An SNJ doesn't "corkscrew" very much. It would hardly be
enough to provide positive G in excess of 1.0.
Well, the *whole point* of a textbook aileron roll is to maintain
positive G's -- not 1+ G's, but *positive* -- all the way through the
maneuver....
Sorry, I didn't express myself well. I meant "It would hardly be
enough to provide positive G in excess of 1.0, enough to negate the
negative 1 G caused by gravity, plus a bit more to make it a positive
G maneuver."
BTW, I looked again at a tape of Tex Johnston's rolls, going and
coming. I cannot detect any "corkscrewing."
regardless of whether you do it in a Pitts or a puny Aerobat
(the Pitts is a lot more, erm, exciting in this respect :-)).
I'm sure it is. I've had a little time in a friend's Starduster 2
but never had the pleasure of flying a Pitts.
It does start with a slight pullup, but then then back-prssure on the
stick is released, to produce what approximates a zero-G situation.
(Don't you do that in an Aerobat?)
The textbook aileron roll in an Aerobat starts with a shallow dive to
120 KIAS, then a smart pullup to 30 degrees pitch, then a quick
simultaneous full-over on the ailerons and neutralization of the
elevator until pullout. Apply rudder as appropriate...
I would agree with that, except I neutralize the elevator THEN begin
the roll.
I don't think of the pullup as part of the maneurver, but as
"preparation" for it.
In fact, it's close to 2G's at two points in
the maneuver (pullup and pullout), and it's probably around .5 to 1 G
over the top.
I don't think of the pullup as part of the maneurver, but as
"preparation" for it. I don't pull up that sharply, and if I have to
"pull out" at the end, I figure I didn't do it right.
If by "over the top" you mean when 180 degrees inverted, I find that
very hard to imagine, based solely on my experience. (I've never
flown an airplane with a G-meter.) I don't hang on the seat belt, as
in a slow roll, but I feel a bit "weightless." I don't seem to be
pushing down (up?) on the seat very hard.
Remember, half way around your altitude is still quite a bit higher than
it was when you started the maneuver....
Yes, I think the airplane follows something like a "ballistic curve"
during the maeuver. Certainly, it gets dang little vertical lift as
it rolls past the 90 degree and 270 degree points.
Despite the fact that the nose is pointed up slightly, the airplane is
essentially "falling" and thus it, and whatever is in it, is
experiencing zero Gs. (One G from gravity, counteracted by one G from
the accelleration.)
vince norris
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