From: owner-krnet-l-digest@teleport.com[SMTP:owner-krnet-l-digest@teleport.com] Sent: Monday, June 15, 1998 8:30 PM To: krnet-l-digest@teleport.com Subject: krnet-l-digest V2 #96 krnet-l-digest Monday, June 15 1998 Volume 02 : Number 096 ---------------------------------------------------------------------- Date: Mon, 15 Jun 1998 09:50:50 -0400 From: Tom Andersen Subject: Re: KR: wing tank capacity Mark, I've wondered why a large space was left there. If I close that down to 1/2" I can get more tank space. I don't see any other reason for that space. - -Tom Mark Langford wrote: > TankHeads, > > I just whipped up a fuel tank (on CAD, it's at > http://home.hiwaay.net/~langford/48tank.gif) made from an RAF48 wing with > half inch thick top and bottom skins, and quarter inch front and back panels > which yielded an area of 108 square inches. Assuming you're down to 100 > square inches after adding baffles, fillers, sending units, and expansion > space at the top, that means you get a gallon for every 2.3 inches of tank > span (1 gallon=231 cubic inches). So if each of your tanks is 23 inches > long (which is just about right) you've got yourself a 20 gallon capacity > counting both sides. Of course, that leaves no room for aileron cables, > unless you flox a fiberglass tube in place for them to run thru. I offset > the front of my tank by making a triangular section for them to run thru, > and it didn't cost me much in total capacity. Mine are expected to hold > about 19 gallons, but I used the different airfoil (fatter), and only used > 18" of my wing span (improper prior planning!) thinking I'd need four inches > between my inner rib and the fuselage to operate the sanding board (dumb!). > Just trying to keep others from screwing up like I did... > > Mark Langford, Huntsville, Alabama > mailto:langford@hiwaay.net > see KR2S N56ML at http://home.hiwaay.net/~langford/kr2s.html ------------------------------ Date: Mon, 15 Jun 1998 10:21:19 -0400 From: Tom Andersen Subject: Re: KR: Re: elevator hinges John, What is the part number for the o*lite bearings from AS&S? I want to use them on my hinges. - -Tom John Bouyea wrote: > Haris > > I mentioned previously that Van's recalled such material when they supplied > it to their builders. I just purchased a partially completed project KR2 > with the RR supplied hinges. It appears to have the same hinge kit you > have described. Good enough for RR -> good enough for everyone else? I > don't plan on discarding these parts. > > I built the hinges for my KR2S project and found out about the non-radiused > material after the fact. I built 4 hinges for the elevator and 3 for the > rudder using the bearing material AS&S describes as oilite. The extra > hinges cost me about 40 grams plus the attaching AN hardware. I figure > this is good enough for me... > > John Bouyea > johnbouyea@worldnet.att.net > kr2s - building the spars > Hillsboro, Oregon > > ---------- > > From: HAshraf@aol.com > > To: krnet-l@teleport.com > > Subject: KR: elevator hinges > > Date: Saturday, June 13, 1998 7:23 PM > > > > Sorry to resurrect a twice dead horse. I have a set of rudder and > elevator > > hinges that I bought from RR. They are made of extruded Al that has sharp > > corners. I had mentioned this to Mike Mims and he even posted it on the > net > > but that did not evoke any response. > > > > I need to make a decision to have a new set made with the proper material > or > > use the one I have. Any suggestions? > > > > Thanks > > > > Haris ------------------------------ Date: Mon, 15 Jun 1998 10:52:11 -0400 From: Tom Andersen Subject: Re: KR: Stub Wing Fuel Tank Capacity Mike and Netters, I'm not familiar with the facet pumps. Are these things designed for 100% duty cycle? Can you leave them on all the time? If the facet pump pressurizes to say 5psi, and your engine pump pressurizes to 5psi, does that mean you'd have 10psi with both of them on? Does anyone know if the Soob pumps have a regulator? The Soob will have it's own pump, and a facet pump at the fuel valve from both tanks will be a backup pump. How do the Piper low-wing airplanes plumb their wing tanks? I know some Cessna's use a t-fitting connecting their gravity-feed systems, with only a shut-off valve in the main fuel line. I imagine that with two wing tanks you really want the ability to draw from left, right or both, plus a cross-feed system. Are the facet pumps reversible for use as a cross-feed pump? - -Tom > Mike Mims wrote: > I can understand why one wouldn't want the fuel in the cockpit with them but > I decided its not that big a deal. Seems that 80% of the homebuilt fleet > have the tanks inside or close to the cockpit. I would rather have a > gravity feed fuel system instead of relying on a fuel pump. Its just my > opinion but there is a much bigger chance of a fuel pump failing than the > fuel tank bursting. > zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz > Micheal Mims > SP290,.. Filling and sanding now! > mailto:mikemims@pacbell.net > http://www.geocities.com/CapeCanaveral/Hangar/4136/ > Irvine Ca > Fax 949.856.9417 > ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ ------------------------------ Date: Mon, 15 Jun 1998 11:45:09 -0400 From: Tom Andersen Subject: Re: KR: wing tank differential loads / Misc Info Jeff, Thanks for the IRL info. Are your wing tanks outboard tanks or stub tanks? I'd imagine that if the distance is 2x further out than a stub tank, a 3 gallon difference would pull like a 6 gallon difference in stub tanks. How far out are your wing tanks? Mark, Did that guy using wing tanks use them in the stubs? I would think that 7 gallons in the right stub only would offset the pilot weight in the left seat during solo operations. The pilot is centered about 9 inches from centerline @ 175lbs, but the fuel is 29 inches out at about 48 lbs (8 gallons). According to this I could have up to 9.05 gallons differential in the right stub and still be balanced during solo operations. - -Tom Jeffrey E Scott wrote: > >You guys who are considering building your main tanks in the outer wings > may > >want to get with someone who has done it before you make that final > >decision. There is a KR built just as Larry described at my airport (no > >header and main tanks in the wings) and the guy doesn't like it at all! > He > >has to pay real close attention to fuel management or the airplane > becomes > >severely wing heavy as the fuel burns from one tank. In fact he > dislikes it > >so much he is thinking of ripping it all out and installing a header > thank. > >He too has the back up battery and fuel pump and his little 1835cc VW > >powered retract KR2 weighs over 700 pounds empty! > >zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz > >Micheal Mims > > for informational purposes: > > I built my -2S with 7 gallons in either outboard wing and 9 1/2 gallons > in the header tank. > > I can run about 3 gallons differential between the wing tanks before the > plane starts to get a little wing heavy. With a full 7 gallon > differential between the wing tanks, the plane is very wing heavy, but > can be safely flown and landed. It just requires a fair amount of > aileron. This was tested during the flight testing regimen last year. ------------------------------ Date: Mon, 15 Jun 1998 11:45:18 -0400 From: Tom Andersen Subject: Re: KR: wing tank capacity Mark, Thanks! That's just what I needed! Incidentally, when I saw your drawing I realized that the bottom of my wing tanks will be slightly higher than the front in level flight. Of course, on climb-out the fuel will be deepest in the back, but I wonder if a rear-mounted pickup is still appropriate. Maybe a sump is needed? (Although protrusions are taboo). In fact, if the KR flies at .5 degrees incidence at the root, which we think it does, that would cause the same thing. Where is the pickup supposed to be on the plans-built-wing tanks? I'm real uncertain about using epoxy as a fuel tank sealer. Gasoline makes such a powerful solvent, and all it takes is a minor leak to require surgery. Welded metal seems so much tighter. Of course, two aluminum tanks would cost a lot more. Vinyl Ester resin is fuelproof, huh? - -Tom Mark Langford wrote: > TankHeads, > > I just whipped up a fuel tank (on CAD, it's at > http://home.hiwaay.net/~langford/48tank.gif) made from an RAF48 wing with > half inch thick top and bottom skins, and quarter inch front and back panels > which yielded an area of 108 square inches. Assuming you're down to 100 > square inches after adding baffles, fillers, sending units, and expansion > space at the top, that means you get a gallon for every 2.3 inches of tank > span (1 gallon=231 cubic inches). So if each of your tanks is 23 inches > long (which is just about right) you've got yourself a 20 gallon capacity > counting both sides. Of course, that leaves no room for aileron cables, > unless you flox a fiberglass tube in place for them to run thru. I offset > the front of my tank by making a triangular section for them to run thru, > and it didn't cost me much in total capacity. Mine are expected to hold > about 19 gallons, but I used the different airfoil (fatter), and only used > 18" of my wing span (improper prior planning!) thinking I'd need four inches > between my inner rib and the fuselage to operate the sanding board (dumb!). > Just trying to keep others from screwing up like I did... > > Mark Langford, Huntsville, Alabama > mailto:langford@hiwaay.net > see KR2S N56ML at http://home.hiwaay.net/~langford/kr2s.html ------------------------------ Date: Mon, 15 Jun 1998 08:49:42 -0700 From: Ross Youngblood Subject: KR: Flight Characteristics > Also just for comparison reasons, the CFI I was working with today has > also spent some time in an O-290 powered Lancair 235. She says the > Lancair has the more sensative elevator and that in her opinion, the KR > was easier to fly although she did chase it around a bit prior to some KR > orientation training. :o) > > I did let a number of kids fly the plane while doing Young Eagles flights > last weekend and found that they usually handled the plane better than > pilots that are used to grabbing onto a ham fisted air tank. :o) > > Jeff > ------- > Jeff Scott - Los Alamos, NM Jeff, I have flown a KR-like aircraft and I didn't think it was pitch sensitive, I think the word is resposive! I flew it with my two fingers and my arm in my lap. Just a touch to turn, but boy will it GO! Your post reminded me that I have flown in a KR-like aircraft, and didn't think it was pitchy at all at the time. However, I wasn't flying an approach. I have also had an opportunity to fly an RV-8, and a Arcoduster, both briefly, but if you are used to flying a C-152, then get into these, it's nice (at least it was for me), to have the plane go where you want it to when you want it to. The day after I flew in the Arcoduster, I was back to the C-140, trying to figure out how to land a tailwheel. I think if I tried to land either the RV or the Arcoduster, I would probably think they were pitchy too. -- Regards Ross ------------------------------ Date: Mon, 15 Jun 1998 08:51:21 -0800 From: Robert Covington Subject: Re: KR: RV-8 Accident >In a message dated 6/15/98 7:05:08 AM, you wrote: > ><the RV-8 prototype accident as yet. Anyone see an RV website where they're >talking about it? Maybe we can all learn something.>> > >It was a flight with two pilots on board. The Van's employed factory pilot was >taking a prospective customer for a cross country flight. Van was notified >immediately after the accident and he arrived shortly after the NTSB showed >up. A portion of the wing was found appx. 1/4 mi. from the crash site. Engine >was running upon impact. Two fatalities. Witnesses mentioned they "heard a >loud bang or pop just after they saw a portion of the wing separate from the >aircraft". Preliminary evidence indicates that the prototype suffered an in- >flight structural failure (evidence is pointing to the spar). The wing of the >RV-8 has been tested to failure with yield occurring somewhere around 10 G? >Other than that, most of what you're going to hear among the RV crowd is >speculation. There are many RV-8s currently under construction and Van is >working to determine if there is a design flaw that needs to be rectified >before many of these get in the air. Howdy. This was addressed at my recent EAA meeting by an RV-6 flyer (our Vice President); I don't remember if he had spoken to Van personally or not. It appears that the right wing came off (initial speculation points to a high-g maneuver) and that the new spar that they are using, which was of a cast single piece type instead of the usual laminated one, failed, basically crushing to pieces. He said that Van also found a cracked spar in another demonstrator RV-8 also, and grounded that plane. So Van is looking into the spar situation now to determine how to fix it and make things right. It was also mentioned that he will be shipping the fixes to all builders once the proper fix is found. That all depending on the final outcome/investigation. Makes me proud to be building a KR-2S, and bummed,(a real little bit) in that the RV-8 is the only RV I have considered building someday in the future. It looks pretty cool; I like the normal looking landing gear. ;) Robert Covington ------------------------------ Date: Mon, 15 Jun 1998 08:51:43 -0700 From: Ross Youngblood Subject: Re: KR: RV-8 Accident The word at our local EAA chapter is that VANS aircraft would rather not have people speculate. I have heard two different stories but in that light, I will wait until I hear somthing concrete. I personally flew in that RV-8 last summer, it was a wonderful aircraft. If I hear somthing concrete I will pass it on. - -- Ross Ed Janssen wrote: > Just curious - other than from the AVWeb, I haven't seen much discussion on > the RV-8 prototype accident as yet. Anyone see an RV website where they're > talking about it? Maybe we can all learn something. > > Ed Janssen ------------------------------ Date: Mon, 15 Jun 1998 08:56:47 -0700 From: Micheal Mims Subject: Re: KR: wing tank capacity Tom Andersen wrote: > I'm real uncertain about using epoxy as a fuel tank sealer. Gasoline makes such a powerful solvent, and all it takes is a minor leak to require surgery. >>> You seem to be making things way over complicated in an effort to make it safer. That doesn't compute! There are thousands of epoxy based fuel tanks flying on a daily basis not to mention hundreds of KRs with fuel tanks made with composite type construction. The plans say to install the pickup in the wing tanks at the aft end. ------------------------------ Date: Mon, 15 Jun 1998 09:00:29 -0700 From: Ross Youngblood Subject: Re: KR: Stub Wing Fuel Tank Capacity If you drive a car, you might be familiar with a facet pump... they are OEMed in many cars. I had a MGB with one, but this is hardly a recommendation for reliability, however the pump was never any trouble. They are designed for 100% duty cycle, and they pump to a specified pressure, then shut off. I believe the pumps might be rigged to give you 10psi, assuming they messure differential pressure between input & output, not atmosphere and output, but you would have to test this. Feeding one pump from another, and see if you get 10psi... otherwise, if you have two pumps on each tank feeding a main tank, I think you will get the lower 5psi number. (We used 5psi as a guesstimate). Looking at the pump, they look pretty robust, with no external parts to fall off break etc. I think it uses a silonoid, so there is a plunger that goes click-click when a magnetic field is switched on and off. I don't know how many years these will last, but they seem like they will go a long time before failing. The Facet pumps are not reverseable, and you would need to add some plumbing for a cross feed system. I have a 4 way valve, each wing is connected to a seperate Facet pump on seperate breakers, which feed the side ports of the valve. The header tank is gravity fed and makes the third intake. The gravity feed header tank, and the line from the 4-way valve to the final filter, then gascolator is 3/8". From gascolator to Ellison, and from the wing tanks and fuel pumps I use 1/4". So far the gravity flow seems to be pretty good at level attitude. - -- Regards Ross Tom Andersen wrote: > Mike and Netters, > I'm not familiar with the facet pumps. Are these things designed for 100% duty > cycle? Can you leave them on all the time? If the facet pump pressurizes to say > 5psi, and your engine pump pressurizes to 5psi, does that mean you'd have 10psi with > both of them on? Does anyone know if the Soob pumps have a regulator? > The Soob will have it's own pump, and a facet pump at the fuel valve from both tanks > will be a backup pump. > How do the Piper low-wing airplanes plumb their wing tanks? I know some Cessna's > use a t-fitting connecting their gravity-feed systems, with only a shut-off valve in > the main fuel line. I imagine that with two wing tanks you really want the ability > to draw from left, right or both, plus a cross-feed system. > Are the facet pumps reversible for use as a cross-feed pump? > -Tom > > > Mike Mims wrote: > > I can understand why one wouldn't want the fuel in the cockpit with them but > > I decided its not that big a deal. Seems that 80% of the homebuilt fleet > > have the tanks inside or close to the cockpit. I would rather have a > > gravity feed fuel system instead of relying on a fuel pump. Its just my > > opinion but there is a much bigger chance of a fuel pump failing than the > > fuel tank bursting. > > zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz > > Micheal Mims > > SP290,.. Filling and sanding now! > > mailto:mikemims@pacbell.net > > http://www.geocities.com/CapeCanaveral/Hangar/4136/ > > Irvine Ca > > Fax 949.856.9417 > > ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ ------------------------------ Date: Mon, 15 Jun 1998 12:06:09 -0400 From: Tom Andersen Subject: Re: KR: wing tank capacity Mike, It sure would be cheaper and easier to go with foam and glass stub tanks. The price is right! - -Tom ------------------------------ Date: Mon, 15 Jun 1998 09:09:36 -0700 From: Micheal Mims Subject: Re: KR: RV-8 Accident Robert Covington wrote: > Makes me proud to be building a KR-2S, >> > Robert Covington Gives you a little ammo next time you get snubbed by an RV builder eh? I hate to say it but I dont see hoe Vans is still around considering all these inflight spar failures. First the RV3 and 4 now the 8! Has there been an RV6 failure? ------------------------------ Date: Mon, 15 Jun 1998 13:10:15 EDT From: Kr2dream@aol.com Subject: Re: KR: fuel tank vent lines Dana: Before you mount the header tank - check it with real fuel instead of water. My tank held with both air and water but seeped when I put fuel in it. Fuel will go through some VERY TINY pinholes that air/water won't. You might save yourself some headaches. Bob lasecki Chicago - learning the hard way! ------------------------------ Date: Mon, 15 Jun 1998 20:41:14 +0200 From: aabbcc01@infonie.fr Subject: KR: Skunk Works Sorry but i don't understand well the american language ------------------------------ Date: Mon, 15 Jun 1998 15:10:39 -0700 From: Ross Youngblood Subject: Re: KR: Skunk Works aabbcc01@infonie.fr wrote: > Sorry but i don't understand well the american language No problem, I don't understand the American language very well either, and yourunderstanding of English is much better than my Understang of French, oui? ------------------------------ Date: Mon, 15 Jun 1998 17:47:29 -0500 From: "Mark Langford" Subject: KR: pickup location Tom, My fuel pickup is located in the middle of the wing, at the lowest point while at cruise (see http://home.hiwaay.net/~langford/wingtank.gif). I was able to do that because the NLF airfoil slopes up towards the trailing edge at an angle that approaches the angle that the plane stalls at. For this reason, my pickup is submerged at cruise or climb. But just for insurance, I built in a little "dam" (see the above picture) to catch more fuel when in climb, certainly enough for a good climbout. I also built a "trap door" from a piano hinge which allows fuel in but not out of my little "header within the tank" area which will help compensate for sloppy flying (ball not centered) or mild aerobatics. See http://home.hiwaay.net/~langford/kmarkl.html (the update) and the "Wingtank" area for more pictures and explantions... I've used a Facet pump in all my Weber powered VWs for the last 25 years, and only had one fail, but it happens. I'm using one in this plane as a transfer pump only. I believe they usually put out about 5 psi. My real fuel pump for the CIS will be a Bosch, which fails gradually with lots of warning. Mark Langford, Huntsville, Alabama mailto:langford@hiwaay.net see KR2S N56ML at http://home.hiwaay.net/~langford/kr2s.html ------------------------------ Date: Mon, 15 Jun 1998 17:47:26 -0500 From: "Mark Langford" Subject: KR: Bernie Warnke PropHeads, I ready last night in Sport Aviation that Bernie Warnke died in April. He's the guy who made the "almost constant speed" prop famous, mostly for VWs. That leaves a big hole in the prop department. Mark Langford, Huntsville, Alabama mailto:langford@hiwaay.net see KR2S N56ML at http://home.hiwaay.net/~langford/kr2s.html ------------------------------ Date: Mon, 15 Jun 1998 19:01:39 EDT From: BSHADR@aol.com Subject: Re: KR: Bernie Warnke In a message dated 98-06-15 18:39:53 EDT, you write: << I ready last night in Sport Aviation that Bernie Warnke died in April. He's the guy who made the "almost constant speed" prop famous, mostly for VWs. That leaves a big hole in the prop department. >> Mark: FWIW, I heard Bernie's daughter would continue his work (maybe like RR did after Ken's death) plus Bernie's ex-son in-law is using his designs too. Maybe Brian Whatcott will have more on this, I think I read it on one of the other lists that we are both on...Brian, yoo BRIAN, got your ears up? Lil' help here please... Randy Stein flames to: BSHADR@aol.com ------------------------------ Date: Mon, 15 Jun 1998 19:35:22 -0500 From: Bobby Muse Subject: Re: KR: fuel tank vent lines At 08:22 PM 6/13/98 -0700, you wrote: >What size vent line are people using? My system is plumbed with 3/8s line >but that seems a little big for a vent. I need to install a vent in each >wing tank and one for the header thank and was thinking 1/4 inch would be >fine. Thoughts? >zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz >Micheal Mims >S Mine's 1/4". Bobby Muse(N122B) mailto:bmuse@mindspring.com Wimberly, TX ------------------------------ Date: Mon, 15 Jun 1998 19:35:24 -0500 From: Bobby Muse Subject: Re: KR: fuel tank vent lines At 10:15 PM 6/11/98 -0800, you wrote: >Mike > >I used the 3/8 size in mine, and by the way be sure to install a check >valve if your header tank vent is on top (infront of the windshield). >I forgot to do that on mine and the first time I stalled the bird fuel >sprayed out the vent all over the canopy. >Parley N54PB > > > >On 13 Jun 98 at 20:22, Micheal Mims wrote: > >What size vent line are people using? My system is plumbed with 3/8s line >but that seems a little big for a vent. I need to install a vent in each >wing tank and one for the header thank and was thinking 1/4 inch would be >fine. Thoughts? >zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz >Micheal Mims > Let me add to the info on my vent line. It is vented from the rear/top of the header tank, and the vent line exits the KR under the KR just forward of the main spar, bent forward and flaired as to pressurize the tank. I epoxied some alum. screen from the hardware store to the flaired end to keep the bugs out. Bobby Muse(N122B) mailto:bmuse@mindspring.com Wimberly, TX ------------------------------ Date: Mon, 15 Jun 1998 18:34:57 -0600 From: jscott.pilot@juno.com (Jeffrey E Scott) Subject: Re: KR: Bernie Warnke You might also note that Bernies daughter is advertising in SA under the name Margie Warnke Propellors as she is producing a very similar prop and will probably assume the Warnke business (or may have already assumed it). She uses the same 1/16" laminated prop blanks and make a very nice prop. Bernie's son in law (or possibly ex-son in law?) is also building a very similar prop under the name Performance Propellors which is where I bought mine. However, Bernie was a pioneer in the area of advancing fixed pitch propellor design and will be sorely missed. Jeff - ------- Jeff Scott - Los Alamos, NM jscott.pilot@juno.com See N1213W construction and first flight at http://home.hiwaay.net~langford/kjefs.html & http: //www.thuntek.net/~jeb/krpage.htm On Mon, 15 Jun 1998 17:47:26 -0500 "Mark Langford" writes: >PropHeads, > >I ready last night in Sport Aviation that Bernie Warnke died in April. > He's >the guy who made the "almost constant speed" prop famous, mostly for >VWs. >That leaves a big hole in the prop department. > >Mark Langford, Huntsville, Alabama >mailto:langford@hiwaay.net >see KR2S N56ML at http://home.hiwaay.net/~langford/kr2s.html > > _____________________________________________________________________ You don't need to buy Internet access to use free Internet e-mail. Get completely free e-mail from Juno at http://www.juno.com Or call Juno at (800) 654-JUNO [654-5866] ------------------------------ Date: Tue, 16 Jun 1998 00:47:44 +0200 From: aabbcc01@infonie.fr Subject: Re: KR: Skunk Works - ---------- > De : Ross Youngblood > A : krnet-l@teleport.com > Objet : Re: KR: Skunk Works > Date : mardi 16 juin 1998 00:10 > > aabbcc01@infonie.fr wrote: > > > Sorry but i don't understand well the american language > > No problem, I don't understand the American language very well either, > and yourunderstanding of English is much better than my Understang of > French, oui? > > i agree your congratulations thank you (and mean to say you are not an american?) bye ------------------------------ Date: Mon, 15 Jun 1998 20:47:21 -0400 From: Donald Reid Subject: Re: KR: Skunk Works aabbcc01@infonie.fr wrote: > > Sorry but i don't understand well the american language You have nothing to be ashamed of. Your English is much better than ANY human language that I can speak. Computer languages are easy, French is hard. - -- Don Reid Bumpass, Va. mailto:donreid@erols.com KR2XL at http://www.erols.com/donreid/kr_page.htm Ultralights at http://www.erols.com/donreid/usua250.html ------------------------------ Date: Mon, 15 Jun 1998 20:50:35 From: Flesner Subject: KR: wing tanks At 01:24 PM 6~14~98 -0400, you wrote: >Larry, >What is the capacity of your wing tanks? Are they in your stub wings or in your >outer wing panels? >-Tom > Tom, I placed my wing tanks in the outboard panels. I built the stock length wing and the tanks are from the forward spar rear face and ten inches toward the trail edge.(roughly 4.5x10xwing length) They run from root to tip and have three 2 inch foam baffels with only a one and one half inch semi-circle opening for fuel to flow between compartments. There is a 1/4 inch vent from one bay to the next at the highest point to prevent air locks. The slosh holes are on the very bottom. I didn't want the fuel to flow from root to tip and back too quickly and get weight shifting. I installed the vent at the forward tip end just outside the fill ports. There is a drain at the inboard trailedge of the tank and the pickup is recessed in the bottom center at the root. Math tells me I have twelve and one half gallon in each wing. I use one flex hose at the attach point with metal fittings and the rest of the line is all 3/8 inch alum. I use two facet pumps in parrallel. The line from each tank comes in to a shutoff valve just before the pumps. I can pump from either tank or both with either pump or both and with both valves "on" the system will crossflow. I can shut one tank off if I want to manage wing weight just like I have to do in the TriPacer that has no "both" selection in the fuel system. Yes , my KR is heavy but it was not the fuel system that caused the problem. I could eleminate maybe 15 pounds by removing the second battery system, one fuel pump, one valve, and associated fuel line. With any kind of wing tanks you will need a fuel pump of some kind and my two wing tanks are maybe 30% heavier (W.A.G) then a 16 or 18 gallon header tank. I felt I needed more tankage than that with an 0-200. For those building header tanks, make sure you clamp down the line somewhere before the firewall and then install a pull-apart between there and the firewall. One KR accident report related a KR making a hard landing that caused the firewall to separate from the fuselage. the fuel line pulled the bottom of the tank out and covered the pilot with fuel. How LUCKY he was that it never ignited. For Jeff, what was it the pilot at your field disliked about wing tanks? If there is something I should know , please tell me. I've never heard a Cessna, Piper, Bonanza, Rockwell, Mooney, Ercoupe, etc. driver say they wished they had their fuel in the cockpit !!!!!!! Larry Flesner P.S. you fellows with wing tanks and only one pump might want to do a weight and balance with fuel only in the wings and the header near empty. Steve Altman (sp) from Colorado had his pump quit on the way to Rrough River and said he was getting pretty tail heavy by the time he landed. You may want to land and transfer fuel if that happens. One more thing to think about !!!! ------------------------------ Date: Mon, 15 Jun 1998 20:08:48 +0000 From: Great Plains Aircraft Subject: Re: KR: RV-8 Accident also heard that the dan denny thunder mustang suffered a similar inflight failure - pulled the wings off- anyone hear about this. steve ------------------------------ Date: Mon, 15 Jun 1998 21:09:08 From: Flesner Subject: Re: KR: fuel tank vent lines ===============snip================== >You guys who are considering building your main tanks in the outer wings may >want to get with someone who has done it before you make that final >decision. There is a KR built just as Larry described at my airport (no >header and main tanks in the wings) and the guy doesn't like it at all! He >has to pay real close attention to fuel management or the airplane becomes >severely wing heavy as the fuel burns from one tank. In fact he dislikes it >so much he is thinking of ripping it all out and installing a header thank. >He too has the back up battery and fuel pump and his little 1835cc VW >powered retract KR2 weighs over 700 pounds empty! >zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz >Micheal Mims Sorry Jeff, I should have directed the question to Mike. Was it only the wing heavy problem that he didn't like ? That could be corrected with a both setting on the fuel selector. Also, fuel in the outer wings helps to "unload" the wing attach fittings. With my tanks so close to the C.G. I will get very little weight shift with fuel burnoff and what shift I do get will be forward , not backward. Larry "everyone thinks they have a better idea, don't I ?" Flesner ------------------------------ Date: Mon, 15 Jun 1998 19:16:17 -0700 From: Micheal Mims Subject: Re: KR: wing tanks At 08:50 PM 6/15/98, you wrote: >For Jeff, what was it the pilot at your field disliked about wing tanks? >If there is something I should know , please tell me. I've never heard >a Cessna, Piper, Bonanza, Rockwell, Mooney, Ercoupe, etc. driver >say they wished they had their fuel in the cockpit !!!!!!! > I think it was me that said a pilot at my field dis-liked his tanks. The biggest concern was that they caused wing heaviness with very little fuel level difference and the other thing was he felt they caused erratic roll control during banking and strange pitching moments when accelerating and decelerating. Although if he was making a coordinated turn the fuel should stay in the same place as level flight. He has two baffles installed in each tank. He also felt he could lighten his airplane by 40 pounds by going to the stock RR header tank. PS Cessnas, Pipers, and Ercoupes have header tanks I think. :o) Not sure about the others. zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz Micheal Mims SP290,.. Filling and sanding now! mailto:mikemims@pacbell.net http://www.geocities.com/CapeCanaveral/Hangar/4136/ Irvine Ca Fax 949.856.9417 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ ------------------------------ Date: Mon, 15 Jun 1998 19:19:41 -0700 From: Micheal Mims Subject: Re: KR: RV-8 Accident At 08:08 PM 6/15/98 +0000, you wrote: >also heard that the dan denny thunder mustang suffered a similar >inflight failure - pulled the wings off- anyone hear about this. steve > I just heard of that this weekend. I don't know any more than what you just stated though. Maybe we should try to keep these little airplanes under mach 1.5 huh? (mach one in the homebuilt world is 200mph, this according to Area 51 statutes of course) zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz Micheal Mims SP290,.. Filling and sanding now! mailto:mikemims@pacbell.net http://www.geocities.com/CapeCanaveral/Hangar/4136/ Irvine Ca Fax 949.856.9417 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ ------------------------------ Date: Mon, 15 Jun 1998 22:39:45 EDT From: Horn2004@aol.com Subject: KR: Re: Thunder Mustang Accident In a message dated 6/15/98 8:05:05 PM, you wrote: <> Dale Clark was the factory pilot for Thunder Mustang. He was taking a prospective customer for a demo ride. Dale was here in Dallas about a month ago and gave me a nice close look at the Mustang and gave our EAA chapter a 2-hour presentation on the Mustang. He was an incredible pilot who was very well known in the warbird community. Dan Denney hired him to help get the warbird community "behind" the Thunder Mustang. Dale had hundreds of hours in the Thunder Mustang and thousands of hours in warbirds/high performance aircraft. We received word from Dan Denney about a week ago that the Mustang crashed. It went in at a high rate of speed killing both pilot and passenger. The mustang hit at approximately a 50 degree nose down angle. The aircraft was completely destroyed. The engine was running at impact. There was no evidence of any in- flight structural failure upon preliminary investigation. We lost a very good man and probably one of the finest engineered homebuilt aircraft I have every seen. Steve Horn Dallas, TX horn2004@aol.com ------------------------------ Date: Mon, 15 Jun 1998 21:43:34 -0500 (CDT) From: Steven A Eberhart Subject: Re: KR: RV-8 Accident On Mon, 15 Jun 1998, Micheal Mims wrote: > At 08:08 PM 6/15/98 +0000, you wrote: > >also heard that the dan denny thunder mustang suffered a similar > >inflight failure - pulled the wings off- anyone hear about this. steve > > > Preliminary NTSB report for the RV-8 indicated that there was an inflight breakup with a wing departing the aircraft. Preliminary NTSB report for the Thunder Mustang is unconclusive at this time. Engine was making power, structure apeared to be intact. They recovered the engine computers and are going through the data. They have all the engine data on 1 second intervals from takeoff. > I just heard of that this weekend. I don't know any more than what you just > stated though. Maybe we should try to keep these little airplanes under mach > 1.5 huh? (mach one in the homebuilt world is 200mph, this according to Area > 51 statutes of course) Well put, I think there is a barrier, like a wall there. Heard that some where. Seriously I agree completely with the mach 1 being at 200 mph. Steve - ------------------------------------- http://www.newtech.com/nlf One test is worth a thousand expert opinions but a thousand opinions are easier to get. ------------------------------ Date: Mon, 15 Jun 1998 22:52:33 EDT From: Kr2dream@aol.com Subject: Re: KR: wing tanks Ercoupes have three tanks and only ONE of them is vented. The fuel pump pumps from a tee between the wing tanks to the header tank which has an overflow to the left wing tank which is cross-connected to the right wing tank. The header is the last to drain. I have had a number of people refer to it as one of the best fuel systems flying. I have a copy of the Ercoupe drawings if anyone is interested. Bob Lasecki Chicago and still trying to build. ------------------------------ Date: Mon, 15 Jun 1998 23:30:03 -0400 From: Tom Andersen Subject: Re: KR: wing tanks Larry, If I understand you correctly, you have tanks about eight feet long, ten inches wide and 4.5 inches deep? Wouldn't this place the center of weight of the fuel tanks rather far out on the wing, like about six or seven feet out? I can readily see all kinds of weird flight characteristics with the tanks half full. If you were to slip for an extended period on a cross-wind landing approach, couldn't all the fuel run to the wingtip of one wing and the root of the other, causing a wing-heavy condition even if they both contain the same amount of fuel? - -Tom Flesner wrote: > At 01:24 PM 6~14~98 -0400, you wrote: > >Larry, > >What is the capacity of your wing tanks? Are they in your stub wings or > in your > >outer wing panels? > >-Tom > > > Tom, > > I placed my wing tanks in the outboard panels. I built the stock length > wing and the tanks are from the forward spar rear face and ten inches > toward the trail edge.(roughly 4.5x10xwing length) They run from root > to tip and have three 2 inch foam baffels with only a one and one half inch > semi-circle opening for fuel to flow between compartments. There is a > 1/4 inch vent from one bay to the next at the highest point to prevent > air locks. The slosh > holes are on the very bottom. I didn't want the fuel to flow from root > to tip and back too quickly and get weight shifting. I installed the vent > at the forward tip end just outside the fill ports. There is a drain at the > inboard trailedge of the tank and the pickup is recessed in the bottom > center at the root. Math tells me I have twelve and one half gallon in > each wing. I use one flex hose at the attach point with metal fittings and > the rest of the line is all 3/8 inch alum. I use two facet pumps in > parrallel. > The line from each tank comes in to a shutoff valve just before the pumps. > I can pump from either tank or both with either pump or both and with both > valves "on" the system will crossflow. I can shut one tank off if I want to > manage wing weight just like I have to do in the TriPacer that has no > "both" selection in the fuel system. > > Yes , my KR is heavy but it was not the fuel system that > caused the problem. I could eleminate maybe 15 pounds by removing > the second battery system, one fuel pump, one valve, and associated > fuel line. With any kind of wing tanks you will need a fuel pump of some > kind and my two wing tanks are maybe 30% heavier (W.A.G) then a > 16 or 18 gallon header tank. I felt I needed more tankage than that with > an 0-200. > > For those building header tanks, make sure you clamp down the line > somewhere before the firewall and then install a pull-apart between > there and the firewall. One KR accident report related a KR making > a hard landing that caused the firewall to separate from the fuselage. > the fuel line pulled the bottom of the tank out and covered the pilot > with fuel. How LUCKY he was that it never ignited. > > For Jeff, what was it the pilot at your field disliked about wing tanks? > If there is something I should know , please tell me. I've never heard > a Cessna, Piper, Bonanza, Rockwell, Mooney, Ercoupe, etc. driver > say they wished they had their fuel in the cockpit !!!!!!! > > Larry Flesner > > P.S. you fellows with wing tanks and only one pump might want to do > a weight and balance with fuel only in the wings and the header > near empty. Steve Altman (sp) from Colorado had his pump quit on the > way to Rrough River and said he was getting pretty tail heavy by > the time > he landed. You may want to land and transfer fuel if that happens. > One more thing to think about !!!! ------------------------------ End of krnet-l-digest V2 #96 ****************************