View Full Version : Door inoperative MEL

25th Sep 2007, 17:52
Okay, it's time to whip out your calculators and help me with a problem I'm having. First you will have to download FODCOM 8/99 from the CAA website here: http://www.caa.co.uk/application.aspx?catid=33&pagetype=65&appid=11&mode=detail&id=306

The scenario I am looking at is: A 8-door widebody aircraft. Door 1, 2 and 4 are Type A doors and Door 3 is a Type I. Door escape ratings (110) are the more limiting value for Doors 1,2 and 4 (raft capacity is greater); but for Door 3, as it is a Type I door does not have a raft. The Maximum Approved Passenger Seating Configuration is 240 seats and Zone A has 12 seats, Zone B 96 seats and Zone C 132 seats. Zone A is a low density zone (premium class) so Zone B passengers can use door 1 in the event of door 2 being inoperative. But Zone B is the start of cattle class so Zone B cannot skip door 3 to go to door 4 and Zone C cannot skip door 3 to go to door 2 (calculation-wise).

Where I keep getting stumped is for example, when Door 1 is inop, MAPC is 220, which should mean a 20 seat reduction (MAPSC-MAPC=20.)(right?) But when I look at how Zone C is configured, I can only get 110 out of the 132 pax out Door 4, which would mean 22 seats being blocked. So which is it 22 or 20?:ugh: I can't get anybody out Door 3 because the raft capacity is 0. Where is my calculations going awry?

Why am I doing all this? Well, I think my company MEL is not set up right and might need fixin'.

25th Sep 2007, 20:30
Your aircrafts total seating capacity is 240 pax.
Your doors allow 375 to safely exit.
Your rafts only fit 330 so this becomes the max allowable config.
Now Door 1L is out of action. You instantly lose 110 from that door pair.
330-110 = 220.
As your max pax load is 240 but you now only have raft space for 220 you must block out 20 seats.

Note - Don't confuse raft space with door capacity. Doesn't matter which doors they leave by they'll swim to the nearest raft (in theory).