Seat occupancy limits
I've been banging my head up against seat occupancy limits over the last few days, and I'd be very interested in anybody else's experience of the subject.
In most of the codes, seat occupancy limits are in three places. Para 25 for W&CG purposes, para 562 for test purposes, and para 785 for design purposes. When comparing the various codes, I get the following:-
Parts 25, 27, 29, 31
77 kg / 170 lb for all purposes.
Part 23
(W&CG purposes) 77kg (170 lb) for norm/comm, 86kg (190lb) for util/aero
(test purposes) 77kg (170 lb)
(design purposes) 77kg (170lb) for utility, 98kg (225lb) for all other cats.
Part VLA
86kg / 170 lb for all purposes.
Part 22
110kg / 242lb for all purposes.
The reason for one inconsistency is clear, which is part 22 - it's a glider code and the 110kg allows for a parachute. That doesn't worry me at-least.
What does worry me is...
- Why is part 23 internally consistent?
- Has it not occurred to anybody that very few adults these days weigh under 77kg?
- Why is is appropriate for a VLA non-aerobatic aeroplane to use 86kg, yet a 23 non-aerobatic 98kg? They fly the same role, both in the public transport (OK, training) role.
- Is there a good reason why training helicopters and aeroplanes use different crash limits?
- Why is there no form of disclaimer or notification used anywhere that seats - either crew or pax - are designed for a specific weight which is certainly only in the mid-high percentile range?
One can find more and more questions the more one looks into this.
Does anybody have any thoughts or experiences that might help make any kind of sense out of this?
G