Rolling a 172 - or not

Robert

You talk about doing a LOOP in association with a roll. A LOOP has no
roll in it.The ailerons are only used to keep the wings 90 degrees to
the plane of the loop. A IMMELMAN or CUBAN EIGHT has a roll
associated with part of a loop.

The description of making a corkscrew inside a tube is another way of
defining the flight of the airplane when it does a BARREL ROLL.

In my prior post I said to pull one 'G' when I should have said two
'G'. Same 'G' as pulled in a one 'G' turn (one gravity 'G' and one
acceleration 'G').

Not sure you would or would not call a barrel roll a compition
maneuver. Never flew in compiton. In the airshows we used to put on
didn't do BARREL ROLLS becaue they were not very spectular from the
ground nor percicsion manuevers..

In airshows many times we would do a 8 point SLOW ROLL stoppmg
momentarily every 45 degrees of roll. This is a precison maneuver and
takes a lot of practice with elevator, rudder and aileron in
coordination to do correctly and with precision so looks good from
ground. Seen in compition today.

My reference is years and years of doing acrobatics and teaching same
in both conventional aircraft and jets.

As a matter of interest, most of the victory rolls you see of Fighters
returning from a combat mission with kills are aileron rolls. You
could see some (rare) put a little forward stick in when inverted but
had to look close.

Some birds didn't do good aileron rolls (P-51 for instanace) If you
did an aileron roll on the deck you normally bumped the stick upside
down to keep the nose up. The P-40 however aileron rolled like a spool
on a thread.

Big John


On Sun, 09 Nov 2003 03:55:51 GMT, Robert Moore
wrote:

Big John wrote
1. A 'barrel roll' is a roll where (if done properly) you as a
passenger, with your eyes closed, can not tell you did a roll.
The ball stays centered and if one 'G' is maintained, it feels
like straight and level flight. Starting nose position and of
course air speed varies between underpoweed GA aircraft and
super sonic Fghters.

Hey John, I didn't make-up that post, it came straight 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.

Care to give us a reference for your definition?

Bob

Big John wrote

You talk about doing a LOOP in association with a roll.

No John, I didn't talk or write about...... I just quoted from the
acro.harvard.edu web site and William Kershner's fine book.
You may not have seen the picture from the Kershner book when you
wrote this, but write back when you have seen the barrel roll as
described by someone who is considered an authority in the field.

My reference is years and years of doing acrobatics and teaching
same in both conventional aircraft and jets.

Still waiting for reference documentation. :-)

Bob

In article ,
Robert Moore wrote:


No John, I didn't talk or write about...... I just quoted from the
acro.harvard.edu web site and William Kershner's fine book.
You may not have seen the picture from the Kershner book when you
wrote this, but write back when you have seen the barrel roll as
described by someone who is considered an authority in the field.

I've been shown two different ways to do a barrel roll.

The first was to pick a reference off one wingtip. Start pulling and
rolling toward the reference point. Once inverted you would be 90
degrees off original heading (pointed at the ref point). You continue
to roll and pull returning to the original heading.

The second way was to pick a reference point over the nose. Put the
nose slightly to one side of that point then roll and pull keeping the
nose the same distance from the reference point.

The first is the big loopy typy barrel roll - and a lot of fun to do.

The second is a much tighter roll without any loop.

--
Dale L. Falk

There is nothing - absolutely nothing - half so much worth doing
as simply messing around with airplanes.

http://home.gci.net/~sncdfalk/flying.html

Dale wrote

The second way was to pick a reference point over the nose. Put
the nose slightly to one side of that point then roll and pull
keeping the nose the same distance from the reference point.

This is what Kershner has to say about the second method.

"Another method of doing a barrel roll is to pick a reference on the
horizon, turn the airplane 45° to the reference point, and proceed to
make a wide roll around this real point. One disadvantage of this
method for the newcomer is that it depends on the pilot's own
judgment of how large the orbit around the point should be. For an
introduction to the maneuver, the first method is usually better, but
you may prefer the second and work out your own techniques of
instructing it."

It should be noted that by using the 45 degree angle to the reference
point, one gets the same maneuver if done properly.

Bob Moore

Big John wrote

My reference is years and years of doing acrobatics and teaching
same in both conventional aircraft and jets.

Check-out Mr. William Kershner at:

http://www.kershnerflightmanuals.com/

Bob

Bob

Read Kershner's life story. Note that he left Moffett and crapped out
of the Navy the year I arrived at Moffett to fly All Weather Jet
Fighters (VF-23).

The Navy was just transitioning from Prop Fighters (F4U like he flew
in West Pac, etc) and one of my tasks was to give them the experience
of Air Force Jet Fighter operations including energy management which
was very important in those first generation jet fighters..

Reading his description of life events it seems he pushes the envelope
some like Zzzzom.

I see nothing he has done to warrant your placing so high on a
pedestal. He gives credit to only one document where he lifted some
data/technique. I also detect the wording of other manuals I have seen
through the years that he didn't give credit to.

Of course it may be just how many ways you can say loop?

He says he flies one or two students a month.That's not enough to
maintain proficiency or write from a current background.

You keep asking for my credentials. What do you want, my Military Form
5 where every flight I make in 28+ years is listed. There is at least
one or more pages per month depending on activity and totals well over
350 pages and about 2 1/2 - 3 inches thick weighing 3-4 pounds.

Or my formal education of BS with work on a MS.

Or the Patent number of my patents?

I'm married and have four grown daughters with three grand children
and three great grand children.

I'm over 21 and legal to buy 'booze' so drink Vodka on the rocks.

My GA Flight Logs are pretty thin as I didn't log a lot of the time
because I wasn't trying to build to any number of hours since I had
over 6500 in heavy iron.

It looks like there are several different ideas about acrobatic flyng
on this thread. I've expounded on mine so others can list their way
and I'll set back and might learn somethng??? One is never too old to
learn it is said.

I don't suffer fools but can be moved by facts.

Fly safe and keep the ball in the center unless you are slipping the
excess altitude off on final or landing in a cross wind.


Big John



On Sun, 09 Nov 2003 23:12:40 GMT, Robert Moore
wrote:

Big John wrote

My reference is years and years of doing acrobatics and teaching
same in both conventional aircraft and jets.

Check-out Mr. William Kershner at:

http://www.kershnerflightmanuals.com/

Bob

Big John wrote:

Robert

You talk about doing a LOOP in association with a roll. A LOOP has no
roll in it.The ailerons are only used to keep the wings 90 degrees to
the plane of the loop. A IMMELMAN or CUBAN EIGHT has a roll
associated with part of a loop.

The description of making a corkscrew inside a tube is another way of
defining the flight of the airplane when it does a BARREL ROLL.

As a lurker here who has never and will never do a single loop or roll, it
seems to me you two are both describing exactly the same maneuver but using
slightly different words.

Both you and Bob agree that the barrel roll consists of having the airplane
follow a corkscrew path as if it were following the inside wall of an
imaginary barrel, or tube, in the sky.
If the plane were to roll while going straight down the long axis of the
tube it would be an ordinary "slow" roll. OTOH, if the plane were flying
along the inside circumference (i.e. at 90 degrees to the long axis) of the
tube it would be doing loops. The corkscrew path of a barrel roll is
halfway between these two situations (i.e. at about a 45 degree angle to
the long axis of the tube), so it doesn't seem unreasonable to describe it
as the combination of a loop and a roll.