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Old 26th September 2007 | 19:00
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yellowsubmarine
 
Joined: Aug 2007
Posts: 52
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From: Madrid
Answer to no.1????

I've had a go at no.1......the answer i get is 22.5% mac although i expect to be corrected.

Is tough to explain without drawing the diagram but here goes......

Balane arm = the dist. from the datum to C og G

This makes your C of G (working in cm) 300 aft of datum. It is also 25% mac so Le mac = 250 and Te mac = 450

your are adding 160 Kg onto the Le mac position (50 cm fore of C of G). I then pressumed that because the fuel is added onto origional C of G position it makes no difference to final position except in overall weight of the a/c.

So....using little m over big M = little d over big D:

M = 1,200 (bem) + 160 (pilot and pax) + 95 (fuel, this may be inaccurate)

m = 160 (pax)

D = 50 (cm)

d = ? 160/1455 x 50 = 5.5cm subtract this from origional C of G because the weight is added fore of origional.

Finally 45cm of 200 cm = 22.5%

This maybe horribly wrong and i stand to be correted but i hope it helps. Would have a look at others but should really be revising Met...(very easily side-tracked). good luck, YS
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