"Bertie the Bunyip" wrote in message
. 130...
"Maxwell" wrote in
:


"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. You would continue this maneuver, gradually flattening the spiral as
gravity takes over the acceleration into the seat until you are again
straight and level. You would never "climb" against gravity at any point
since that would create an acceleration above 1g. Of course I guess this
isn't technically a barrel roll but my question refers to the possibility of
keeping a constant 1g as felt in the seat throughout the maneuver. Like this
crappy drawing as seen from behind:
http://home1.gte.net/res0f19c/dir1/spiral.jpg

TP