737 emergency exits

[Genghis the Engineer]

I've just been on a there-and-back business trip on CSA 737s. Outbound a 737-500, and returning a 737-400. I noticed that although otherwise the cabin was superficially the same, the -400 had two emergency exists over the wing, whilst the -500 had only one. Given Boeing is well known for not implementing anything unless they've no choice, could anybody enlighten me as to the reason.

Just curious.

G

[Slasher]

bein only a 737-200/300 driver Genghis, I can only suggest the 90sec evacuation rule might apply here. The 400 carrys I think about 1/3rd more bums than the 500. Maybe during the cert process boeing proved only 1 overwing exit was enough to boot everyone out in time on the 500, (each additional exit denys the fitting of a revenue-generating seat immediatley ajacent to it), whereas the 400 mustve needed 2 exits.

Just my ejamakated guess.

[dolly737]

Genghis:

Slasher's guess is correct. It has to do with max seating capacity. This is also the reason why the -800 and the -900 have the same max seating capacity although the -900 cabin is a bit longer.

[Genghis the Engineer]

Thanks chaps, I consider myself duly enlightened.

G

[GlueBall]

Another refined overwing exit hatch feature of the "Next Generation" 73s is that they are hinged at the top and open outward. :p

[CaptainSandL]

Further to Dolly’s comments, the 900 max pax capacity is 189 (same as the –800) until it decides to fit type I doors, probably aft of the wing. This would put the max pax up to 220 with an 84Ton –900X. They might be looking very closely at this option with Airbus winning so many A320/321 orders.

[Slasher]

Amen SandL! We need Boeing to get its flamin act together to protect us from Airbus!

[eng1170]

Hear, hear Slasher - Bring On The Boeing's !!!

If it ain't Boeing - I ain't going !!