Rolling a Non Aerobat 150

john smith wrote:
.... snipped
the rate of descent is still going to be about 800 fpm with an indicated
airspeed of 45-50 mph. That's quite and airload on the inside turn side
.... snipped

800 fpm is surprisingly low - are you sure? The aircraft I normally fly
does about 300 feet per turn and about 1-2 seconds per turn - so being
conservative that's about 10,000 fpm.

Dave

I know of one to get out of a decathlon. It was from the back seat no less.
(It helps when the wing has departed and there is a big hole above your
head though)

Mike

john smith wrote:
In article . net,
"Todd W. Deckard" wrote:

Why would you say this? The door would be fairly easy to open in a spin.
In a high speed loss of control it might be very difficult to overcome
aerodynamic resistance but it is possible to open a forward hinged door
and force it open enough to squeeze out at even 100kts in straight flight.
With a modern canopy you stand a chance of a survivable deployment at
even a few hundred feet.

I wouldn't be too positive about those statements.
I have over 300 freefalls and 25 hours of acro in a Citabria.
The Citabria only has one door... on the right side. In a right spin,
the rate of descent is still going to be about 800 fpm with an indicated
airspeed of 45-50 mph. That's quite and airload on the inside turn side
of the airframe. Add to that centrifugal forces and getting through the
doorway after jettisoning the door will be a challenging proposition.
You have two sets of seatbelts to release, a headset to remove and a
body with a parachute attached to fit through the doorway. When you exit
you will be on the inside side of the airplane, which you have to clear
before you pull the D-ring.
Tic-toc, the clock is winding down as fast as the altimeter.
I have knowledge of only one acro pilot who successfully exited a
Decathlon.

On 2007-02-28 19:41:14 -0800, john smith said:

In article . net,
"Todd W. Deckard" wrote:

Why would you say this? The door would be fairly easy to open in a spin.
In a high speed loss of control it might be very difficult to overcome
aerodynamic resistance but it is possible to open a forward hinged door
and force it open enough to squeeze out at even 100kts in straight flight.
With a modern canopy you stand a chance of a survivable deployment at
even a few hundred feet.

I wouldn't be too positive about those statements.
I have over 300 freefalls and 25 hours of acro in a Citabria.
The Citabria only has one door... on the right side. In a right spin,
the rate of descent is still going to be about 800 fpm with an indicated
airspeed of 45-50 mph. That's quite and airload on the inside turn side
of the airframe. Add to that centrifugal forces and getting through the
doorway after jettisoning the door will be a challenging proposition.
You have two sets of seatbelts to release, a headset to remove and a
body with a parachute attached to fit through the doorway. When you exit
you will be on the inside side of the airplane, which you have to clear
before you pull the D-ring.
Tic-toc, the clock is winding down as fast as the altimeter.
I have knowledge of only one acro pilot who successfully exited a
Decathlon.

There was a guy down in Borrego Springs who managed to bail out when
his Citabria would not recover. Checking the wreckage later he found
the seatbelt from the rear seat had wrapped itself around the stick.

He could have sworn he had secured that thing.
--
Waddling Eagle
World Famous Flight Instructor

On Tue, 27 Feb 2007 21:35:00 -0500, "Capt. Geoffrey Thorpe" The Sea
Hawk at wow way d0t com wrote:

"RST Engineering" wrote in message
...
Note that what is said here is not true. The regs say that you can teach
any maneuver that is "required for a rating" without parachutes. This
includes spins. You can teach a student spins without a parachute(s) if
you wish.

Jim


And, one could consider the fact that wearing a parachute or not won't make
one bit of difference (at least as far as survival is concerned) in 90+% of
the aircraft used for training if one were to find a spin to be
unrecoverable and/or if one were to pull the wings off.

A spin is a fully stalled condition. The doors of a 150 or 172 should
be *relatively* easy to open as opposed to being in a high speed
spiral.


For the parachute to do any good, you would have to be able to open the door
far enough to actually get out of the airplane. You could do it in a
Citabria or 150 Acro with the door release - or something like a Cub. But
anything else? Naah...

But, of course, if one were to die inside the aircraft, having a 'chute on
should be enough to assure that one would go to heaven since he and/or she
would have died while complying with FAA regulations. The rest of us will
end up in a significantly less comforable environment, eh?

Personally I think spins are fun.
Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com

On Fri, 02 Mar 2007 01:38:09 -0500, Roger
wrote in :

A spin is a fully stalled condition.

I would characterize it as more of a condition where one wing is
partially stalled.

On Fri, 02 Mar 2007 20:40:18 GMT, Larry Dighera
wrote:

On Fri, 02 Mar 2007 01:38:09 -0500, Roger
wrote in :

A spin is a fully stalled condition.

I would characterize it as more of a condition where one wing is
partially stalled.

Or more stalled than the other. Either way a spin is a pretty benign
condition in most of the stuff we fly. OTOH an acellerated or inverted
spin is a bit more interesting.:-))

But the point is that in a regular spin the doors should be relatively
easy to open in a 150 or 172.

Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com

Roger wrote:



A spin is a fully stalled condition. The doors of a 150 or 172 should
be *relatively* easy to open as opposed to being in a high speed
spiral.

As I understand it, there is a difference in the _extent_ of the stall
between the two wings. If that were not the case and both wings were
fully stalled (which would require AOA to be ~90 degrees I think) the
yaw would decay due to fusilage and tail drag?

Cheers Mark

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On 2007-03-05, DR wrote:
Roger wrote:
A spin is a fully stalled condition. The doors of a 150 or 172 should
be *relatively* easy to open as opposed to being in a high speed
spiral.

As I understand it, there is a difference in the _extent_ of the stall
between the two wings.

I think 'fully stalled' in the context of a spin means that both wings
exceed the critical angle of attack. That's not to say one wing can't
have a different AoA than the other (IIRC, the critical angle of attack
is something on the order of 16 degrees)

--
Yes, the Reply-To email address is valid.
Oolite-Linux: an Elite tribute: http://oolite-linux.berlios.de

On Mar 4, 8:59 pm, DR wrote:
Roger wrote:

A spin is a fully stalled condition. The doors of a 150 or 172 should
be *relatively* easy to open as opposed to being in a high speed
spiral.

As I understand it, there is a difference in the _extent_ of the stall
between the two wings. If that were not the case and both wings were
fully stalled (which would require AOA to be ~90 degrees I think) the
yaw would decay due to fusilage and tail drag?

Cheers Mark
thought I'd jump in on this one. I've been a Stearman driver for about 30 years and might have about as much time in "unusual attitudes" as right side up. In a fully developed spin, the door on the outside of the spin will be pretty difficult to open, and in fact it's tough to even move yourself out on that side. the old military training in open cockpits was to bail to the inside of the spin if unrecoverable. so, the quick release pins are in the aerobat to ensure you can get the door off- Centrifigal force and wind presssure will keep it closed otherwise.

If you do manage to get out of a spinning aircraft, I wouls estimate close
to a 100% better chance of survival if you have a chute on. I sure would
hate to be the person who was able to get out of the so called "impossible
aircraft to get out of" only to find they didn't have a chute on.

Wear a chute, what can it hurt?

Adam

Adam Cope
www.dcaerobatics.com
703-623-9445