Flat spins
A question or two for some of the aerobatic experts:
When I first did some aerobatics a few years ago, I was taught to use power during a spin to flatten the spin (in an appropriate type, of course). As power was added, the spin flattened out noticeably. We then removed power before recovering.
Since then, I've done a bit more spinning, here and there, in various different types including C150/C152. I love spinning, and haven't yet had any problems, but I do have (I hope) a healthy dose of caution every time I'm planning on spinning.
Yesterday, I found myself spinning a C152 Aerobat - one which I hadn't spun before. Other pilots who had spun this aircraft told me that it sometimes doesn't enter the spin very well, and a bit of power may help. I had a very good read of the relevant pages of the POH beforehand, and found something very similar in the POH. (Don't have it to hand, but it basically said that it may be necessary to use a small amount of power prior to the elevators reaching the full-aft position.)
I first tried a spin without any power, and found myself in something that looked more like a spiral dive than a spin. Recovered from that, climbed back up, and used a touch of power on the next try - and this time it spun just like I expected it to.
Ok, so the question: What exactly defines a "flat spin". How much power do you have to add before a spin becomes "flat"? Or is it just one of those gradual things, with no clear point at which a regular spin becomes flat? Would the spin which I did in the Aerobat count as flat? It didn't look very flat to me, despite having some power on.
And also, what would happen if I "forgot" to remove the power before trying to recover? This is something which I would ideally like to try (with someone who has more aerobatic experience than me!) rather than just read about. But during yesterday's spinning detail, the student I was flying with tried, several times, to recover without closing the throttle (despite me briefing him thoroughly beforehand on the correct technique - but we know how disorienting your first ever spinning session can be, so I don't blame him at all). I made sure I was quick to instruct him to close the throttle (and pushed his hand out of the way to close it myself once when he was a little slow)... but that was only because of my ignorance of what would happen if the throttle wasn't closed. Would it have been safe to allow him to recover with the throttle still slightly open? My thoughts were around possible engine or airframe overspeeding, but I would imagine it would also have an effect on the recovery itself?
Thanks!
FFF
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