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"Andrew Boyd" wrote in message
m...
wrote:

So if I normally commence a loop at 100 knotts but get the
entry speed wrong and start at 105 knots ....

Anyone care to formulate what happens when speed ( or "G")
are not constant?

Your speed and G are NEVER constant during a loop. A
vertical maneuver is always low and fast, then high and slow,
then low and fast again, etc.

You continually convert your kinetic energy at the bottom,
to potential energy at the top, then back to kinetic energy
on the downline. A hhead (aka stall turn) is a perfect example
of this. You go straight up until you stop, then pivot, and
fly down and gain airspeed again.

Given a constant density altitude, additional entry speed
implies additional G to make the same radius, assuming you
fly at (or near) the stalling AOA which generates Clmax.

Think of it this way: given that you fly at Clmax:

1) the radius of the vertical maneuver is a function of the
aircraft stall speed (Vs), and

2) The G you must pull or push is a function of the entry speed.

Does that make sense? It's not completely true - it will not
withstand a rigorous proof, but practically speaking, it's
what you really need to know to yank and bank down low.

Thanks for the informative posts. I wish we had more discussion on this
newsgroup about the physics of aerobatic flight. Here is an interesting
article in Air Force Flying Safety regarding optimizing the pullout in an
altitude-critical situation. I found it very interesting reading and
perhaps relevant to this discussion.
http://afsafety.af.mil/magazine/htdo...98/pullout.htm

Cheers!

-justin
yak52 driver