Here's my experience: My engine will crap out (hickup) as I get close to zero 'g' (I think it's because of my carb/float bowl). I can do almost all acro without any zero or negative 'g'. My rolls are barrel rolls, not aileron rolls. I've often had a brief hickup doing them, though a barrel roll can be done without really low 'g' force. The roll on a point during cuban-eights is so fast that I haven't experienced a hickup. I've always though the lazy-eight is a great maneuver with the Lancair, and I've never experienced any hickup doing them.

I doubt that the hickup could cause any harm to the engine, but low oil pressure sure could -- avoid it. I would vote for COMPLETELY avoiding zero and negative 'g'. Most of the maneuvers can be done without going to less than 1/2 'g'.

Add slow flight maneuvering to your regimen. It's a great way to stall proof yourself and make your coordinated control inputs nearly instinctive.

Most of the non-normal flight maneuvers I do are limited to lazy-eights (they're a thing of beauty), chaundels (sp), and extreme slow-flight. They all have a very direct pay-off in developing a real feel for the airplane at very low risk.

Statistics suggest that there are significant risks involved for you doing this stuff. Make sure it pays off.

> To:
> Date: Sun, 6 Dec 2009 12:32:22 -0500
> From: keith.smith@gmail.com
> Subject: [LML] basic aerobatics in a 360
>
> I'm thinking of doing some relatively basic aerobatics in my 360,
> basically loops, barrel rolls, and anything else with continuous
> positive G.
>
> The area where I'm a little hazy is any maneuver with brief moments of
> zero or even -1G. Are these to be COMPLETELY avoided, or is it ok for
> very brief stints. I'm concerned about the prop and engine. My
> knowledge of the internals of the engine are weak, but from the little
> I know, without an inverted oil system, prolonged inverted flight
> isn't an option. My question is, is 0 to -1G acceptable for 1-2
> seconds? I'm thinking here of aileron rolls, or cuban eights.
>
> I don't have my heart set on doing those, per se, but just want to
> know where it would be smart to draw the line. I know the airframe can
> handle all of that, and then some, it's a question of the engine and
> prop.
>
> Thanks for any advice.
>
> Keith
> N360JH LNC2
>
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