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A320 family nosegear canted forward

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A320 family nosegear canted forward

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Old 25th Jan 2009, 19:53
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A320 family nosegear canted forward

I operate A320 aircraft and have wondered why the nosegear leg is canted forward.
From ramp observation, the design isn't copied on any other Airbus, or Boeing.
It appears to transfer all the load onto the inner tyre during turns, and seems to work against the trailing-arm effect for a loss-of-hydraulics landing.
Anyone know the technical reason for the unique layout?
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Old 26th Jan 2009, 01:27
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To expedite tire changes? In all seriousness, the Douglas tiwns, DC-9, etc, also had some forward cast, not very noticeable due to a shorter gear leg. FWIW the Airbus main gear legs are canted aft, no doubt to absorb my earth-shaking landings straight-up-and-down.

Excellent question.
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Old 26th Jan 2009, 07:08
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Originally Posted by rooaaiast
Anyone know the technical reason for the unique layout?
The wheels return freely to the center position. (inclination is 9°)
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Old 26th Jan 2009, 10:23
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Think the BAC 1-11 had a similar layout. Like the man says, quick wheel change without the need of a jack.

Never did it myself of course.
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Old 26th Jan 2009, 13:01
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Not unique, and the idea dates back to at least the Lockheed Constellation (ca. 1940).

Last edited by barit1; 26th Jan 2009 at 15:00.
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Old 26th Jan 2009, 13:45
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Originally Posted by IFixPlanes
The wheels return freely to the center position. (inclination is 9°)
Sounds perfectly plausible.
In which case the idea goes back as far as the invention of the bike
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Old 26th Jan 2009, 14:53
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Everything you'll ever need to know about landing gear geometry - apart from why nose legs may be canted.

http://www.ae.metu.edu.tr/~ae451/LandingGear.pdf
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Old 27th Jan 2009, 02:29
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I think you will find all Douglas tricycle landing gear aircraft have canted nose gears (DC4 thru MD11). I always understood it was for caster similar to a bicycle or motorbike. On Douglas aircraft the center of the nose wheel axle was mounted on the centerline of the inner cylinder whereas other designers used a trailing axle to achieve caster ie. the axle was behind the centerline of the oleo strut thus obtaining caster effect like a trolley wheel.
Having said that I don't know why the A320 family is the only Airbus product to use a canted nose gear.
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Old 27th Jan 2009, 21:57
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Here's one of three Lockheed 12-A's fitted with fixed tri-gear. This one was known as a C-40B (USAAC - 1939).

http://www.aerofiles.com/lockheed-c40b.jpg

(I note they didn't want to worry about tail strikes - )

Last edited by barit1; 28th Jan 2009 at 13:46.
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Old 28th Jan 2009, 07:17
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Bad idea really, had the same canted nosegear on the MD80. During tight turns, as previously mentioned, the outside nosewheel would be clear of the ground, providing minimal steering authority, on a wet or icy ramp this quickly became nonexistent
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Old 28th Jan 2009, 13:49
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Pure speculation - Do you think this may have been a factor in the CO 735 departing the runway at KDIA on TO?
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Old 28th Jan 2009, 17:37
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barit1,

Talk about the potatoe in a fruit party...
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Old 29th Jan 2009, 02:33
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Well no, Boeing's do not have canted nosegear
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Old 29th Jan 2009, 12:33
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I withdraw my speculation - more homework was needed.
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