The simple answer to your question is as Bumblebee has already mentioned. You may well be way above your MLW and need the extra performance.
Infact you could well be returning from a max weight take-off in hot /high / humid conditions on one engine with significant terrain considerations. In that case you would want all the performance you can get!
Below MLW, flying around low flat terrain you may consider the exercise too time consuming or distracting for you to bother with at the time. That's your call on the day.
I just checked the Landing Climb performance figures (Gear Up, One Engine Inoperative, Go-Around Thrust, bleeds On) in the performance manual.
The B738 manual with Engine Bleeds Off allows you to increase the gross climb gradiant 0.2% (i.e. from say 3.0% gradient to 3.2% gradient).
The B734 makes no mention of a Bleeds Off climb gradient credit. Obviously it would be in the same order as the B738 (wouldn't it??).
I suppose it would be good to sit down one day and become familiar with some of the relevent numbers in the book with regards to gross weight vs climb gradient. Then you'll have a better idea whether or not having bleeds on/off will make or break your day (if you should ever be so unlucky).
cheers.
Last edited by Blip; 7th Jan 2005 at 22:52.