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Old June 12th 07, 07:05 PM posted to rec.aviation.piloting
Bertie the Bunyip[_2_]
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Default Myth: 1 G barrel rolls are impossible.

"muff528" wrote in news:V2Abi.5094$3Q4.153
@trnddc05:


"Bertie the Bunyip" wrote in message
.130...
"muff528" wrote in
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"Bertie the Bunyip" wrote in message
. 130...
"Maxwell" wrote in
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"Bob Moore" wrote in message
46.128...
My name is Bob Moore :-)

Just what is a barrel roll has been debated between "Big John",
Dudley, and myself at least twice in the past. It IS difficult to
describe without having a model airplane in one's hand and flying
it through the maneuver.

How come you don't seem to belive the following from Wikipedia?

Barrel roll
From Wikipedia, the free encyclopedia

This article is about the aerial sport. For the military

operation,
see Operation Barrel Roll.
A barrel roll occurs when an object (usually an airplane or

roller
coaster)
makes a complete rotation on its longitudinal axis while

following
a helical path, approximately maintaining its original direction.
The G load is kept positive (but not constant) on the aircraft
throughout the maneuver, commonly not more than 2-3 G.

In aviation, the maneuver includes a constant variation of

attitude
in all three axes, and at the midpoint (top) of the roll, the
aircraft is flying inverted, with the nose pointing at a 90-

degree
angle ("sideways") to the general path of flight. The term

"barrel
roll" is frequently used, incorrectly, to refer to any roll by an
airplane (see aileron roll), or to a helical roll in which the

nose
remains pointed generally along the flight
path. In fact, the barrel roll is a specific and difficult
maneuver; a combination of a roll and a loop. It is not used in
aerobatic competition.

From:
http://acro.harvard.edu

The Barrel Roll is a not competition maneuver. The barrel roll

is
a combination between
a loop and a roll. You complete one loop while completing one

roll
at the same time.
The flight path during a barrel roll has the shape of a

horizontal
cork screw. Imagine a big
barrel, with the airplanes wheels rolling along the inside of the
barrel in
a cork screw path.
During a barrel roll, the pilot experiences always positive G's.
The maximum is about 2.5 to
3 G, the minimum about 0.5 G.


Then would you label the roll that Jim has described here as a

form
of aileron roll, instead of a barrel roll? Or do you think it is
possible to do a 1g aileron roll?

It's less of a roll than it is a loop.


In fact, that's how I used to teach it. Get a hula hoop, cut it and
pull the ends apart. you are now looking at the path of a barrel
roll. A skewed loop


Bertie

Would it be possible to maintain 1g in the seat if the "corkscrew"
were modified to a shape like an opening spiral, similar to a

nautilus
shell? Maybe slip to the right while pulling the nose up to induce
acceleration of 1g.


No.

Bertie


Damn!


Stil, be a fairly interesting thing to try. You'd need a pretty powerful
airplane. Maybe you could get to name it.


Bertie