retractable gear on RVs?

[diamond]

Sorry if this is dumb, but I'm at the bottom of the learning curve. With all the mods I read about for RVs, is there a mod for retractable landing gear, especially for the taildragger -7 or -9? If so, other than looking cool in the air, what is the upside and downside of doing this? Thanks

[Kahuna]

Recommend you use the search function.
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Search, advanced, retract, search titles only, Wallah

You can do the same for retractable, or other terms of interest.
Start with titles only, move on to posts if you dont like what you get.
You will find much material.

[Steve A]

Several years ago Kitplanes (or EAA Sport Aviation mag) had a feature on a guy in Germany adding retractable gear to an RV. He had both a retractable and fixed and after a ton of work, the retractable gear added about 2-3 knots to the total speed. The article was interesting to read and the technical obstacles overcome were formitable, but bottom line is the fixed gear is very efficient with the proper fairings.

S S Anderson
RV 7A Flying
Await kid graduation to buy more avgas

[David-aviator]

Originally Posted by Steve A

Several years ago Kitplanes (or EAA Sport Aviation mag) had a feature on a guy in Germany adding retractable gear to an RV. He had both a retractable and fixed and after a ton of work, the retractable gear added about 2-3 knots to the total speed. The article was interesting to read and the technical obstacles overcome were formitable, but bottom line is the fixed gear is very efficient with the proper fairings.

S S Anderson
RV 7A Flying
Await kid graduation to buy more avgas

Burt Rutan determined the same thing many years ago with his canard airplanes. It simply is not worth the complexity and cost to do it. If we flew at 400 knots it would be another matter entirely, but not at the speeds we fly.

The cost of maintaining the retraction system is much over the years. Every annual the certified retracts have to be swung plus insurance premiums are always higher as there is some truth to the saying there are those who have and those who will - land gear up.

The only thing that prevents it in big airplanes is a checklist, another crew member reading it, and the death penalty if you don't.

[Shockwave]

Upside is 2-3kts, less fiberglass work which some seem to hate with a passion, and easier tire inspections. Short of a major new finding in cooling drag, this may be one of the last places to pick up knots after the aft cowling fairing.

Downside is designing and engineering your own solution, as there aren't any ready-made mods that I'm aware of. You might be able to kit-bash from another plane, but you'll still have to incorporate that design in and really test it out.

I would think it'd be easier than the stretch 6. If you want it bad enough, it's not insurmountable. It would be a big undertaking however.

[schimms]

Pics taken on the 2nd RV meeting in Damme, Germany. I hope the owner doesn`t mind me posting these.

[pierre smith]

Very well done example but I'm guessing an additional 250 lbs or more. I also read that this airplane cruises right at VNE, not just 2-3 knots faster.

Regards,

[airguy]

Originally Posted by pierre smith

Very well done example but I'm guessing an additional 250 lbs or more. I also read that this airplane cruises right at VNE, not just 2-3 knots faster.

Regards,

Possibly - but that's a function of power as well - and with that 3-blade prop the obvious question is what engine is installed?

[Mel]

Originally Posted by Shockwave

Downside is designing and engineering your own solution, as there aren't any ready-made mods that I'm aware of. You might be able to kit-bash from another plane, but you'll still have to incorporate that design in and really test it out.

Another downside not mentioned is the placement of the fuel tanks farther outboard.

[DanH]

That 'ole boy has been tinkering with a lot of things...for example, check out the cooling air exit area and exhaust system.