Greg Nelsons' ship -- those work fine as installed (in line with the cowl parting line). He also inserts his cowl hinge wires thru the scoops -- very slick! Get the parts from Van's, and cut the inlet opening 1 1/2" shorter (from the aft edge) than shown on the supplied cutout drawing . Tom Martin has installed an inlet on the LE of the rt root fairing -- likely this will work as good, and be less visible. No additional outlet area is required, but do NOT seal the baggage compartment completely! A seal at the track fairing at the apex of the aft skirts is recommended, at least for winter use (or high altitude use). As usual, there is some latitude here too. Cheers Mark Yep, those vents will blow your headset off , they work fine in that location and that's cut down as Mark said. I added a doubler around the cut out, not sure if that's required, but I do know there is some stress in the skin in that area. What do you think Mark? Peter? Is the doubler overkill? Greg Nelson Cabin air I must humbly disagree with Mark regarding the need for an outlet for cabin air. Getting air into the cabin is easy, you can use air from the engine baffle, NACA ducts on the fuse, a wing root opening, under wing NACA duct etc. In fact air wants to get into the cabin. There is a rather large volume of air that comes from the wing into the cabin floor area. I have flown rockets with this sealed and not sealed and the difference in the winter is quite noticeable. If you live in a cooler area you should put boots on the aileron push tubes as they enter the fuselage and seal the flap push tube openings. Now for getting air out. In all RVs it is just assumed that the air will go somewhere, and it does, but where? Would it not be better to direct this turbulent air in a low pressure area that would limit drag? There has been some experimentation with louvers and outlets on the aft fuselage, Bob Japundza please speak up, but I am not sure if any body has really got the right answer. I saw a post a while ago where someone had put a vent in the side of the fuselage, some production planes have vents for cabin air exist. May cars have vents in the rear door posts for this job. If we can find the right spot to let air out then we could use smaller inlet holes and heat from the front of the cabin would get to the shivering passenger in the back. Tom Martin Hi Greg! Any chance you can provide the suggested measurements for the openings? Thanks, Luis 21 I was just talking to a friend about this very subject, and thought when this beast flies, an easy way to increase outlet air/improve cabin airflow would be to remove the aft fuselage/elevator horn inspection cover. (Obviouly, the baggage compartment can't be too tight) There should be LOW pressure on the bottom side of the horizontal stab since it provides downforce, if my aerodynamic gray matter serves me correctly. If it improves flow, fabricate a new cover with vent holes/louvers, etc. Scott Roth Maybe a couple of those flying could give it a try and let us know... Hey Fellas: This is from the note I posted previously: Get the parts from Van's, and cut the inlet opening 1 1/2" shorter (from the aft edge) than shown on the supplied cutout drawing . Cheers Mark OK, so we cut the opening shorter at the front of the opening. Do we then move the fitting rearward so that we still have a smooth intake ramp? Hey Scott: BINGO!! That's why I don't seal the bottom area of the H Stab on any ships I assemble. Could be that a nifty louvered fairing could be molded to improve asthetics.... I had asked some RV types to try this area for venting, but I never recieved any feedback. I have not tried it both ways.... Cheers Mark Its pretty simple: cockpit - low pressure area tail cone - high pressure area Why? I don't know. Air is a funny medium. In the RV I get quite a bit of air that comes thru the openings around the baggage bulkhead. Enough that the canopy sides bow out about 3/16" in flight, and you can definitely feel air leaving around the canopy at a low velocity. I've tried sealing holes in the tail, have tried taping all the seams on the tail fairing, have tried louvers on the elevator inspection covers, tried taping closed the holes on the rear shelf, all to no avail. The only place left where air can come thru is the area where the elevator bellcranks are. There are some guys on the RV-List who have experimented further and cut holes in the belly in the tailcone to draw air out of the high pressure area by putting in reverse-facing NACA ducts with success. I've seen pictures of oil streaming around these vents; so, they do work to some degree. And I've noticed some certified airplanes with aft-facing vents in their fuselages presumably to let air out. Without a doubt I would recommend the aileron pushrod hole boots. When I put those in it cut down a lot of cool air entering the cockpit. And it don't cost nothin but your time to make them. I am going to cut a hole for a small reverse-facing NACA duct on the Rocket and try it, but it will be after I fly. I learned the hard way it is better to fly then paint than it is to paint before flying. I'm not sure if the Rocket is the same in this regard, it may not need it due to a more streamlined shape of the fuselage. Bob Cabin air exit management ideas My good friend Kent Paser, who built a Mustang II many years ago, spent more than 20 years thereafter experimenting with all sorts of drag reduction ideas on it including the treatment of exiting cabin air. Overall he added 64 mph to his top speed (starting from 170 mph). In 1994 he published a 170 page book detailing the results of many of his experiments titled "Speed With Economy" in which many pages are devoted to canopy sealing and treatment of cabin exit air. This is just one of the many, many areas Kent covers. His book is available from EAA HQ and is advertised in the Sport Aviation classified ads. (Bottom of page 140 in the September issue.) You won't regret spending the $29 it costs! Mark Yelich #86 I once tried using a simple hole with a leading fairing to make the hole opening face aft (not a NACA vent) in the bottom of the fuselage just ahead of the tail spring and got a load of exhaust fumes back in the cabin, so I'd be very careful in placing any vents on the bottom fuselage surface! Mark Yelich #86 I will measure my fresh air inlets and post it. I can attest they blow allot of air. I have no dedicated air outlet. I initially thought an air out let might be required, as my EZ needed one. I figured I could always add one to the rocket later if required. On my ship It does not seem to be required. I can close off the air inlets, then open them, noting the amount of air rushing in. If the air was chocking off some wear, I should see the air coming in slow down as the cabin pressurizes. I do not see anything of the sort. My conclusion is the air is getting out some wear, I really don't care wear. Now if you think your going to "accelerate" this spent cabin air back up to free stream speed or even something close to that, and reduce drag, I respectfully admire your enthusiasm for drag reduction, but seriously doubt if it can be done and be measurable. If you just dump it over board with out accelerating it, you are in theory producing drag, but theory and reality do not always agree. A back ward facing or Reverse NACA ducts shows a complete misunderstanding of how and why a NACA duct is designed. It may indeed flow air out, but it is not the most efficient shape for the job. A parallel sided ramp out let would work better for this application. . Greg Nelson My vents are located such that the cowl split line, if extended, would cut through the upper third of the NACA vent. The leading edge of the vent is 3.5 inches from the cowl line, and the vent it self is 4.0 inches long and 2+1/8 high. I angled the vents center line down approximately 2 degrees from level to better align with the local airflow. I ran the cowl hinge pin out the NACA duct, rather than out the front of the cowl as is conventionally done. To do this I had to epoxy in a short length of AL tubing to act as a guide for the pin so that it will hit the hole in the firewall needed for the pin to pass through. I used the vans plastic NACA vents, but cut the opening smaller, and it still flows more than enough. 2 inch SCEET connects to AL eyeball vents in the panel. The only flow control for the vent air is at the eyeball vents, and this is working fine. Greg Nelson I am sticking to Greg's recommendation as to no outlet. In a past post he addressed the correct exit shape, parallel ramp, if one chose to do it. Greg knows his topic, he is an Aeronautical Engineer and USAF test pilot. Correct me if I inflated or deflated your resume Greg. By the way, my experience with airflow in the F-1 is exactly the same as Greg's---you don't have to do anything special. I even installed a small fairing under the horizontal stablizer and still get no adverse pressure gradient, as I did in my RV-4 and RV-6. Who knows why. Adding a special duct is not a good idea in my opinion. Jim Cash, #10/Blackjack Hey Bob, I like your idea of boots for the aileron and flap pushrods. Did you make some, or buy something that worked/fit pretty well--like a shift boot for a car. Either way, let me know how you built and attached them. It gets a bit nipply up here in this frozen wasteland called Minnesota, and stopping that cold air from coming in would be nice. Thanks, Scott Roth I made mine just like these: http://home.hiwaay.net/~sbuc/journal/cold.html The aileron pushrod holes in the fuse are smaller on the F1 so yours would be smaller than they would on an RV. Bob OK, so we cut the opening shorter at the front of the opening. Do we then > move the fitting rearward so that we still have a smooth intake ramp? > No, trim the chord length from the aft (wider) end. Leave the nose section as is. Mark have used the sleeves from a tyvek paint suit to make my aileron boot covers. The material is light, cheap and does not restrict the movement of the stick. I fabricate a .025 ring and screw or pop rivet it to the fuselage. The other end gets held in place with a tie wrap around the tube. Tom Martin I'm considering an alternative to the fuselage/side placement for fresh air intake vents--by creating an intake opening inside the lower air intake opening of the lower cowling and running a duct to the firewall then on to eyeball vents inside the cockpit. There would appear to be plenyy of space inside the intake opening to locate an intake opening and the duct could be glassed to the inside of the lower cowling. Has anyone considered/tried this or have reasons to reject the idea. Thanks. I see two drawbacks, both of which can be overcome. Plumbing air from forward of the firewall into the cockpit can become an entry point for either carbon dioxide/monoxide or fire. You would want to plumb the air through a stainless steel mixer box that could be closed in the event of a fire. I guess I don't see the benefits of plumbing it that far forward versus running it off the side. It avoids the drawbacks described above. I intend to fabricate vent openings on mine that can be closed off flush with the side of the fuselage. It will have a NACA opening with a flapper door built inside of it. That way I can seal them off and get a flush outside look. Randy Pflanzer #95 sounds like you are planning to come thru the firewall with the fresh air vents if your intake in in the lower cowling. I would suggest you want as few holes in the firewall as possible. Thats what got Dalman with his engine fire. Vents in the cowling might look a bit strange also. I know we beat this to death a year or so ago on the list---everything is beginning to repeat. But again, Greg's location is exactly the same as mine and both work great---no fumes, plenty fresh air and its cold air. My ducting is only 12'' from intake to instrument panel outlet, and it will blow your headset off. Jim Good point -- you will need a shutter to enable you to close the thing off in the event of a fire. Make the shutter & all its parts from fireproof material too! Then, you have another thing to connect/disconnect every time you take the cowl off...tho you could engineer a self-sealing duct without too much trouble. The wingroot leading edge inlet sounds the best to me still. The inlet can be incredibly small to do the job, no CO contamination problems, and you never have to disconnect/reconnect in normal service. You would need an effective shut-off mechanism -- maybe a version of Cessna's upper windshield vents? Or, a twist-to-open cap like on the larger cans of spice? Mark Since it's said that the vents "blow your headset off", I thought dividing the flow from one vent with a "Y" pc of tubing would be the trick, but I don't see such tubing on the catalogues I visit. Hows this sound? Bob KISS principle---if you use the aluminum , Cessna type vents on the panel and NACAs on the side you have minimum resistance (12'' of ducting), and the vents fully shut off the flow of air (unlike the plastic type that Van sells.) Nothing has to be disconnected for engine removal, etc., and inside the NACA is an excellent place to put your OAT probe. Its also very light weight. Jim I like the idea of leading edge air vents. I really don't like the fuselage > mounted ones. If you could give me some more information that would be > great. Such as the position, area, shape, things such as that. I should be > ready to close the wings up here shortly and I am wondering if I could do > something like this with the bottom skin on or not. > Nah -- it's much simpler! We plan to cut a thumb size hole (`1" dia or so) in the LE of the root fairing, and attach some sort of hose flange inside the fairing, and route thesmall SCAT hose up the fwd side of the #2 bulkhead to the gaspers. Tom Martin tells us we will have to reverse the flanges of the T-005 fuel tank attach flanges to get enough room for the sidewall penetration. Piece o' cake! No wing mods that we can see -- maybe a nick out of the LE of the tank, behind the root fairing. Of course, if it actually WORKS, that will be good! ;-) I'll CC the F1 list on this one. Cheers Mark Re: NACA vents What is the purpose of shortening the Van NACAs? More air? Less air? More efficiency? Thanks Bob W Hey Bob: 1st reason is the hole is so big -- it deosn't need to be quite that large! Airflow is more than adequate. Cheers! Mark Hey Mark You didn't answer my question. Will I get as much air with the smaller hole? Bob The ship I flew had PLENTY of air (inlets on both sides), but it wasn't 95F/90% humidity. I think it approached the point of needing more outlet area, if all the vents are open at the same time. Pay particular attention to smoothing the inlet ramp, where it touched the alum skin. Small bumps here cost flow, and make noise. Jim Tufts had some strange happenings with his system from non-smooth edges and bumps in front of the vent opening itself. His wing vent would burble loudly at about 170MPH and quit completly above 190. He simply smoothed the inlet ramp, and reworked the edge of the fuel tank in front of the vent. The side vent wouldn't work at all till he smoothed out the inlet ramp edges. Cheers! Mark I can attest that you will get plenty of air from cut down side air inlets as Mark says. I even get good flow on the ground from the prop blast. They practically blow my head set off in flight, the flow is actually too strong in my opinion, even on a hot day. I think one of these vents could fuel two of the larger metal weymec vents, but the plumbing is simpler for each vent to have its own inlet. BTW I used a full size vans vent under the wing for the rear seat, and it is way to strong, I cut down the opining about half and now it's just a strong gale back there. I know having too much cooling air is like having too much horse power, but I'm telling you, its plenty as it is. Unless you like having a small tornado in cockpit with you then make them full size. Greg Nelson Thanks guys One more question. How do you keep the water out of them when parked? The flexible ducting runs up hill to the outlet in the cockpit. Water is not a problem. Greg Bill, on all three F-1s we have installed a NACA duct under the left wing near the wing root and ran a 3' section of 2'' ducting directly to a vent located above and to the left of the rear stick for fresh air. I have found that if you stuff the single heat muff with stainless steel ribbon it provides enough heat for front and rear cockpits even in Montana. I really don't like the idea of additional tubing of any type coming from the front. You have enough of that already. To me, there is nothing worse than a bubble canopy (greenhouse) on a hot day and min ventilation. I had a show quality RV-4 and finally sold it, partially because of the lack of ventilation. So, on this airplane I installed a duct on both sides of the fuselage, centered on the cowling halves just aft of the cowling (same as Greg Nelson described earlier). They work great with no fumes/gases from the engine. This allowed me to run a short 14'' piece of 2'' scat from the duct to a Cessna (Airline type) aluminum vent mounted on the lower left and right of the panel. These vents do not leak like Van's plastic vents, and you can adjust the amount of airflow. I can send you a picture of the panel showing the vents if you like. By the way, I used Van's plastic model in back, and it does leak a bit. Jim Cash The air vent itself came with the kit. It's the standard black 2" Vans unit. I mounted it next to the rear stick. I had to make a 2" hole in the fore/aft running floor beam to allow the hose to run off to the left to the big hole in the left fuselage side and then to the wing naca scoop. Basically the hose runs pretty directly from the eyeball vent to the scoop. Choosing a location for the eyeball vent was somewhat critical as everywhere I tried to put it, would bang into the stick or the flap bar. I mounted it to the pilots left hand seatbelt attach strap. I removed 2 rivets from that assy and replaced them with 6-32 screws that held the eyeball bracket in place. I have yet to figure out if I will ever be able to make a boot for the rear stick well with the eyeball vent and rear pax phone jacks mounted there. Tom - how has your fresh air intake in the wing root worked out? I would do almost anything to avoid cutting a hole in my fuselage for the standard vents. Thanks Bill Bill It is working quite well, I have never had a NACA vent in the side of my fuse so I cannot compare it to that but it is as good as the air I used to draw from the back of the engine baffle. The hole is two inches with a little lip on the top and I would not make it any smaller. The "lip" is really just an attempt to emulate something I saw on a cirrus. It covers about the top 25% of the hole and the line of it is more or less in the middle of the leading edge. I would say this lip is optional and probably not worth the bother. Without it you may consider a hole of an inch and a half, but it has more to do with hose availabilty than any issue with hole size. You will need to fabricate your tank bracket so that it attaches aft of the bracket on the fuel tank with it's flange facing aft. Then there is just enough room for the two inch hole. Tom Mark I have used the engine baffles to supply air to three of my planes. It works very well, is simple, and give lots of air. The only real disadvantage that I can see, and it is a big one, is that should you have a fire, or smoke, forward of the firewall you would have no other source of fresh air. I did not like the idea of cutting a NACA duct in to the side of the fuse so I experimented with a leading edge vent on my F1. This works quite well and supplies as much air as the back baffle provided. A downside is that it does take a bit of time to make the inlet in the root faring. Mark modified my idea and went with the "looks like two little gun barrel inlets" in his leading edge. I believe he told me that he should have increased the calibre size somewhat to get more airflow. There is nothing wrong with using the back baffle for fresh air if you understand, and can accept, the safety limitation of that system. I believe quite a few RV4s, perhaps most of them, use this system. Tom Martin Bill I still use the under wing air for the passenger, it is a must. If you use the baffle air you must incorporate a positive close valve on the firewall, it should be made of stainless steel, at the very least the flapper valve part should be stainless. I am not sure if the sliding canopy will depart the aircraft at low speeds. It would be safer to assume that it would and plan accordingly. I know that the flopper style canopies that I use would be gone, along with everything else in the cockpit! Not too many years ago a gentleman by the name of Von Alexander, was killed in his RV8, the result of an in-flight fire. He departed the aircraft at over 200 feet without a parachute. If I remember correctly there was some discussion regarding the fact that he may not have intentioned on jumping but had released his seat belt to reach something and then was ejected due to a control input? There was also an in-flight fire the claimed the live of a rocket owner a few years ago. I am embarrassed that I do not recall his name. His engine did not have the double clamps on his fuel injector lines, there is an AD for this. One of the lines broke, causing a fire. He maintained flight till he got back to his airport. The firewall had by that time failed and he died later in hospital. I raise these issues not to be negative but to point out not only the danger of in-flight fires but that they have happened in our aircraft type. Tom Martin Air vent on center console. Perfect. It blows on my cahones and upward to keep me cool. Doesn't trip intercom squelch. At high cruise speeds, I can hear the air blast thru vent as I move the little butterfly valve. Glad I got this one right! Our leading edge inlets work pretty dang good too, except I would like the vents to deflect the air into my face better. We're going to try to make an angled adapter thingy to remedy this. Mounting the vent higher, or in the center on the angles area of the console, would also help this particular abberation. Using the LE inlets to feed vents in the center would also be pretty easy - I hadn't thought of that... Cheers Mark Thanks Tom. Excellent points. Safety needs to be a BIG consideration. Have you figured out if there will be moisture problems with the LE inlet? I wonder about the NACA vents and rain too? Mark S.
Baggage Compartment It wouldn't hurt to build a temporary floor but we used lots of pillows. Once you Finnish the baggage section you won't need the temp floor aft of the cabin. We put in nut plates to hold down the baggage compartment. Not easy squeezing the rivets along the longerons. We used a vice grip with a small piece of 063 to squeeze them. I may use clip on nut plates in the cabin for the floor. Battery I found a great source for batteries. These are late production 35AH AGM (Absorbtive Glass Mat) batteries. They fit the rocket perfectly, weigh 25 lbs. Much better than a gel cell. Cost was $39 each. Search the web for AGM batteries and educate yourself. You'll like it! They had 500 in stock. I bought 4. Sunn Battery Company Jacksonville, FL 904-354-4508 P/N PTU135 $32.95 + $6.00 S/H Battery Size U1 Regards, Bob Gross Digikey has these batteries ($52.00) which have a better Ah (amp/hour) rating than do the Concorde RG-25XC, and they weigh about 3/4 lb. more: http://rocky.digikey.com/scripts/ProductInfo.dll?Site=US&V=11&M=LC-XB1228P The RG-25XC is 7.5"x4.97"x6.61" The Panasonic is 6.43"x4.88"x6.89" The terminals are a little different but no big deal. I checked on the Odyssey battery, and yes its light because it only puts out 14 Ah. That could easily become a problem during a hot start or in the winter, so you do pay a penalty for the weight reduction (not to mention price, either.) Bob #80 Yep -- I went thru 2 RG25s real quick. The cheaper batts actually last longer for me (33AH), and cheaper seemed to work out better in this case. Both are RG technology as far as I know. I did have a prob in CA with a hot start. I suspect my alt is not holding up its end of the bargain -- Mr Voltmeter shows me 13.5V in cruise. Sounds a bit low to me. Experts? Is it? 13.5v is fine. What kind of starter do you have? The skytech starters are notorious for their current draw... the other thing I'd be doing is looking at your starter contactor and/or the wiring. Are there brass nuts/bolts on everything? Corrosion could be a problem too... If you look in the Aeroelectric book, he has some info on analyzing starter problems, ground paths, etc. Basically you take your voltmeter and check the voltage drop across the starter when cranking and that should tell you if things are kosher or not. One word of advice for you guys, use an el-cheapo battery (walmart garden-tractor variety) during construction and buy the real thing as soon as you're ready to fly. Regular chargers seem to dramatically shorten the lives of RG batteries, and if you care and feed them properly then you should never have to charge them with a battery charger (well, if you don't leave the master on overnight). Since I'm thinking about it now, Mark, how much of an effect on CG would there be if you used a very small battery on the firewall? My guess is you could save at least 15 lbs that way with a lighter battery and not having all that heavy battery cable, and your starting performance would be just as good since the battery now doesn't have to overcome the resistance of a long run of cable...if the CG thing could work then I'd say its certainly worth a try... Bob ----- The CG won't support such a change. Sorry!! Even changing to the smaller batt in the aft compartment is not a real good idea. Now, if you use an O-360 instead of the 540, it just might work... Cheers Mark Mark, I remember reading some wear that the sealed RG type batteries like 13.8 - 14.0 volts. 13.5 is pretty standard for the old tech lead acid as too much voltage on that type would boil the acid with hydrogen, and spill fluids, making a nice acid mess of everything. The RG should still charge at 13.5, but maybe not as fast or as full. Is your voltage regulator adjustable? if so bump it up to 14.0 I see 14.1 to 14.0 on my ship. Greg. Actually, the datasheet for the Panasonic batteries says 14.5-14.9 volts... I don't think there are fixed regulators that put out that much, but Van's sells an adj. regulator. Usually 13.5v is sufficient (my RV hovers between 13.5 and 13.8 with no problems, I have an internal regulator on the alt.) *but* since your voltmeter is in front and the battery is in back there may very well be a significant voltage drop at the battery. Bob What if you put the ELT and strobe pack on the back deck where the HS mounts? As it is right now, with full fuel and oil and the pilot, how far are we from the fwd limit? Bob I suggest that you talk with Greg Nelson -- his ship is all elec, with 2 batts etc. Sounds like he's done it right -- no need to re-invent ya know! I think he used 2 Oddesey batts where the single large one usually sets hence no real weight gain (or very little). I have already asked him to draw us up the wiring diagram from his ship -- I might want to go the same route myself. Cheers Mark Hey Mark, You wouldn't happen to know what stations the firewall and the battery box are off-hand? If not, I can measure them tonight...I'm gonna do some rough calculations to see what the effects on w&b are by putting a smaller battery somewhere in the center tunnel to see if this is doable. I understand what you mean about polar moment but I don't know much about how that would affect flying qualities. On the Digikey catalog page they show a 20 Ah battery that weighs 14.6 lbs...that combined with a 00 cable, eliminination of the starter contactor as Bob Gross has done (eliminating resistance) and I'd bet you'd have no starting problems and would shave upwards of 20lbs in the process...IF the CG works. Lemme ask you another question: on the F1, what dictates the forward CG limit, and how did you come up with the forward limit? Is there any wiggle room there? Bob ----- Boot Cowl How do you fit the boot cowl to the new windshield and still be able to remover it? As to your questions abt the boot cowl. It goes like this.... 1. fit slope w/s to lay on old uncut boot cowl. Boot cowl must be screwed down. 2. draw a line about 1.25" around the plastic w/s fwd edge onto the bootcowl. This will be your cut line. This distance is creating a flange where the fiberglass tapes will blend down to the edge of the boot cowl...smooth. Your distance is your decision, you might want more or less. 3. When you're sure, cut within 1/8" of the line and discard the small piece. You can't reuse it as it will be mangled from the snips. I used the round end of my belt sander to smooth and finish the newly cut edge of the bootcowl. It should look like a shark took a big smooth bite out of it. 4. buy a new piece of .032 to make a new "boot cowl insert" . This replaces th epart you tossed into the junk box. Rough cut it and put a nice curve into it similar to the piece you discarded. 5. Take this new curved part and slide it under the installed bootcowl. When it is positioned, trace the newly cut, curved edge of the bootcowl onto the part. 6. Remove the new part and cut near the line you traced. You'll need to sand up to the line to get those snip marks out. Don't forget to leave about a .040" gap between the parts so the paint won't chip during service. 7. All thats left is to make a doubler flange and put in flush nutplates and screw the whole mess together. Your bootcowl should back in business. 8. The newly assembled bootcowl should be darned rigid. Now it's time to apply the glass tapes. When the tapes are cured, you can remove the bootcowl and your done. The bond betweent the plastic/glass tapes and the newly and permanently installed bootcowl insert is VERY strong. Don't forget to have the canopy latched tight when you put the glass tapes on. On my ship the canopy latches pull pretty hard and would pull the w/s bow aft a bit. This caused the front edge of the w/s to lift a bit. I held the w/s down against the bootcowl with some two by fours and duct tape until the glass tapes cured. I should have fittied the w/s to the bootcowl with the latches pulled tight. Oh well... Failure to latch prior to glassing, may result in having a whole lot of stress on the glass tape bond area when the latches are subsequently pulled. After the glassing nothing moves on themy ship now when the latches are pulled, and everything is quite snug. How did you get the curve in the new cowl piece? I bought a 3 in 1 sheet metal machine from grizzly for abt $300. It has a shear, finger brake and slip rollers. Makes a nice bend. I also used it to but the bends in the fwd w/s side skirts (the ones that lay below the w/s and the longerons). Very handy tool! Regards, Bob Gross In the cowling attach hardware bag, there are two camloc fasteners. Where are they supposed to go? Thanks, Scott Roth Scott My guess would be for the oil cooler door. Tom Martin Yep, oil door. I only used one after re-inforcing the lower side of the door with carbon fiber. YMMV. Regards, Bob Gross Control Stick I'm fitting up the front control stick. Sitting in the airplane, the stick Randy, I left mine full length. I'm glad I did. At low speeds (below 140 knots) the controls are real light. At high My stick is 15" from the pivot to the top of the grip as was suggested by Jim Cash. Junk that aluminum as it is Hey Fellas: I assure you the alum sticks are strong enough, judging from the cheater bar I have to use to That's the way I put mine in. Also I cut off an inch and a half. I cut more off the rear stick as it hit the front Control Tubes Mark > Should the control sticks be vertical as well as the bellcrank when > intermediate tube is connected? If so 45 7/8 is about 1/2 inch too long. > Thanks > Bob > The stick SOCKETS should be vertical, and the elev bellcrank should be 90 deg to the elev bellcrank ribs (it will lean slightly fwd from true vertical). The intermediate tube cut length is 43 7/8". Weld the ends onto a tube that long. I hope this helps! Cheers Mark I understand that some trimming is required for the Aileron Control Tubes to clear the fuse and wing structures. Can anyone tell me how much trimming of the sheet metal is required for the Aileron control tubes to clear the outboard holes in the fuse as well as how many and how much to trim from the ribs in the wings? A pic would be great.............. Thanks, Chuck Aileron control tubesI needed to do this... About 1/4" on the lower edges of the wing root rib holes. The fuselage openings will need to be opened upward all the way to the lower AL angle edge. Warmest Regards, Bob Gross Aileron control tubesBob Gross is on the money with this one, that is exactly how much I had to remove on both F1s. Consider adding a control boot here while you are working in this area as it greatly improves the comfort of the cabin in cooler weather. Tom Martin Cowling Attachment Flange Mark - the bottom photo on p.180 (v2.20) shows the > doubler between the firewall fingers and cowling flange > extending out almost inline with the leading edge of the > fuselage skins. > > The 3/4" doublers supplied with my kit are not wide > enough to achieve this orientation and extend only 1/16" > past the end of the flange fingers (when positioned for > good nutplacement support) and ~1/4" short of the fuse > skin edge. > > Is is necessary for the doubler to be as in the photo? > Does it have an effect on cowling attachment? Easy > enough to cut some wider ones. > > Thanks. > > Bill Really doesn't matter too much. The cowl butts up against the fuse skins so you don't see if the shims are even with the fuse skins. I did mine a little different--I used .063 strips for shims that I sheared, and in some spots, I used a combination of .040 and .025 where the firewall fingers fit better against the fuse skins. This was so I can have more meat on the fiberglass where you have to lay up some glass along the edge for camlocs so they won't deform as much when they're tightened down. Also trimmed the fuse skins to be parallel with the rivet lines. Everything came out looking pretty good, no puckers on the side skin rivets, etc. I can take some pictures tomorrow and send them to you guys. Don't worry if the flanges aren't exactly parallel with the fuse skins, you can put flutes in when you fit the cowl to get a smooth transition. Bob #80 RV-6 flying And Bob sees the focus! edge distance is a thing to watch (always) in structural applications, and it seems that trimming the side skins to be parallel with the rivet line will help in this situation too. Good comments, Bob. I await the pics to update the manual....(V2.21 will be out this month) Clear as mud? Mark. Guys, Can somebody tell me, please, the dimensions of the strip along the firewall that you attach the cowling to. Particularly the width and thickness, i.e. .025, .040 ??? Also, why are oops rivets called out to attach all the shims, flanges, etc to the side skins? Thanks, Vince Frazier This strip is .040 and it should stick out past the side wall by at least 1.125 to 1.5". The top piece can be installed easily the side pieces need a little work. As the firewall tips forward a little at the top you need to take a sliver off the top corner of the side flange. As well if you take a long triganular sliver off the bottom corner the thing will lay flat with the shape of the fuselage without the need for flutes. The oops rivets are used as the skin is not thick enough to countersink properly and retain edge distance. I used the 1/8" oops rivets here as they tend to pull the parts together better. Call me at 519-631-1369 if you have any further questions Tom Martin Hey Vince: We use 040 for both the flange and the shim there. Shim is 3/4-7/8 or so; flange is 2 1/2" if I recall correctly. You want 1/2" ED at the fasteners thru the cowling fiberglass, so the attach flange is fairly wide. > > Also, why are oops rivets called out to attach all the shims, flanges, etc > to the side skins? That way you can use 1/8" rivets at the flange where it attaches to the side skin -- more strength! > > Thanks, > > Vince Frazier > Vince You might considered using wider material for the shim and flange then those supplied with the kit. As I remember, that would have allowed me to have the shim up against the firewall in the back and up near the end of the sideskin at the front. I hate having flutes in the flange, but I didn't manage to get the flange parellel to the sideskin. The advice about taking off the aft end of the flange at the bottom of the sideskins to make the middle of the flange align with the sideskins sounds like good advice to me. --Thomas PS: It is pronounced "ya'll". Are you sure the fingers lay on the fuse skins exactly at the tangent of the radius in the bend of the fingers? If not, then the skin will get pulled in when you rivet and you will get a pucker around the rivet. I used the .063 to allow for thicker cowl fiberglass, by setting the attach flange in further away from the skins. I plan on reinforcing the cowl fiberglass a bit more than Mark specifies so it will take camlocs better. Bob I don't know if this is a re-hash of an old idea or not. It worked well for me so I'll share it. While fitting the boot cowl and all the cowl attach shims/flanges, I used some of the NAS rivets supplied in the kit as temporary fasteners. Pictures at this link http://www.iwantarocket.com/boot_cowl_stuff.htm. Terry Jantzi
Where are people mounting the permanent ELT Antenna? Mark suggests forward of the #7 bulkhead just to the right of the passenger's elbow. Van's factory demo mounts it in the VS back in the tail. What seems to be a clean location that works? Tom your input is always needed, I wonder what is in the water up north, it makes for excellent craftsmanship. BTW I have an Ameriking with a 23.75" antenna. Can the antenna be trimmed? Big No No? I mounted my antenna as mark suggested, in the cockpit forward of the #7 bulkhead. The tip of the antenna sticks up as high as possible without contacting the canopy. As far as triming the antenna, this is a question for the manufacturer. Tom Martin I mounted an Ameriking ELT with the ridged 24" long antenna in an antique biplane a few years ago. I called and talked to an engineer at the factory about shortening the antenna. He said if I cut the antenna exactly in half it would work just as good. He went on to say, I could cut it in half again but would lose some signal strength. I removed the ball from the end, cut the rod exactly in half and hammered the ball ( I mean reinstalled the ball). I can't say for certain if it works, but it sure looks better. Doug I looked a long time at different locations for the ELT antenna, and finally came up with a horizontal mount above the rear seat pan on the turtleback. It is out of the way and I would recommend it to everyone. Lui can scan a picture if anyone is interested. By the way I found an excellent place to put the ELT control head if you have panel space problems (which we did on this last F-1). I mounted it on the upper part of the turtleback (looking from front seat to the back) on the left side just outside the rear seat right shoulder harness exit. You can clearly see it from both cockpits, and it deletes having to route the control cable all the way to the front if it is panel mounted. I also put the antenna up there horizontally, and it shortens the distance for the antenna cable also. I'll let you guys know if I get away with this when the FAA comes. (HA) Jim Cash I was thinking that the ELT (3lbs) could be easily mounted on the bottom surface of the rear of the upper (rearmost) baggage compartment panel. This would move the ELT 28" farther back (my ELT has a remote switch). This would also free up the area of the ELT tray for things like a remote fire extinguisher bottle and possibly a remote oxygen bottle. In the (unlikely?) event that the combination of these things moved the C of G too far aft, a lighter RG battery might be a possibility. Dave Re: Number 12 F-1 passes with flying colorsDave, I have been very happy with mine mounted on the right side of the battery tray just behind the seat, and under the floor. If you mount your control head just to the right of the right rear seat shoulder harness exit on the turtleback, the antenna and control cable routing is greatly simplified. Jim Cash Just one small consideration that went thorough my head when deciding on ELT mounting; the unit I have is quickly removable and has a spare antenna to effectively make it into a hand held ELT. I decided to mount it on top of the forward luggage tray for quick access in the event of a crash. That way I can get to higher ground or begin a hike out for help and still be trackable by SAR. The remote control is still mounted on the right switch panel and the cables come through a grommet hole on the floor of the forward luggage tray. Takes 3 seconds to disconnect it and run from a potentially burning plane. I used the "ELT " tray to mount my strobe power supply. Just some random thoughts of a neophyte, scot While we're discussing ELT's have any of you "listers" opted to go with a 406 MHz ELT? Does anybody know of a good source? As I understand it, the 121.5/243.0 ELT will be phased out by 2009. (See attached PDF file) More info is available at: http://www.sarsat.noaa.gov/ Mark S. (#31) My ELT is also removable for hand-held use, but I figured that if I "landed" hard enough to set off the ELT, I probably won't be in good enough condition to grab the unit and make the dash. But I can always hope...It's along the lines of CONTROLLED bailouts and ejections--they are very, very rare. Scott I'm reaching waaay back into the memory banks, but I think it only takes around 5 G's to activate an ELT. The human body can handle a lot more than 5 G's in the front-to-back (parallel to the longitudinal axis of the aircraft) direction. So...if you can make it a semi-controllable "event," that portable ELT may do you some good. Tim You're absolutely correct. I think the specs for mine are less than +/- 3g's longitudinal for activation, and the 'ole bod can take somewhere around 40-60, or more, for a fraction of a second (I think). Let's hope we don't have to try out these ELT's. Scott ELT Mounting Plate Since I can't post pictures, you might try going to Thomas Linscomb's web site at this URL for a start: http://wnt.cc.utexas.edu/~jencole/elt/elt.htm Thanks Thomas! Mark S. And I hate the way I finally did the ELT tray. Instead of butchering the front quarter of the tray the way I did, I would suggest using a hole cutter for routing the battery cable conduit. This has certainly been on my "do over" list. I did not make any provision for AP. --Thomas Flap Actuator My the electric flap actuator is different than that > shown in all the photos - the pot is aligned with the > long axis of the actuator and it's all black. I assume > they have changed the style - correct? Yep - the actuator will attach to the #7 bulkhead, and act directly on the flap bar. EZ install... AND! I think I found the problem with the proto, so once that gets re-worked & apporved, I'll be shipping the kits out. Yep - the actuator will attach to the #7 bulkhead, and > act directly on the flap > bar. EZ install"... > > ----mean that I don't need all the linage described in > the manual? If so - how about an attachment drawing or > photo. > Hey Bill: The Mk.2 actuator will install quite differently than the one shown in the manual. I don't have a complete system on hand yet, so I can't give exact install dims. I can say it will also affect the rear seat installation, as the flap bar will install slightly aft of the seat attach area, causing a mod in this area also! Stay tuned -- as soon as I have the proto back in the shop I'll finish the install on 084 & update the manual. Cheers Mark do other bulders know of this change? - would be > a real bummer to compete the rear seat and linkage > assemblies (as I almost did) and then find out that the > actuator attaches much differently than described in the > manual. I trust I am not the only QB kit with the new > style actuator. > Hey Bill: No -- seems we made that change around #080 (Bob Japundza) or so -- basically, anyone without a flap bar will get the new system. I thought I explained that long ago...but just in case: TO ALL BUILDERS: IF YOU DO NOT HAVE A FLAP BAR, YOU WILL BE SUPPLIED WITH THE Mk.2 VERSION OF THE FLAP OPERATING SYSTEM. DO NOT PROCEED WITH THE INSTALLATION OF THE FLAP SYSTEM AS NOTED IN THE MANUAL. IT IS ALSO ADVISABLE TO WAIT WITH THE ASSEMBLY OF THE REAR SEAT BACK UNTIL THE FLAP OPERATING SYSTEM IS IN PLACE, AS THE REAR SEAT SUB-ASSEMBLY MAY BE IMPACTED BY THE LOCATION OF THE Mk.2 FLAP OPERATING BAR. Did I send you the old flap drive bag by mistake, or did you go get all that material yourself??! Cheers Mark Flap Bar/New Style On a related note, I installed the Mk. 2 flap bar and motor in my ship last week. I'm a little concerned about the strength of the back seat bulkhead where the end of the flap motor attaches. It seems to me (armchair engineer) that all the forces exerted on the flap bar will be transferred to the airframe at this point. Even with a reinforcing plate per the plans, this location seems a little flimsy. I think it would be appropriate to install a reinforcing rib to transfer this load to the longeron. Has anyone else looked at this? I don't want to reenginner things, but this just doesn't look right to me. Randy #95 Hey Randy, The RV-8 is set up exactly the same way and they don't have problems. Bob Randy, I installed a gusset on the center stringer at the #7 bulkhead (both sides), just like the one above it on the longeron. I did this long before I even saw the Mk 2 flap installation, and it stiffens up the bulkhead significantly. Scott Roth Foot Well (heal buckets) Construction. Mark Expanding the pics in Fuselage V 2.2, pg 156-7: appears that footwells shown have flush rivets w/~ 2" spacing on the heelwell sides and the flanges are flush riveted below the floor panel skin -- correct? The flanges could be trimmed to ~5/8" to allow for rivet ED. Dave Bockelman F1 046 A bit closer might be better -- maybe 1 1/4" or so... > The flanges could be trimmed to ~5/8" to allow for rivet ED. Correct. Mark Firewall Fuel Fitting Anyone, Where does the fuel line bulkhead fitting penetrate the firewall? Loren Harmon s/n 76 DrI put mine in the center below the engine mount cross tube. Don't put it too low though as the fuel line will fight with the vetterman exhaust hangers. Regards, Bob Gross Loren, I asked the same question some time ago and got a vague answer: in the middle, down low. However, when you do that, be careful so that it doesn't come out right behind a transverse pc of the mount. Mine almost did but I was saved by a angled bulkhead fitting. Would be nice to have a drawing of where to mount or penetrate the wall... Bob Hayner DrLorne Be careful not to mount the fitting too low. Ideally you do not want there to be a low spot in the fuel system that could trap water. Run the line straight forward from the boost pump. I use a bulkhead fitting at this location. Note that this is a good location to put a thick "washer" or spacer on the fitting to stiffen the firewall. Attached are two pics, I hope this is not a problem for people. Tom Martin Give yourself enough room to allow for a comfortable loop from the firewall DrI put mine in the lower right side (from inside view) and it is about 2" from the exhaust pipe. If I were doing Hey Bob, Something just occurred to me thinking about of your comments about the "spaghetti" in the fuel I think I just answered my own question: it costs $2100. Bob Fire Wall Insulation Is it necessary to insulate the fire wall to keep the heat levels under control, or does it stay fairly cool? If so, We use PN TRU-BLIP11406from Summit Racing, and use their "Sticky Stuff" to put it on. We do the fwd sides You do the fire wall too? Thanks, Scott You bet -- that thing gets HOT!!! You cannot do the sides of the rudder pedal box -- no clearance there... Hey guys, I just picked up some very thin "aluminized preox" nomex insulation from one of the race shops Hey Bob, You got a brand name or part number? Bob, I stuffed this e-mail away back in December because I knew that I would need it. Now I do and I have Hi Scott, I think this is the same material. It is an aluminized nomex fabric, the same stuff that is used for F1 List Uploaded FilesLui Here it is.........I used the 3M super 77 sray adhesive that comes out yellow. The brand name is Koolmat, Spruce carries it in the insulation section. I have templates of the areas covered if you need em Lui. I put the stuff in the fuel pump bay bay under the gages and sealed it with high temp sealer for a dry bay. The foot areas under the rudders now have it too under the carpet. BMA efis one should arrive next week, get the avionics wired and fired move this thing to the airport late sept or early oct plug in wings and guess what?????????maybe it will fly. Best H I have requested mark to fly first flight, the ski ramp for X games height attainment on rollout is still pending, I don't work wood very well....3 feet is nothin' on ole 84 lets go for 20 on young #3!!!!!!!!!!!!!!! Kool Mat on Firewall Kool Mat applied with high temp 3M spray adhesive. Mechanical fasteners back up the bond. The panel without Kool Mat will get some after possible firewall penetration. Stuff is good to 2000F. Jim Winings used some nice stuff on his firewall. Give him a shout. You can see what he used in the background of these pics. http://www.usi.edu/science/chemistry/vfrazier/2003-02-03/Jim's%20cooler%20mount. jpg http://www.usi.edu/science/chemistry/vfrazier/2003-02-03/fuel%20pump%20fitting.j pg I plan on using Firewall 2000. It can be found in the ACS&S catalog (2002 2003) on page 123. Loren Harmon s/n 76 Fuel System/Selector Is there any reason one cannot use an Andair fuel selector valve with left/both/right positions and leave it on "both" most of the time. I've flown my Cardinal for years with a Shadin flow monitor and the fuel selector set to "both" - greatly simplifies fuel management. I don't think you can use a "both with a low wing airplane Reed Somberg Bill, here is one area where I really agree with Van. You need to closely manage your fuel for a lot of reasons---wing balancing being only one. You will never see a RV with a "both" selection. I have an Andair with right, left and off on Blackjack and love it. Of course its your call, but I recommend you not install one with a both function. As you burn fuel this small airplane develops a rolling tendency quickly. Even with electric aileron trim I find myself changing tanks fairly freqently to keep the inbalance at a minimun. Jim Cash The reason why low-wing airplanes don't have "both" on the fuel selectors is it is nearly impossible to draw fuel in equal volumes from both tanks, so when one gets empty the pump will suck air and not fuel even though the other tank may be full. Gravity makes the difference in high-wing airplanes, which forces air out of the system. I have the Andair selector in my -6 and like it. I couldn't bear to put in the cheap valve that came with the kit, it looks too much like the valve for the ice-maker behind my refrigerator. All kidding aside, the Andair valve is a beautifully machined chunk of aluminium and I think that's why I like it so much. Bob Ok, my thoughts on the fuel selector. . On my RV4 I had to replace the unit after 200 hours as it started to seep a little. The internal parts are different now, there is now a teflon bearing surfaceand the detent is more positive. I have had no problems with the last three valves of this type that I have used on three different aircraft. The exact same fuel selector as is provided with the kit is in my 1976 Ford stake truck! And I can buy the same part at a local auto parts store off the shelf. I kind of like using parts that are readily available. The andair looks better, no doubt about it. Tom Martin They say.. Whoever they are that with a low wing airplane you will draw from Hi Bill, More on your fuel selector choice...in Canada, a homebuilt a/c will not be licensed if 1) it has a GlacierTo All I elected to use the supplied ice maker shutoff valve for the fuel system. Question to those that GlacierHoward They can be tough to get off, try a pair of locking pliers on the shaft, using something soft Hi all, Todays marks another small milestone in my Rocket' progress. The fuel system seems to be finished now. Other: JPI FS-450 fuel flow computer. Vans fuel pressure guage and xducer. Summit racing filters as shown I got back to the elect. fuel pump today and still no luck. I even checked to see if it was in backwards. I have Someting is definately wrong. Got the power polarity correct (Red plus/black ground)? Sounds like the pump is am now in the process of trying to plumb my fuel system. The builders manual is not very helpful on this subject. I have looked at various builders photos as posted but they all seem to hide at least one or more aspects of the job. Also, some of them don't have the Andair valve that I am using. It would be nice to see a set of plans or accurate and complete photos of the installation using the Andair valve together with the Aero Flow boost pump and single filter.Any help would be most appreciated!! I used the Andair valve and AirFlow pump. Also I used two inline filters, one on each side, before the selector valve. They were placed just inside the fuselage in the small wells so that they could be easily accessed for inspection and cleaning. Hey Guys, I have the inline fuel-filters in my RV-6 and wouldn't mount them inside if I can help it on the F1. It makes for a messy chore to clean them out if they're inside. My plan is to have them in the space between the wing root and the fuselage. The tanks have to be below the level of the fuel filters in order to clean them. Jim Winings told me the other day he was thinking about using an Airflow filter but wanted to weld a fitting on it to accept a quick-drain. That way is is just a simple matter of opening the quick drain and kicking the pump on to flush the filter. Bob #80 Bill, you share the same setup as I have on my F-1, and it works great. You will get up to a 28 gph fuel flow on takeoff, but the auto fliters will handle that. I found that there was room to install the filter between the fuselage and the wing (outside the fuselage) on the left side, but not on the right. My right side filter is installed under the floor on the far right side. System-One filters from Jeg's are used frequently on HR II's and the F-1 with good results. Jim "Also I used two inline filters, one on each side, before the selector valve. " Bill I too was planning on fuel filters between tanks and selector w/Andair valve and AirFlow pump , but moved fwd to past pump when Tech Counselor reminded me that would need 'empty' tanks to inspect filters. Filter is primarily to protect fuel injection, not pump, as I understand it. Pics can be made available if anyone is interested. Dave Bockelman F1 046 There is also a significant filter built into the Bendix injector housing (a finger screen). I was told the anything small enought to pass that screen will pass through the nozzle as well. I like the two filter idea. If one becomes clogged you have the other tank and its filter as a backup. Warmest Regards, Bob Gross Dave - You make an interesting point about servicing the in-line fuel filters. Since Airflow recommends filter before their pump - filters on either side prior to the fuel selector would appear easier to service compaired to a single filter between the fuel selector and boost pump as Airflow recommends. Compared to most of the things we attach to these toys, fuel filters are cheap. I was planning to also include a third in-line filter forward of the firewall before the engine fuel pump and injectors. When I'm satisfied that my tanks are free of any construction debris I will consider removing the two filters before the selector. Draining the tanks will be a hassle, but having seen some of the stuff that comes out of a newly constructed fuel tank, I wanted the added comfort of excessive compulsive redundancy. What about using a simple in line "safetyfied" on-off valve in the wing root fuel line before it enters the fuselage? Bill Gang, I want to install a nice Andair fuel valve, but don't know if I should get I used the Andair with the male fittings for the reasons that Bob cited. I hope to avoid any 90 degree fittings in the fuel system, although I "think" it only matters that you avoid 90 degree fittings downstream of the fuel pump. Randy #95 Hey Fellas: I'm told the culprit is the entry port at the mech pump: use a straight fitting here, and a hose 90 to keep the flow from cavitating. One of my pals in PHX had a vapor lock problem, and made this mod -- problem solved. No reported problems in the selector valve area to date -- could be a heat issue too... Fittings on the pressure side generally don't give problems. Might be a good idea to use a hose 90 at the firewall fitting too....Cheer Mark Fuel Vent Fitting Hi Fellas: I wrote the following to Don Swan regarding the vent lines. The lines aren't that hard to get right, but I'm not too fond of the outlet location for the reasons outlined. Do any of you engineer types have any input as to a better (and easy) vent outlet location? Cheers Mark "The vent lines run in and up the #2, and then back down out the belly. In reality, a better place for the vent outlets would be aft of the pax compartment, but that plumbing is not too easy. The problem is the flap push tube opening in the belly is directly behind the vent outlet, and aerobatics do slop some fuel out, which runs down the belly towards the opening...you get the picture. Gas smell in the cockpit... Might be a goot thing to move 'em outboard somehow, or aft. Or, run a line down the gear leg, but then any overflow while on the ground will soak the tires....DAMN!!!" Yea, put positive "G" on the airplane and install the lines in the standard manner. It's worked well for several F-1s and 3000 RVs. I've never had a gas smell in my cockpit, even in heavy turblence. Jim I ran the vent line up the #2 and then back out into the wing root. >From there I ran back to a hole in the lower wing root gap seal just in front of the spar. Jack #70 Mark, I remember you telling me about the potential problem with gas getting in the pit from the flap push tube, so what I did on my ship was move the vents inboard. The exits are in the inboard aft corner of the Pilot foot wells, and puts the vents just outside the slip stream of the exhaust. So far so good, no gas in the pit. I also put aero covers over the flaps so when they are up, there is no way air is getting in through the flap push holes. Greg Nelson Guys, In my experience any fuel that dribbles out the vent lines in flight streams towards the centerline of the airplane. The area directly behind the cowl outlet is a low pressure area, so in the stock location the fuel vapor getting inside thru the flap pushrod holes is unlikely. Jim is correct that it works well the way it is intended. One other thing I'd like to mention is there's been several cases in RV's where the fuel vents iced-up if they were made to pressurize the tank with ram-air pressure when builders cut a 45 on the vent. Cut the outlets flush and this shouldn't be a problem. In one particular instance the guy was out over the Atlanic in vfr conditions on his way to England. Regards, Bob Insulation & Sound Reduction The fuselage on #81 is nearing completion and I'm planning to install fabric covered side panels in the cockpit area. Would also like to insulate sidewalls and bottom to reduce noise level somewhat and provide some level of heat insulation. I'm considering the following products. 1. for firewall - "Firewall 2000 Ceramic blanket", Aircraft Spruce P/N FW2000. It's thin and easy to install with good temp rating. 2. for sidewalls and floors - 1/4" closed cell vinyl/nitrile insulating foam (meets FAR25.853b) Aircraft Spruce P/N 09-42720. It's light weight 2.8 oz/sq.ft., easy to cut to shape and can be attached with spray adhesives. Would appreciate hearing from anyone having experience (good or bad) with the following products -- or a recommendation for alternatives. Thanks. Bill Bill I used Kool Mat on the inside firewall and the same #2 closed cell foam product you are considering on the walls with fire retardant fabric from Boeing surplus in Seattle. I am pleased. I will post some photos on Chips site later today. The fabric and 1/4 stuff is glued to .016 AL backer. It is secured to aircraft side with flame proof Velcro from where else, Boeing, 2 bucks per pound of S^&**. The lightweight at all cost crowd will faint, but they can ride in their cold, loud tin cans while pulling away and laughing at me! Best Howard PS Aircraft carpet was dirt cheap too,,,,,and good looking. On my RV-6, I made my side panels out of insulating material that Van's used to carry. If was about 1/2" think insulation sprayed with a fire retardant and covered on both sides with foil. I loved this stuff because it was stiff enough to just glue your fabric to and then glue the panel to your fuselage. However, I can't find it anymore. I've ordered some stuff from Van's and Spruce but haven't found anything yet that I like. The current firewall insulation stuff that Van's sells is paper thin, looks like aluminum with an adhesive on the back. I've used it as a reflective material, but not much else. I'm still looking so I'm interested in what you find. Randy #95 Howard - how does one get in contact with Boeing Surplus or is that your private vendor? Summit Racing (www.summitracing.com) carries this material (TRU-BLP12406), along with some adhesive called "Sticky Stuff" (TRU-BLISS160Z-1). I'm not too sure the sticky stuff will work on the firewall in the case of a fire, but it's OK elsewhere. Use some aluminum tape to seal the edges of the insulator. I plan to use the 1/4" black foam. My buddy John Crabtree says that you can use the 3M spray adhesive to install... BUT it will soon fall off. He recommends using a product called "Shoe Goo" which comes in a tube and is available at Walmart, Shoe Carnival, etc Guys, McMaster-Carr has some adhesives that will withstand 2000 degree temperatures. It is the stuff they use to bond door seals on smelting furnaces. Comes in tubes, I think it was around $6-7/tube when I bought that stuff. Regards, Bob Vince, You have to use the right 3M adhesive. I got a can from Becky Orndorf when she did my seats. It was a different number than the 3M adhesive I could find at Lowes. For example, the stuff I found at the store said "#77" adhesive and Becky's can was "#74".....or vice versa. I can't remember exactly and I'm at work so I can't check. In any event, when I needed some more, I had to call her to get it. I removed one of my panels after they were installed. I had to destroy it to get it off. There was no way it was going to fall off and no way to get it to come off without distorting and bending it. So if you use the right stuff, the spray adhesive definitely works well. Randy #95 The 77 stuff is not that sticky. The #90 is the big boy.... Mark At your paint supply store look for the high temp yellow (color of spray gook) 3M can of stuff, don't know the number, I'll look. Best Plumbing & Other Systems. Mark - "plumbing diagrams" for recommended systems > routing (static, pitot, break, fuel, and elec) for > fuselage and wings would be most helpful for those of us > who have never built one of these things. Any chance we > could get the collective wisdom of others who have done > this before? > Good idea -- I'll put in my 2 cents worth. Other builder who have been down this path, please add your wisdom in here too. Pitot would run on the fwd side of the spar, most likely. Running this inot the fuse near the fuel vent lines would work fine. If you decide to run this line inside the wing conduit, getting it to the front side of the spar could be accomplished at the wing root, over the spar and just under the root fairing, and then follow the vent line into the fuse. The brake lines are shown pretty good in the manual - if you need better pics, please let me know! I have updated the fuel line pics in V 2.20, so you won't have further questions about those after you get that update. Elec: I don't have anything in the manual about that. Bob Gross' site shows a good basic install scheme, tho I think he used some additional equipment that some won't be using. I'll see about gathering some pics of a basic system, but we are leaving the elec design up to the builders, as all these ships will differ greatly in this particular area. Please follow std aircraft practices in any case! The Aeroelectric Connection is a very good book for reference while doing this elec install. Cheers Mark Is there any preference > or "best practice" for? > > 1. running static line from aft fuselage foward. Side > panels vs. floor? Was planning on left side below > engine controls. This run works good right below the top longeron. We'll see after Gen Jim runs his low-level test, but it may be that another OK place for the static is just in front of the #2 bulkhead -- right next to the instruments it serves! > > 2. running conduit for elec from tail light forward. > side panels vs. floor? Was planning 3/8 poly-flo run on > right side above rudder cable. Those wires will continue fwd inside the other conduit, which is on the left side. Might be better to put this run on the left too. Electronic pictures of this installation would be greatly appreciated -- I can put 'em in V2.21. V 2.20 should be up on the website this week. Cheers Mark Attached are 11 schematics from appendix Z of Aerolelectric Connection. Many options covered. The fuel schematic is from Airflow performance, the text description Mark gave on vents is helpful. One can order fuel level gauges from Chief made by ISSPRO that are read in E to F. These gauges are 33 to 240 Ohm Stewart Warner sender compatible and Van's uses them calibrated in gallons. The van's gauge starts reading when one goes below 15 gallons on a tank......not good for us. The Chief gauge is the same unit only E to F......Better. Hope this helps Best Howard I will have a complete set of customized electrical schematics for my F1 on my web site once I get the upgrade to TurboCad installed on my new PC and my drawings converted. Hopefully, they will be of some assistance to others. These were very helpful Howard. Thanks for sending them along. Randy Pflanzer I ran all my wires in a 3/4 inch OD poly conduit that I bought at the hardware store for about 5.00 total. Three 10 ft pieces did the trick. Static ports from the vans catalogue. Located aft of the #7 bulkhead and about half way up between the two longhorns, and plumbed forward with 1/8 clear plastic line to a junction behind the panel. Battery cables run along the inside of the two lower center longerons and through the spar section at the center break. Antennas located on the belly cables run forward in the same area. So far everything has gone through the center spar split without interfering with the controls. Fuel lines are obviously forward of the spar to the selector valve and then forward to the aux pump which is located just behind the firewall and between the rudder pedals. Hope this helps with your routing questions.. Larry #001 Hi Mark, Just to be different...I ran my #2 battery cable up under the port cockpit rail, secured with teflon hardware store clamps, to the firewall, where I mounted the starter solenoid. Took main power to the avionics buss off the hot side of the solenoid via #10 wire, with good results. Eric #45 Roll Bar I am fitting the front seat back supports. The plans call for this support to be I haven't done any research on accident statistics, but it seems that a tip-up and slide is a reasonable accident Dave, Like I said, one of the reasons I wanted to go with the tip-over canopy was the roll bar, although this
Rudder Pedals Can someone tell me how far the forward rudder pedals go into the foot wells so I can figure out the clearance needed for the cables on the rear pedals? Better yet give me the distance from the fuse side to the outside of the rear pedals. Thanks Bob W At full throw the ped is approx 1/2" from the firewall. Mark I know this is a solution to a problem that shouldn't exist. One of the Rockets in my shop is being outfitted with full dual controls. Of course that means rear passenger brakes as well. I think this aircraft is going to do training overseas in a country covered in sand. I was able to slightly modify the standard pedal with master cylinders. Pictures at Chip Gibbons site http://www.rocketclubhouse.com/member_upload_list_files.asp. Of course the downside to all this is extra weight and the danger of an overzealous "guy in back" applying brakes at a very bad time. But my customer has insisted, and it's going to happen. I was able to mount them a little higher so that when a size 11 foot is nestling in the foot wells, the brakes can't be touched. You have to move your heel up onto the floor to reach the pedals. The whole assembly is mounted on a sturdy angle which is bolted onto the spar through existing holes. I used a thick stainless hinge for all the articulating parts. I haven't decided whether to put the brake reservoir on each rear cylinder or to run two lines aft on each side. It is against my KISS rules, but the customer has last say. Terry Jantzi Seats Also - manual states "seats build to fit each ship" > which I assume really means to adjust height of front > seat back to fit the pilot within the boundaries imposed > by the top to the canopy. Short trying to measure from > my butt to my shoulders and guessing, can you provide > some general guidance on how to determine an appropriate > height for the front seat back? The seat has to be made to fit the cross bar -- that's all. The bar can be shifted slightly, or welded differently...quite a few ooptions there. Make the seat to fit the bar. > > Lastly - would appreciate some photos, drawings, and > tips on rear seat construction - the manual instructions > are to vague for us "newbies". > Agreed. We'll be working on #084 after OSH, so those updates will be in V2.21. Seat Belt Holes Hi guys, I am fitting my seatbelts and seats today. This is a dumb question, but having never acutally seen an F1/RV-4 before,.... Do the seat belts pass thru the front seat cushion thru a hole in the cushion? By butt is way wider than the fuselage seat belt attach brackets. Does one need to bend the seat belt attach flanges outward to get the belt to head in the proper direction? There is talk of making the holes in the seat back big enuf to allow the buckles to pass when the seat is folded fwd. When/why is the seat folded fwd? Regards, Bob Gross I put my belts through the seat back, and around the cushion. I've seen many variations, but I don't like the ones that go around the seat back, as it tends to fray the belts. I seldom ever fold the front forward, just for passengers with big knees, and it does not need to fold forward very much. Greg Nelson Another dumb question. Am I to assume that I must drastically shorten the fuselage seat belt attach brackets to allow the seat belt attach buckle to remain aft of the seat back? There is no mention of this in the assy manual. Right now my steel seat belt attach buckles stick straight fwd into the pilots back at lead 2". It looks a bit uncomfortable. Regards, Bob Gross I used 1 1/2" angle to make the front seat back side rails. This makes the seat comfortably wider and still leaves plenty of leg room for the GIB. This might not be an option for real F-1s with a slider... mine is a F-1H combo with a tip over. Might interfere with your prefabbed foot wells too... prefab.... (hysterical laughing on this end)... what's that? The wider seat is a bit more comfortable, IMHO, and allows the seat belts to move outboard a bit. I also bent the seat belt attach bars slightly. The best reason to make the holes in the seat back big enough to allow the buckles through is so you can pull the seat back out easily for those Oh-so-fun sessions on your back under the instrument panel. Yeah, I know the panel pops out and the boot cowl pops off... but how often are you really gonna do that just for a quick look? Of course, quick looks always turn into hours, hours into days, etc.... Hmmmm, sounds like a good reason to make the front stick removable too. Though I'm not actually gonna do it. I used to pull the seat back outta my RV-4 fairly frequently. You know what... camlocs on the instrument panel sound pretty good to me. Then you can open it soooo easily any time you want to. Vince I copied the RV8 holes. It seems that the belts end up coming out above the seat bottom cushion and under the seat back cushion. Bob W Spine Track In one place you say that the spine track ends just short of the #9 bulkhead > and in another place you say it should attach to the #9 bulkhead. I can cut > mine about 4" short of the #9 bulkhead. Which is correct? Either, actually. I was afraid somebody might cut it 1/2" too short (making a replacement necessary), so I mentioned to leave it long. > The UHMW slider block should be "drilled with a #9 bit." Why so when using a > -3 bolt? > That UHMW expands instead of cutting sometimes, like soft wood does. A #9 seems to actually cut a #12 hole. YMMV... Cheers Mark A dont blow it 'cause you can't drill it bigger once you drill it. The larger bits just spins and get hot as heck but the hole stays the same! Gotta use the right size bit from the start. Regards, Bob Gross Static Ports What's the collective wisdom on placement of static > ports? I was planning on two, one on each side of aft > fuselage, - like my C177. I think the major bugaboo is having a perfectly flush port. Seems it needs to protrude some. I put a cleveland port in my RV and there seems to be problems with it since it only protrudes about 1/64th, lucky me. I think you'll be fine as you are proposing as long as it protrudes a little. There has been many discussions on the rv list about this. Might be worth your time to go do a search on the archives. Hope it helps Eric My static ports are mounted at the same location on both sides. Before flying the bird I had a pitot static check done on the airplane. They checked the altimeter and blind encoder to 20K'. The airspeed indicator was checked in 10 MPH increments to 300 MPH. All was right on. So, even small errors would surprise me. My static is midway between the trailing edge of the wing and the leading edge of the stab, middle of fuselage. I used two, one on each side, ran the lines to a T, then up and around the turtle deck to keep water out. Seems to work OK, IAS a little on the slow side, but with in 10%. Don't know about the altitude. Greg G'day What you use for the static port itself can make a difference to the static pressure seen by your instruments - I recall a thread on the RV list some years ago comparing the variations between a "proper" port (machined item) to Vans recommended pop-rivet with the pin removed. If you check some piper, cessna or beech ports you will see some with a step just ahead of port to correct their under reading problem. Regards, Ron Graham Yes, about half way between the leading edge of the RV-8 tail horizontal stab and trailing edge of the wing---both sides. Sounds like Greg Nelson and I have the exact same setup. Jim Since I commented that the pitot-static test on my F-1 indicated little or no error in altitude or airspeed, I have been asked to pass on the location of my static ports. I installed two ports---one on each side about midway vertically on the fuselage. I don't recall the bulkhead number, but just in front of the bulkhead located at the rear of the luggage compartment is where the "T" for the ports is located. The ports themselves are just in front (cockpit side) of that bulkhead. Again, that bulkhead is approximately 18'' forward of the leading edge of the tail horizontal stabilizer. Another way to pinpoint the bulkhead that I am talking about is that it is the one located at the aft end of the canopy slide mounted on the top side of the fuselage. Hope this helps. Jim Cash FWIW. I used the pitot static on my Turbine Mustang and the faster I went the higher the altitude read-out was so I ended up with aft static ports. The F1 is not that much slower than the Turbine S51. Bob W Mark, I thought I answered this several times! DOH!! we installed the ports on Ole 84 just behind the firewall, and as high as practical. This put them in the area of: 3" aft of the fwd edge of the side skin 3" down from the upper edge of the side skin Basically, this is as far fwd, and as far up, as you can place them. We used the Cleaveland ports, whcih fit flush with the skin. By golly, with all the camera work I'll be doing with the new wings, I'll get a pic of the ports and put it inna manual. Cheers Mark
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