Choosing Cruising altitude
 

Is there a formula for choosing the cruising altitude in relation to total flight distance, just as there is one for calculation TOD?
I'm particular interested in B737-400 info, but i would also like to know if there is a rule of thumb formula that applies to all aircraft.
Since airliners cruise @ approx FL300-350, TOD is about 100NM from destination. I'm a little confused as to how you choose cruising Alt for short flights <100nm.
Capt. Manuvar

In the case of the 737 Boeing produce a graph which shows optimum cruise level/distance.

We used to take the distance in NM, knock off the last digit and use the first two as your FL, 235nm = FL230 etc. up to your service ceiling.

Obviously it will depend on a few things, like MSA and ATC, aircraft etc.
From LGW to Cardiff in a B737-200 FL150 once west of London was quite common as this fitted in with the London TMA requirements.

The graph is not to be found in yo' pilot's books but in the AFM or performance/planning manual instead.

Or, better yet, in those lovely CAPs for JAA exams. Without 'em I'd had been doomed to fail.

PanAmerican used to provide very good data with their B707-300 fans performance quick reference checklists...available on all B707 aircraft.
This provided the needed data to perform these rather short flight sectors, and indeed included info on diversions that would otherwise take ages to find in the AFM.

I have personally never noticed this info concisely provided, with the possible exception of BOAC...nee BA.

i do it a very easy way . it's to add 20% to the total distance.

ie; 120nm.
20% = 24
120=24= 144.
therefore depends which way u're heading east or west.

east 15000 or fl150
west 14000 or fl140.
Hope this works...