Mild Aerobatics

Jay Honeck wrote:

However, I did (and still) wonder about putting that much negative-G on our
34 year old airframe. Without a G meter it's impossible to know how much G
was induced, but I'd say it was 50% more than I've ever done before. (The
only negative G maneuver I ever do is the push-over at the top of a steep
pull-up, known by my kids as an "Up-Down".) Was 50% more too much?

Jay,

As others have pointed out, you alomst certainly didn't hit much
negative g or you'd really know it. A full negative 1 g would result
in you hitting the straps firmly, loose objects flying all around
inside of the airplane, and a dust storm you can't imagine from the
carpet in a 'clean' airplane (trust me on that one). Negative 2 takes
work. Negative 3 *hurts*.

Think about it this way: when you unloaded the wing the airplane's
primary structure was actually under less stress than it had been while
cruising along straight-n-level... it was no longer carrying any
weight! I don't know what the loads on the tail are when you push
over, but I'm betting that they're not that much, either.

No fears.... Atlas remains trustworthy.

-Dave Russell
N2S-3

In article 7kLKe.239817$x96.9166@attbi_s72,
"Jay Honeck" wrote:


However, I did (and still) wonder about putting that much negative-G on our
34 year old airframe. Without a G meter it's impossible to know how much G
was induced, but I'd say it was 50% more than I've ever done before. (The
only negative G maneuver I ever do is the push-over at the top of a steep
pull-up, known by my kids as an "Up-Down".) Was 50% more too much?



I doubt you had the negative G's you thought you had...

Trained military pilots start 'redding out' at negative 2 to 2.5 Gs and
anything more than negative 1.5 is quite uncomfortable

--
Chris Schmelzer, MD
Capt, 110th Fighter Michigan ANG
University of Michigan Hospitals
Ann Arbor, MI

On Thu, 11 Aug 2005 16:49:07 GMT, "Jay Honeck"
wrote:

As another reference point (and a crude way of measuring the negative Gs), I
routinely read about guys doing the "up-down" maneuver to the point where
their engine sputters due to fuel starvation.

I've done that with Cherokees since the 1960s. It doesn't hurt them
at all. And it is a wonderful way to teach the kids about physics.
It's called a parabolic arc and it's not an aerobatic maneuver.

Since that flight I've carefully
inspected the empennage, and there is obviously no visible stress or strain,
or I wouldn't be flying it -- but how can you really know without extensive
metallurgic testing?

Think about it Jay. When you're just flying along, there is a large
load on the the stabilator forcing the tail down to make the plane
stable (hence the term). When you "unload" the stabilator you've
given it a nice little rest.

I knew a pilot with a Commanche that put 50 pounds of lead in the tail
cone. It made it go faster. Really not that much faster, but the
plane flew better. That was also a long time ago! And I loved flying
that Commanche.


If you've ever looked at the stabilator attachment on a Cherokee you will
marvel at the simplicity and apparent fragility of the design, so inducing
excessive negative-G is something we never, ever do.

Don't ever look closely at a helicopter.

Mike Weller

"Mike Weller" wrote in message
I knew a pilot with a Commanche that put 50 pounds of lead in the tail
cone. It made it go faster. Really not that much faster, but the
plane flew better. That was also a long time ago! And I loved flying
that Commanche.

How about spinning it?

moo

On Sat, 13 Aug 2005 14:46:13 -0400, "Happy Dog"
wrote:

"Mike Weller" wrote in message
I knew a pilot with a Commanche that put 50 pounds of lead in the tail
cone. It made it go faster. Really not that much faster, but the
plane flew better. That was also a long time ago! And I loved flying
that Commanche.

How about spinning it?

moo


Not a good idea. Even Cherokees take a lot of altitude to recover
from a spin.

Mike Weller

If you've ever looked at the stabilator attachment on a Cherokee you will
marvel at the simplicity and apparent fragility of the design, so inducing
excessive negative-G is something we never, ever do.

Don't ever look closely at a helicopter.

And for you die-hard Cessna fans, don't EVER look at the wing spar attach
points... You'll never do a steep turn in your 172/182 again!

;-)
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"

Jay Honeck wrote:

If you've ever looked at the stabilator attachment on a Cherokee you will
marvel at the simplicity and apparent fragility of the design, so inducing
excessive negative-G is something we never, ever do.

Don't ever look closely at a helicopter.


And for you die-hard Cessna fans, don't EVER look at the wing spar attach
points... You'll never do a steep turn in your 172/182 again!

I have. What is the problem? :-)

Matt

And, as a wise old pilot once observed, the flight envelope is altitude
going up and airspeed going right. We mostly push the upper right corner of
the envelope. And that is also where the stamp gets cancelled.

Jim



". You have
a POH that offers you figures to follow that define your flight envelope,
then you have the reality involved with an aging airplane.

"RST Engineering" wrote

And that is also where the stamp gets cancelled.

Groan!
--
Jim in NC

Well it wasn't for fun, but while flying with my old instructor a
couple years ago on a night x-country he suddenly grabbed the controls
from me, rolled into a 45 degree bank, and pushed the nose down HARD to
avoid what appeared to be an imminent head-on mid-air. Definitely took
a flight within the plane for a couple of seconds during that maneuver,
but we cleared the traffic with no problem. (It probably wasn't all
that close actually, but when you see red on right, a white light, and
no movement, you get the hell outta the way).

--
Guy Elden Jr.