Retractable gear on an RV, for reliability and simplicity if a person was going to try and reverse engineer a system into the RV?s who?s has the best design to start with?
Thanks
Tim
Retractable gear on an RV, for reliability and simplicity if a person was going to try and reverse engineer a system into the RV?s who?s has the best design to start with?
first question is why do you want retractable gear? I can only think of three reasons: looks cool and different, it is a challenge and learning experience, and to go faster. For the first two, go for it. For the speed how much speed do you think you will get for all the trouble? Maybe 15-20 kts? What ever it is please see quote below.Retractable gear on an RV, for reliability and simplicity if a person was going to try and reverse engineer a system into the RV?s who?s has the best design to start with?
Since a clean RV can get near VNE in level flight with the larger engines would you not also have to consider flutter margins and possible changes to the tail?
George
FWIW, I have flown the retractable gear RV4 that has been pictured on these forums in the past. It was built by my friend David Lewis and his father some 23 years ago. The landing gear was adapted from the Celerity kit plane. The fuel tanks were moved outboard to make room for the gear. The engine is an angle valve 200hp. When the plane was completed and weighed, the tail wheel only weighed 12 POUNDS!!!! Can't remember the empty weight. For all the engineering and complexity the plane was only 7 MPH faster than a stock RV4 with a then non stock 180hp with a CS prop. I flew in formation with it all the way to Sun n Fun one time and have to admit that it looked really cool in flight.
I had the drawings and was going to build one, but the complete unstarted kit I bought had Phlogiston prebuilt spars and that ended that idea.
The airplane did slow down much faster than a stock RV4 though!
FWIW, I have flown the retractable gear RV4 that has been pictured on these forums in the past. It was built by my friend David Lewis and his father some 23 years ago. The landing gear was adapted from the Celerity kit plane. The fuel tanks were moved outboard to make room for the gear. The engine is an angle valve 200hp. When the plane was completed and weighed, the tail wheel only weighed 12 POUNDS!!!! Can't remember the empty weight. For all the engineering and complexity the plane was only 7 MPH faster than a stock RV4 with a then non stock 180hp with a CS prop. I flew in formation with it all the way to Sun n Fun one time and have to admit that it looked really cool in flight.
I had the drawings and was going to build one, but the complete unstarted kit I bought had Phlogiston prebuilt spars and that ended that idea.
The airplane did slow down much faster than a stock RV4 though!
Here's three reasons I can think of to go retractable:
1) You need to go over 300mph
2) You have a heavy airplane that requires large, complicated, shock absorbing struts and possibly big tires that have a lot of drag even if they have fairings.
3) You like spending time and money on maintenance and look for ways to do so.
None of these apply to an RV. Why put up with the horrendous complication and weight gain for, at best, 6-7 mph?
It would look cool though...
Tim
Tim,
Well said. However comma, Having shared a hangar and extensively flown both of the aircraft below I would add a #4.
4.) You like EZ's or KR retracts...(no electrics/hydraulics)
V/R
SmokeyQUOTE]
Could this possibly be #5? "You like to pay higher insurance costs"?
At least I've always read that insurance is quite a bit more costly with a retract vs. fixed gear...
It also has a tapered wing which he designed and built from scratch. Just flew a few months ago.
I took a few. None real good.If anyone has more photos of Marc's -7 from other angles, please post or contact me and i'll give you an email address to send them to. I'd love more info!
Sure looks cool i always wondered what preformance would be with skinny wing and retrack anyone got the #'s
Check out Danny King's latest modification
If I wanted an RV with retractable landing gear I would track down Bryan Carr in Langley, BC. He's currently working on what I think is his tenth RV or Rocket, and it will have retractable gear (it's an RV-4, IIRC). One of his earlier creations was an RV-4 with retractable gear.
Now I can finally keep up with the checkered-tail RVs.
I liked Danny's retracts so much I did the same to Smokey.
Now I can finally keep up with the checkered-tail RVs.
I mocked up a couple of paint schemes for the Pocket Rocket, but in the end the amount of metal flake paint was deemed to be too expensive. Here's what I had so far.Fuselage is based on an RV-4, but Bryan stretched it by a few inches (4?) and is using an O-375 from Aero Sport. He calls it a Rocket because that simplifies the paperwork. I'm pretty sure some pics will appear in a few weeks.
Not only has Bryan put in retractable mains, but his tail gear retracts as well. Better yet, it's taken him less than 4 years, start to finish on this aircraft which is ready for its first flight as soon as the paperwork arrives.
Fuselage is based on an RV-4, but Bryan stretched it by a few inches (4?) and is using an O-375 from Aero Sport. He calls it a Rocket because that simplifies the paperwork. I'm pretty sure some pics will appear in a few weeks.
The wrinkles are from the gear. I originally had the torque tube that it pivots on when retracting end there. I extended it to the rear spar to correct it. It tracks very good with the wide gear and is a blast to fly. I just got the gear doors on and will let you know how the performance is. I went on vacation before I got a chance to fly it. To learn more about it you can visit www.tropria.net/rv Marcus
If I wanted an RV with retractable landing gear I would track down Bryan Carr in Langley, BC. He's currently working on what I think is his tenth RV or Rocket, and it will have retractable gear (it's an RV-4, IIRC). One of his earlier creations was an RV-4 with retractable gear.
Not only has Bryan put in retractable mains, but his tail gear retracts as well. ... Fuselage is based on an RV-4, but Bryan stretched it by a few inches (4?) and is using an O-375 from Aero Sport. He calls it a Rocket because that simplifies the paperwork.
A fellow aviation photographer from my area recently posted the following picture on a discussion forum that we frequent. I wonder if it's the new airplane or the previous one.