Q: PBY

http://www.sa-transport.co.za/aircra...by-5a_ra98.JPG

OK, I've seen pictures of PBYs with;

1. All three gears down and the outer potoons down,
2. All gears down, potoons up,
3. Gears up, potoons down,
4. and now the above picture with only the main gears down, but nose
wheel still tucked in and pontoons still up or maybe no pontoons.

My question are; are the gears controlled individually, are the
pontoons controlled separately, are the font and main gears controlled
separately also? If so, why?

Wil

"William Hung" wrote in message
...
http://www.sa-transport.co.za/aircra...by-5a_ra98.JPG

OK, I've seen pictures of PBYs with;

1. All three gears down and the outer potoons down,
2. All gears down, potoons up,
3. Gears up, potoons down,
4. and now the above picture with only the main gears down, but nose
wheel still tucked in and pontoons still up or maybe no pontoons.

My question are; are the gears controlled individually, are the
pontoons controlled separately, are the font and main gears controlled
separately also? If so, why?

I would say the above mentioned aircraft is about to have a very noisy
runway landing, if you get my drift. I vote for gear failure.
--
Jim in NC

Morgans wrote:
"William Hung" wrote in message
...
http://www.sa-transport.co.za/aircra...by-5a_ra98.JPG

OK, I've seen pictures of PBYs with;

1. All three gears down and the outer potoons down,
2. All gears down, potoons up,
3. Gears up, potoons down,
4. and now the above picture with only the main gears down, but nose
wheel still tucked in and pontoons still up or maybe no pontoons.

My question are; are the gears controlled individually, are the
pontoons controlled separately, are the font and main gears controlled
separately also? If so, why?

I would say the above mentioned aircraft is about to have a very noisy
runway landing, if you get my drift. I vote for gear failure.

Maybe it's a case of one gear (nose in this case) retracting before the others? I've
noticed many airplanes where each gear retracts at different rates, or one part of the
gear retracts before the others. I think it just has to do with how the hydraulics are
run and all that. Not sure about this case though.

On multiple occasions, I've seen F-15 nosewheels fail to retract; most of the time they
cleared it by cycling the gear, but twice I noticed it not retract even after cycling. I
guess the pilots really had to pull the power off quick so they doesn't overspeed.

On Feb 19, 7:03�pm, Bob Martin wrote:
Morgans wrote:
"William Hung" wrote in message
...
http://www.sa-transport.co.za/aircra...by-5a_ra98.JPG

OK, I've seen pictures of PBYs with;

1. All three gears down and the outer potoons down,
2. All gears down, potoons up,
3. Gears up, potoons down,
4. and now the above picture with only the main gears down, but nose
wheel still tucked in and pontoons still up or maybe no pontoons.

My question are; are the gears controlled individually, are the
pontoons controlled separately, are the font and main gears controlled
separately also? �If so, why?

�I would say the above mentioned aircraft is about to have a very noisy
runway landing, if you get my drift. �I vote for gear failure.

Maybe it's a case of one gear (nose in this case) retracting before the others? �I've
noticed many airplanes where each gear retracts at different rates, or one part of the
gear retracts before the others. �I think it just has to do with how the hydraulics are
run and all that. �Not sure about this case though.

On multiple occasions, I've seen F-15 nosewheels fail to retract; most of the time they
cleared it by cycling the gear, but twice I noticed it not retract even after cycling. �I
guess the pilots really had to pull the power off quick so they doesn't overspeed.- Hide quoted text -

- Show quoted text -

Some civilian owned PBYs have added valves to allow retraction of one
gear at a time for servicing. The tip pontoons are on a seperate
system, a single drive motor in the pylon driving shafts in the
leading edge of the wing.

On Feb 19, 10:25Â*pm, " wrote:
On Feb 19, 7:03�pm, Bob Martin wrote:





Morgans wrote:
"William Hung" wrote in message
....
http://www.sa-transport.co.za/aircra...by-5a_ra98.JPG

OK, I've seen pictures of PBYs with;

1. All three gears down and the outer potoons down,
2. All gears down, potoons up,
3. Gears up, potoons down,
4. and now the above picture with only the main gears down, but nose
wheel still tucked in and pontoons still up or maybe no pontoons.

My question are; are the gears controlled individually, are the
pontoons controlled separately, are the font and main gears controlled
separately also? �If so, why?

�I would say the above mentioned aircraft is about to have a very noisy
runway landing, if you get my drift. �I vote for gear failure.

Maybe it's a case of one gear (nose in this case) retracting before the others? �I've
noticed many airplanes where each gear retracts at different rates, or one part of the
gear retracts before the others. �I think it just has to do with how the hydraulics are
run and all that. �Not sure about this case though.

On multiple occasions, I've seen F-15 nosewheels fail to retract; most of the time they
cleared it by cycling the gear, but twice I noticed it not retract even after cycling. �I
guess the pilots really had to pull the power off quick so they doesn't overspeed.- Hide quoted text -

- Show quoted text -

Some civilian owned PBYs have added valves to allow retraction of one
gear at a time for servicing. The tip pontoons are on a seperate
system, a single drive motor in the pylon driving shafts in the
leading edge of the wing.- Hide quoted text -

- Show quoted text -

Cool, all very plausible explanations.

Thanks guys,
Wil

Originally Posted by Bob Martin

Morgans wrote :
My question are; are the gears controlled individually, are the
pontoons controlled separately, are the font and main gears controlled
separately also? If so, why?

Maybe it's a case of one gear (nose in this case) retracting before the others? I've
noticed many airplanes where each gear retracts at different rates, or one part of the
gear retracts before the others. I think it just has to do with how the hydraulics are
run and all that. Not sure about this case though.

Gears :
You are right.
It is a sequence, to lighten the burden of the pump :
1. Nose gear (283 lb),
2. (Right) main gear (747 lb),
3. (Left) main gear (747 lb).

You clearly see it on videos.



Floats :
Both floats are actuated together by a single power gear box.

J-Chris.

Originally Posted by William Hung[_2_]

http://www.sa-transport.co.za/aircra...by-5a_ra98.JPG

OK, I've seen pictures of PBYs with;

1. All three gears down and the outer potoons down,
2. All gears down, potoons up,
3. Gears up, potoons down,
4. and now the above picture with only the main gears down, but nose
wheel still tucked in and pontoons still up or maybe no pontoons.

My question are; are the gears controlled individually, are the
pontoons controlled separately, are the font and main gears controlled
separately also? If so, why?

Wil

I guess that picture is just after take-off and the nose gear retracted first. (even though the plane appears slight nose down).

The Registration number shown under the picture is wrong, as only US registrations start with N and they can have up to 5 places in the registration. You can only have two letters in the registration, and if there are letters they have to be in the last positions. (A number can never follow a letter - except for the starting "N" of course).

Here is a photo on Wiki that shows how the outer wing floats
(pontoons) can swing up, so that the pontoon becomes the wingtip.

http://upload.wikimedia.org/wikipedi...F_Catalina.JPG

That has got to be the case with your photo. A larger question is:
where's the tail wheel? Blue skies! -- Dan Ford


On Mon, 18 Feb 2008 18:30:54 -0800 (PST), William Hung
wrote:

http://www.sa-transport.co.za/aircra...by-5a_ra98.JPG

OK, I've seen pictures of PBYs with;

1. All three gears down and the outer potoons down,
2. All gears down, potoons up,
3. Gears up, potoons down,
4. and now the above picture with only the main gears down, but nose
wheel still tucked in and pontoons still up or maybe no pontoons.

My question are; are the gears controlled individually, are the
pontoons controlled separately, are the font and main gears controlled
separately also? If so, why?

Wil

Blue skies! -- Dan Ford

Claire Chennault and His American Volunteers, 1941-1942
new from HarperCollins www.FlyingTigersBook.com

On Feb 25, 4:24 pm, Cubdriver usenet AT danford DOT net wrote:
Here is a photo on Wiki that shows how the outer wing floats
(pontoons) can swing up, so that the pontoon becomes the wingtip.

http://upload.wikimedia.org/wikipedi...K_RNZAF_Catali...

That has got to be the case with your photo. A larger question is:
where's the tail wheel? Blue skies! -- Dan Ford

On Mon, 18 Feb 2008 18:30:54 -0800 (PST), William Hung



wrote:
http://www.sa-transport.co.za/aircra...by-5a_ra98.JPG

OK, I've seen pictures of PBYs with;

1. All three gears down and the outer potoons down,
2. All gears down, potoons up,
3. Gears up, potoons down,
4. and now the above picture with only the main gears down, but nose
wheel still tucked in and pontoons still up or maybe no pontoons.

My question are; are the gears controlled individually, are the
pontoons controlled separately, are the font and main gears controlled
separately also? If so, why?

Wil

Blue skies! -- Dan Ford

Claire Chennault and His American Volunteers, 1941-1942
new from HarperCollinswww.FlyingTigersBook.com

It is a tricycle geared aircraft Dan...the question is...where is the
nose gear!

Hawkeye wrote:
On Feb 25, 4:24 pm, Cubdriver usenet AT danford DOT net wrote:
Here is a photo on Wiki that shows how the outer wing floats
(pontoons) can swing up, so that the pontoon becomes the wingtip.

http://upload.wikimedia.org/wikipedi...K_RNZAF_Catali...

That has got to be the case with your photo. A larger question is:
where's the tail wheel? Blue skies! -- Dan Ford

On Mon, 18 Feb 2008 18:30:54 -0800 (PST), William Hung



wrote:
http://www.sa-transport.co.za/aircra...by-5a_ra98.JPG

OK, I've seen pictures of PBYs with;

1. All three gears down and the outer potoons down,
2. All gears down, potoons up,
3. Gears up, potoons down,
4. and now the above picture with only the main gears down, but nose
wheel still tucked in and pontoons still up or maybe no pontoons.

My question are; are the gears controlled individually, are the
pontoons controlled separately, are the font and main gears controlled
separately also? If so, why?

Wil

Blue skies! -- Dan Ford

Claire Chennault and His American Volunteers, 1941-1942
new from HarperCollinswww.FlyingTigersBook.com

It is a tricycle geared aircraft Dan...the question is...where is the
nose gear!

The nose gear is in what's probably some sort of a sealed compartment within
the forward part of the pontoon/fuselage. Just Google "PBY Photos" and
you'll see pictures of it on the ground.

George Z.