aerobatic C172?

On May 2, 10:39 am, "Robert M. Gary" wrote:
On May 2, 7:18 am, C J Campbell
wrote:

The 172 may be able to stand the G forces, but that is not the only
limitation. The carburetor only works when right side up, for example.

Is that true? I can understand that the float would run out of gas
after a bit but I don't see how the carb itself would care about the
G's. In the Aeronca we were able to maintain inverted flight for more
than a couple of seconds before the engine would stop. The carb is
already on the bottom of the engine and the fuel/air mixture travels
up the intake via the massive suction of the intake stroke.

-Robert

Got to understand the carburetor. The gasoline is in a chamber,
its level kept constant by the float valve. The fuel leaves the
chamber by a small hole ("jet") in the bottom of that chamber,
travelling through the nozzle to be sprayed into the airflow. Turn the
carb over and the gasoline goes to the top of the chamber and the jet
gets nothing but fumes. The engine will quit. If the pilot is able to
maintain at least some fraction of positive G loading in the maneuver,
the fuel will stay in the bottom of the chamber and the engine will
run.

Dan

C J Campbell wrote:

The 172 may be able to stand the G forces, but that is not the only
limitation. The carburetor only works when right side up, for example.

If you maintain around one G throughout the manuever, the carb will
continue to work just fine.

As others have posted, it's not whether or not the plane can take the
forces generated in a properly executed manuever (which it can). It's more
whether the airplane can take the stresses of a botched manuever.

I've botched some manuevers in a fully aerobatic aircraft that would have
been pretty ugly in a non-aerobatic plane.

John Galban=====N4BQ (PA28-180)

--
Message posted via AviationKB.com
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Have you ever spin the Cherokee 180?

flynrider via AviationKB.com wrote:
C J Campbell wrote:
The 172 may be able to stand the G forces, but that is not the only
limitation. The carburetor only works when right side up, for example.

If you maintain around one G throughout the manuever, the carb will
continue to work just fine.

As others have posted, it's not whether or not the plane can take the
forces generated in a properly executed manuever (which it can). It's more
whether the airplane can take the stresses of a botched manuever.

I've botched some manuevers in a fully aerobatic aircraft that would have
been pretty ugly in a non-aerobatic plane.

John Galban=====N4BQ (PA28-180)

nobody wrote:
Have you ever spin the Cherokee 180?


Yes. I spin my Cherokee on a fairly regular basis. It takes a bit of
planning ahead to make sure it's in the Utility Category envelope, but it's
worth it.

John Galban=====N4BQ (PA28-180)

--
Message posted via AviationKB.com
http://www.aviationkb.com/Uwe/Forums...ation/200705/1

On 2007-05-02 14:47:53 -0700, "flynrider via AviationKB.com" u32749@uwe said:

C J Campbell wrote:

The 172 may be able to stand the G forces, but that is not the only
limitation. The carburetor only works when right side up, for example.

If you maintain around one G throughout the manuever, the carb will
continue to work just fine.

Yeah. I assumed that others had read the rest of the thread.




--
Waddling Eagle
World Famous Flight Instructor

On May 2, 7:18 am, C J Campbell
wrote:
On 2007-05-01 21:52:46 -0700, gt said:

I own a 1960 Cessna 172 with 2500 hours on the airframe. It is not
rated for aerobatic flight, but the positive and negative G loads that
it is approved for far exceed the normal G forces associated with a
well-executed barrel roll.

Has anyone heard of this maneuver being performed in a 1960 172?

Of course. However, that does not mean it is legal or smart.

The 172 may be able to stand the G forces, but that is not the only
limitation. The carburetor only works when right side up, for example.
A barrel roll should not be a problem, executed properly, but if you
screw it up then you might have some trouble. The 172 is allowed to do
spins, but it can be hard on the instruments, knocking them back and
forth from stop to stop. For that reason some FBOs insist that spin
training be done in other airplanes.

I suspect, however, that the real reasons the 172 is not certified for
aerobatics is Cessna didn't want the liability, the 172 has a
not-very-much-fun roll rate, and sooner or later some pilot would be
bound to do them with passengers and no parachutes.

Finally, if you are the sort of person who goes out and abuses other
people's property and tries to conceal it, I suspect that most of us
would not want you renting our planes.
--
Waddling Eagle
World Famous Flight Instructor


As I wrote, I own the plane. I do not and have not gone out and
abused other people's property. If I did, I wouldn't try to conceal
it, but thanks for the response.

On 2007-05-02 19:49:12 -0700, gt said:

On May 2, 7:18 am, C J Campbell
wrote:
On 2007-05-01 21:52:46 -0700, gt said:

I own a 1960 Cessna 172 with 2500 hours on the airframe. It is not
rated for aerobatic flight, but the positive and negative G loads that
it is approved for far exceed the normal G forces associated with a
well-executed barrel roll.

Has anyone heard of this maneuver being performed in a 1960 172?

Of course. However, that does not mean it is legal or smart.

The 172 may be able to stand the G forces, but that is not the only
limitation. The carburetor only works when right side up, for example.
A barrel roll should not be a problem, executed properly, but if you
screw it up then you might have some trouble. The 172 is allowed to do
spins, but it can be hard on the instruments, knocking them back and
forth from stop to stop. For that reason some FBOs insist that spin
training be done in other airplanes.

I suspect, however, that the real reasons the 172 is not certified for
aerobatics is Cessna didn't want the liability, the 172 has a
not-very-much-fun roll rate, and sooner or later some pilot would be
bound to do them with passengers and no parachutes.

Finally, if you are the sort of person who goes out and abuses other
people's property and tries to conceal it, I suspect that most of us
would not want you renting our planes.
--
Waddling Eagle
World Famous Flight Instructor


As I wrote, I own the plane. I do not and have not gone out and
abused other people's property. If I did, I wouldn't try to conceal
it, but thanks for the response.

I am very sorry. I did not mean to imply that you would do this. I was
speaking generally, not about you personally. I am embarrassed that I
said that.
--
Waddling Eagle
World Famous Flight Instructor

C J Campbell wrote:


The 172 may be able to stand the G forces, but that is not the only
limitation.ould not want you renting our planes.

Engine mount?

On May 3, 12:42 pm, The Visitor
wrote:
C J Campbell wrote:
The 172 may be able to stand the G forces, but that is not the only
limitation.ould not want you renting our planes.

Engine mount?

Engine mounts are good for 9 Gs. Somewhere in FAR 23, I think.

Dan

On 3 May 2007 13:03:07 -0700, wrote:

On May 3, 12:42 pm, The Visitor
wrote:
C J Campbell wrote:
The 172 may be able to stand the G forces, but that is not the only
limitation.ould not want you renting our planes.

Engine mount?

Engine mounts are good for 9 Gs. Somewhere in FAR 23, I think.

FAR 23 might not apply to a 172...it's old enough.

Ron Wanttaja