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Old 21st October 2023 | 12:36
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QuebecLima
 
Joined: Oct 2023
Posts: 7
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From: Belgium
Originally Posted by ant1
Let me take a shot at It. As someone already told you, you applied the correction in the wrong direction. You are flying FL's hence your altimeter is set to 1013,2 hPa. If you wind down that setting to your QNH of 950 hPa, guess what happens to your altimeter reading. Hint: you end up with 11.110 ft if I recall your math correctly. The MORA is 12.600ft and at that altitude, above 5.000 ft, it gives you 2000 ft clearance. Therefore the highest obstacle rises up to 10.600ft. At 11.110 ft you will clear that obstacle in a way that would grant you a tea no biscuits meeting at the Chief Pilot's office at any reputable Airline. But hey, you'll be alive unless you throw in some wind and low temperatures into the equation.

Now let's see If I can get the M&B quiz right.

You must meet the three following restrictions:

1) DOM+TOF+Payload <= MTOM
2) DOM+Payload <= MZFM
3) DOM+Payload+TOF-trip <= MLM
Additionally:
4) DOM+Payload+FOB <= MRM

That gives you:

1) Payload <= MTOM-DOM-TOF
2) Payload <= MZFM-DOM
3) Payload <= MLM-DOM-TOF+trip
4) Payload <= MRM-DOM-FOB

TOF = Takeoff fuel
trip = trip fuel
FOB = ramp fuel (off block total fuel on board)
MRM = Max Ramp Mass

You take the lowest figure and that will be your allowed max payload

Note: on lighter aircraft MRM=MTOM
Ah thanks, this is exactly what I needed !
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