DA20 Nose Wheel
Thread Starter
Safety First!
Joined: Jun 2001
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From: New Zealand
DA20 Nose Wheel
Can anybody tell me why the DA20 Katana's nosewheel is offset to the port side of the nose? In flight the castoring nose wheel turns to the right, wouldn't this create additional drag? There is no reason stated for this in the AFM.
Kermie
Kermie
Joined: Aug 2001
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From: UK Work: London. Home: East Anglia
Kermit -
No idea why the nosewheel is offset from the centreline, but may I offer a speculation on the second point? If the nosewheel is free-castoring, and assuming the centre of pressure is behind the pivot axis, it will of course "float" free to line up with the relative airflow. But behind a rotating pro, the relative airflow is actually skewed - cf. those ubiquitous diagrams of how slipstream "spirals" around the fuselage - so the lowest drag position may actually be with the nosewheel pointed off to one side.
A wind tunnel test (or some power-on then dead-stick formation flying!) would be an interesting test, but failing that rather extreme measure it might be interesting to "tuft" the nose of the aircraft with some strands of wool and gaffer tape and get an observer to see how the airflow lines up wit the engine running. Actually I suppose a partial tuft test could be done on the ground at, say, run-up power.
No idea why the nosewheel is offset from the centreline, but may I offer a speculation on the second point? If the nosewheel is free-castoring, and assuming the centre of pressure is behind the pivot axis, it will of course "float" free to line up with the relative airflow. But behind a rotating pro, the relative airflow is actually skewed - cf. those ubiquitous diagrams of how slipstream "spirals" around the fuselage - so the lowest drag position may actually be with the nosewheel pointed off to one side.
A wind tunnel test (or some power-on then dead-stick formation flying!) would be an interesting test, but failing that rather extreme measure it might be interesting to "tuft" the nose of the aircraft with some strands of wool and gaffer tape and get an observer to see how the airflow lines up wit the engine running. Actually I suppose a partial tuft test could be done on the ground at, say, run-up power.
Thread Starter
Safety First!
Joined: Jun 2001
Posts: 516
Likes: 0
From: New Zealand
STILL no reply from Diamond Aircraft, perhaps they don't care to explain to a mere non-aircraft owner.
Kermie
PS: CFI or WWW, is it possible to have a link to this put in the technical forum or should I post it again there myself?
[ 28 August 2001: Message edited by: Kermit 180 ]
Kermie
PS: CFI or WWW, is it possible to have a link to this put in the technical forum or should I post it again there myself?
[ 28 August 2001: Message edited by: Kermit 180 ]
