Posted: Tue Apr 24, 2012 5:25 pm Post subject: Mass and Balance
I thought I would share a handy formula that can be used for shifting masses around for PPL or CPL.
Weight to be shifted/ Total weight = Change in centre of gravity/ distance of weight to be moved
If you know any 3 you can get the other figure!
Example: The loaded mass of an aircraft is 1850lbs
the moment is 154,000
How much mass must be moved from the forward hold 40 inches aft of the datum to the rear hold which is 158 inches aft of the datum?
The CG limits are 86inches forward and 90 inches aft.
The change in CG is ( weight x arm = moment) 1850lbs x 83.24= 154000lbs
so the difference or change in CG is forward limit 86 inches minus 83.24 inches = 2.76 inches
The distance the mass has moved is 158 inches minus 40 inches = 118 inches.
?/ 1850 = 2.57/ 118
? = 43.27
Might come in handy " especially for all you airbus pilots"
I have just had a question very similar to this fired at me during an exam, I also had one in my PPL but didnt know the formula then so guessed it.
Trying to prepare for Radio Nav at the moment while retaining agk,met, performance,planning and m&b. Thanks for the turbine cd rom mate very useful. Popped down to see richard too at Bicester yetserday to run over traffic loads again (make sure im doing it right).
You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot vote in polls in this forum