Hello all,Will some of you experienced fliers tell me the method you use to determine a flight level? I am aware of the east-west requirements.I guess what I am after is..on a 400 mi. trip for instance, would you fly at 330 fl or 370 fl. How much of the trip is spent in climb? Would a 1200 mi trip make any difference? I am not really looking to find the most economical just a possible ratio of distance to altitude.Thanks Sinbad

A 400 mi trip is short indeed for a 763, but I have an AirDo video of a 767-300 and they fly between Tokyo and Sapparo, which is just over 400 miles. In the first flight they were told to climb to FL410 by atc due to traffic conjestion at their original planned cruise altitude and they achieved the climb in 14 mins and in all flights they never flew below FL370.I guess with such a light weight for the trip the 763 can climb like a rocket. I noticed a climb rate of 6000fpm on the VSI and between 3000 and 4000 fpm at the higher altitudes.Regards,Van LatendresseYeoDesigns/AFG GroupPanel/FDE Designer

The cruising level depends on several factors, including weight, winds, temperature, trip distance and ATC requirements.The 767 Perfomance Manual contains charts titled 'Altitude Selection' to ascertain which level to use. Sydney to Melbourne is only approximately 385nm, and we utilise the Boeing 767-238(ER), -336(ER) and -338(ER) on the route. Flight plans usually have FL380 to Melbourne and FL390 back. If the aircraft is heavy FL370 may be planned for the return. In reality the southbound leg is often flown into strong headwinds so as low as FL280 is flown to optimise the TAS and minimise the headwind in order to achieve schedule. Northbound the aircraft is climbed to optimum level to take advantage of tailwinds. This is only impeded if a Virgin Blue 737 is blocking the level (the 737 is quite a bit slower in cruise than the 767).I hope this is the kind of information you were after!

Thanks fellas, that was the kind of info I was looking for.Sinbad

Also, the FMC will tell you the optimum & max cruise levels on the VNAV page.