Can Phil Lockwood’s Rotax RV 9 conversion be done on a tailwheel?

D

DMD3.

Pre-takeoff checklist
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DMD3.
Interestingly, N179RV was originally a tailwheel before the Rotax engine was installed. I’ve read some articles and watched the video, but Lockwood makes no mention whether or not the kit could be done on a tailwheel. Would the CG be different? Would the long nose make taxiing more difficult? If I see him at EAS this year, I intend to ask him.

Kelly Johnson's RV9 Pics

Here are some photos of the aircraft before the conversion.

(Posted this on Vansairforce but thought I’d paste it here too).
 
A: CG range is dictated by aerodynamics, not wheel locations.
B: The location of the main gear is determined by the CG and where you stick the third wheel.
C: It would be your kit and you can do anything you want to it.
D: Being able to see over the nose is overrated.
E: Long cowls and a lighter engine stuck further forward both have a detrimental effect on spin recovery.
 
I figured the lack of the nosewheel could potentially affect the CG by not having enough weight at the front. But in any case, someone on the Vans board said they asked and the fwf kit would work on both the nosewheel & taildragger version. Also, spin recovery is not much of a concern, as I don’t plan on doing anything to get myself in a spin.
 
Capt. Geoffrey Thorpe said:
A: CG range is dictated by aerodynamics, not wheel locations.
B: The location of the main gear is determined by the CG and where you stick the third wheel.
C: It would be your kit and you can do anything you want to it.
D: Being able to see over the nose is overrated.
E: Long cowls and a lighter engine stuck further forward both have a detrimental effect on spin recovery.
Click to expand...
Can you explain E? I would think this is not a huge effect in terms of rotational inertia but aerodynamics of the longer nose in a spin seem less intuitive.
 
Old97 said:
Can you explain E? I would think this is not a huge effect in terms of rotational inertia but aerodynamics of the longer nose in a spin seem less intuitive.
Click to expand...
Inertia changes may be more than you think. Moment of inertia varies linearly with mass but with the square of distance, so the same mass twice the distance from the CG will have a larger moment of inertia than twice the mass the original distance from the CG.

Aerodynamics certainly play a part, as the aero forces off the nose have a longer moment arm with the lighter/longer nose, and precession also plays a part in spin recovery if the prop is still spinning (also farther from the CG), but by and large the inertial changes are what usually get *my* attention in the first pass of analysis. Of course YMMV.

Nauga,
and the parallel axis theorem
 
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You'll be able to use an RV9a or RV9 with the kit.
 
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