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Autogyro embarked in Battlships

Started by ysi_maniac, April 23, 2016, 02:04:19 PM

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jcf

Actually the artist makes reference to direct takeoff which was the term used by Cierva Autogiro in Britain
for what Pitcairn dubbed jump takeoff, which did allow vertical take-off of a sort, and I never said an autogiro
was incapable of vertical takeoff, I stated it couldn't hover;)

With direct/jump takeoff the rotor is spun up to speed with the blades in neutral pitch, once up to speed the drive to
the rotor is declutched and the blades are moved to a positive pitch that bites into the air which pulls the 'giro abruptly
off the ground and forward, at the top of the jump, (the AC-35/PA-36 jumped as high as 20'+ depending on conditions) the
blades automatically go to flight pitch and autorotation, with the propeller supplying the forward motion. Once the
bugs were worked out the systems worked well.

https://youtu.be/iAENPTmjBCg

As to 'giros with floats, the most famous photos are of the single float equipped C.30A which the test and service pilots
hated as they turned an already underpowered machine into a complete pig. The floats had steps because they were
standard aircraft floats and the C.30A used did not have direct/jump takeoff capability so it was still required to make
a takeoff run once the rotor was spun up to speed. Ditto the floats used on one of the USN Pitcairn XOP-1(PCA-2).

proditor

I made a couple for my USAS Edison in 1/700 like...6 years ago?  They're fun.  ;)

Pics are over here for a Catalina and a B-17 converted to Autogyros: http://www.whatifmodelers.com/index.php/topic,27095.msg419945.html#msg419945

Weaver

Quote from: joncarrfarrelly on May 10, 2016, 10:53:02 PM

As to 'giros with floats, the most famous photos are of the single float equipped C.30A which the test and service pilots hated as they turned an already underpowered machine into a complete pig. The floats had steps because they were standard aircraft floats and the C.30A used did not have direct/jump takeoff capability so it was still required to make a takeoff run once the rotor was spun up to speed. Ditto the floats used on one of the USN Pitcairn XOP-1(PCA-2).

If you do a Google image search on 'autogyros with floats' the vast majority of pictures you get are of modern ones and when I did this, I couldn't find one that didn't have stepped floats.
"Things need not have happened to be true. Tales and dreams are the shadow-truths that will endure when mere facts are dust and ashes, and forgot."
 - Sandman: A Midsummer Night's Dream, by Neil Gaiman

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 - Indiana Jones

jcf

Quote from: Weaver on May 13, 2016, 09:48:40 AM
Quote from: joncarrfarrelly on May 10, 2016, 10:53:02 PM

As to 'giros with floats, the most famous photos are of the single float equipped C.30A which the test and service pilots hated as they turned an already underpowered machine into a complete pig. The floats had steps because they were standard aircraft floats and the C.30A used did not have direct/jump takeoff capability so it was still required to make a takeoff run once the rotor was spun up to speed. Ditto the floats used on one of the USN Pitcairn XOP-1(PCA-2).

If you do a Google image search on 'autogyros with floats' the vast majority of pictures you get are of modern ones and when I did this, I couldn't find one that didn't have stepped floats.

Because none of them have jump takeoff capability, they have to make a takeoff run, thus they require stepped floats.
On a 'giro with jump takeoff you could have cylindrical floats or an unstepped boat hull as used on amphibious helicopters.
However, it would limit the 'giro pilot to always using the jump takeoff mechanism.

Sorry, Harold but despite what I've posted it seems that you still haven't grasped the technical reality of what an autogiro is and what it isn't.