Conversion from RV-9 to RV-9A

Holger · #1 10-08-2010, 02:59 AM

Hi There,

I'm german and running a aircraft workshop in South Africa and holding FAA A&P/IA as well.
I got a phone call from a customer which has, after a ground loop, decided to convert his N- Reg tailtragger RV9 to a nose wheel RV9A.
This has been done not by himslefe but a local South African aircraft maintenace facility.
Now he asking me about the legal issues to sign off the conversion.

I'm not to much glued up with the experimental section in the FAR's. please can someone help me out there?
What are the legal requirements of signing off such modifications?
What are the changes in the structure - appearnatly the MLG leg attachments are moving from the engine mount backwards?
Are the parts for doing that coming in like a conversion kit?
If any what are the leagl documantations coming along with it?

Thanks a lot

Regards
Holger
Mercy Air SA

pierre smith · #2 10-08-2010, 05:44 AM

Is the airplane in the U.S. or South Africa? Maybe headed back to the U.S.?

You order the needed parts...I don't think that Van has "conversion" kit. Yes, the MLG mounts bolt to the center section and you need a new motor mount and a nose wheel leg...probably new main gear legs as well. The brake lines have to be re-routed, obviously and in the end, a new weight and balance calculated.

Mel or Vic (DAR's) , Designated Airworthiness Reps, can give you more details,

Best,

N941WR · #3 10-08-2010, 06:39 AM

Holger,

Welcome to the VAF forums.

Mel about covered the parts needed and the convers from TW to NW and the change might be easy or maybe not...

The tail wheel spring AKA stinger is held in with one bolt and is easy to remove. The question to ask Van's is, how will leaving the tail spring weldment in place, that far aft, impact the new W&B?

Remember, the new main landing gear will also be aft of CG, along with their weldments and additional bolts.

If Van's suggest you remove the tailwheel weldment, then you will have to drill out a bunch of rivets in the tail to get it out.

David-aviator · #4 10-08-2010, 07:05 AM

Holger,

Having done the conversion, here is what it entailed in the U.S.

Parts needed from Van's; a new engine mount, the main gear attach assembly left and right which bolts to the spar and fuselage just forward of the pilot seats, nose gear strut and wheel, main gear struts left and right. Same wheels and brakes can be used. The tail wheel assembly built into aft fuselage was left in place.

With regard to paper work; I wrote to the local FAA office and informed them that I wished to make the conversion and since the airplane is sold in either configeration, suggested no re-certification was required. They agreed. The work was signed off in the log by the builder (me) holding a repairman. The mod was considered major and the airplane went to phase one for testing and then returned to phase two.

DennisRhodes · #5 10-08-2010, 07:38 AM

I went the other way and removed a 9A gear arrangement and converted to 9. This was done however during the original building process and sign off was not an issue. I do howeverstill have all the Main gear Van fabricated assemblies and the 9A Main gear legs. And yes they are different and available if someone needs.