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Old 02-17-2008, 03:14 PM
Finley Atherton Finley Atherton is offline
 
Join Date: Nov 2005
Location: AUSTRALIA
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Default Nose Wheel Weight Question

Another thread; http://www.vansairforce.com/communit...ad.php?t=26893 has got me thinking about the nose wheel weight issue. Solo in my 9A with full fuel will put a calculated 341 lb on the nose wheel. I would need to put about 30 lb in the baggage compartment to bring it back to Vans max of 325 lb. I need to use at least moderate braking when landing on my short farm strip and this naturally throws extra weight on the nose wheel. This might be a silly question, but what would be less stressful on the nose gear? Hard braking with an aircraft that is 30 lb heavier to comply with the 325 lb static limit, or hard braking with an aircraft 30 lb lighter but with 16 lb more static weight on the nose wheel??

Fin
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  #2  
Old 02-17-2008, 03:59 PM
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plehrke plehrke is offline
 
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Location: Defiance, MO
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Default Less Weight on the nose Gear Better

The stall speed for the 9A is 5 mph faster for the difference in weight from solo to max gross weight according to Van's web site. That is only 1 mph faster for 50 lbs. Remember the kentic energy you need to disapate in braking is 1/2mv^2. The 30 lbs and 1 mph increase braking energy by about 5% (0.5*1400*60^2 vs 0.5*1430*61^2). The distance the cg is above the main tire contact point is about 2/3 the distance from the nose gear to the main gear therefore the 5% increase in energy translates to ~3% increase on the nose landing gear. Your weight on the nose gear difference is 5% (16/325).

Therefore weight on the nose gear is worse than the increase weight of the plane with the ballast.
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  #3  
Old 02-17-2008, 04:26 PM
Finley Atherton Finley Atherton is offline
 
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Default

Quote:
Originally Posted by plehrke View Post
The stall speed for the 9A is 5 mph faster for the difference in weight from solo to max gross weight according to Van's web site. That is only 1 mph faster for 50 lbs. Remember the kentic energy you need to disapate in braking is 1/2mv^2. The 30 lbs and 1 mph increase braking energy by about 5% (0.5*1400*60^2 vs 0.5*1430*61^2). The distance the cg is above the main tire contact point is about 2/3 the distance from the nose gear to the main gear therefore the 5% increase in energy translates to ~3% increase on the nose landing gear. Your weight on the nose gear difference is 5% (16/325).

Therefore weight on the nose gear is worse than the increase weight of the plane with the ballast.
WOW, I sort of understand! Thanks for the expert answer.

Fin

Last edited by Finley Atherton : 02-17-2008 at 05:16 PM.
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