Perfect loop

"Viperdoc" wrote in
:

I agree. Phil would have me pull just to the edge where the stick got
a little light, just before the airflow separated and got the usual
high AOA, high speed stall. Same with the pulls from the downlines-
bump the stick to load the G and then a hard pull just on the edge of
a stall (which sometimes happened). Nothing like doing a stall going
around 180k+ straight down with a hard pull! However, with some
practice I at least imagined I could feel the sweet spot just before
the burble of the stall.

When it was all said and done, the G meter would typically read max
6.7 to around -2.5, and I don't do snaps at more than around 120-130,
so I think most of the load came from the pulls to a vertical or other
looping figures.

Of course, my floor is 2,000, and early in the season I start a lot
higher, and certainly not on the deck. I've seen Patty fly many
times, at airshows, OSH, and in practice at St. Augustine, but I don't
ever recall a simple loop, but obviously quarter loops and pulls to a
45. I still can't imagine it would ever be as low as 4 G, and would be
somewhat surprised if less than 6-7, which seems to be the most
efficient G load to get the direction changed when going 160 (my
typical entry speed for a loop).

On the other hand, I've experienced some sustained 8G level turns in
the F-16 with full burner, and had the (not so enjoyable) experience
of 9G in a centrifuge. The sustained power was much tougher, since the
aerobatic planes bleed off energy so fast, as compared to a jet in
afterburner. The computer automatically limited the G load based upon
what we were carrying, which typically was two big drop tanks.

In the centrifuge the guy two rides before me had his heart slow down
and then stop. They did a crash halt, and with all of the running
around and sirens and flashing lights, he woke up and said he had been
having the most pleasant dream! The guy just before me completely
forgot about his G strain, and then puked before passing out.

My ride was next (what a smell), but luckily with my limited acro
experience I knew what to anticipate, and even then it was still hard.
Anyway, I would like to hear what Patty has to say.




Good God.
The stall is fairly easy to control in your Extra though, right? That is
to say you can keep it right there with a great deal of control at the
edge? I know the leading edge on those things is very blunt and rounded
and that should enable a large range of alpha and a fairly gradual
breakdown of laminar flow.


Bertie