HelloThe manual suggests the following method for fuel calculation:Taxi Burn: 100First Hour of Flight: 1200Subsequent hours: _____(multiply hours by 1000lbs)Landing Fuel: 800Reserve need:_____Total Fuel Required: ______However what if i dont know the specific time duration of flight ? What then ? how shall i plan my fuel consumption?Also in page 538 in the AOM file...i didnt understand this instruction "Select the TRIP PLAN field with the line select keys and INSERT

You probably have a rough idea within +/-15 minutes. That will do.At least you should be aware of that before you fly.

The FSX flight planner will give you a rough estimate of duration. Or you could work it out based on a cruise TAS of 290 odd knots. That means, for example, that a 500nm trip should take approx 1.7 hours. Give yourself another .2 or so for departure and arrival. Perhaps more if you expect a lot of vectors, or long SIDS/STARS (routing on arrival/departure).

thank guys.however how do real world pilots calculate their fuel ?also ca you answer the 2nd section of my questionthanks in advance,Greg.

Once again, they use math.Real world pilots calculate their fuel the same way as above, and dont forget to factor in winds. You figure out how far you're flying and how fast you're flying (taking winds into account). That will give you how much fuel you need, then you add in extra fuel such as the 800 lbs reserve and any additional fuel for holding, missed approaches, and diversions to your alternate if you anticipate any of that. But back to your primary question, you need to know what your trip duration is, otherwise you cant determine how much fuel you will need.I dont know about your second question. I'm doing a flight right now and I am unable to select anythign at all in the trip plan page, all the data is automaticlly there.

however how do real world pilots calculate their fuel ?

In the real world this task is not done by pilots, but by dispatchers.The dispatcher relies on computer software that combines a very accurate aircraft performance database, the ability to download current winds aloft and temperature data, and the ability to take into account a multitude of other operational considerations, like MEL/CDL penalties, rolling/static takeoff penalties, runway data (length/slope/grooved/contamination, etc), obstacle data, etc.From this information, the computer gives preliminary data such as ETE, fuel burn, required fuel, MTOW, MLW, optimum cruise altitude, etc.If necessary, from this preliminary information the dispatcher will then amend the ATC routing, change the climb/decent profile, change the cruise speed, change the cruise altitude, add additional fuel, or any number of things, then recompute the data again. This cycle can occur anywhere from 1 to 10 times depending on the results. Then the dispatcher generates the "release" that is the official plan for the flight.If the pilot wants to change something, he calls the dispatcher, and if they both agree that a change is needed or desirable, an amended release is issued. Usually, they like to add additional fuel.Its a very complex process, and without all of the data and integrated tools, it's nearly impossible to accurately simulate. Unless you want to buy something like F.O.C., which as about as close to real dispatch software as you'll find, your best bet is to simply use the rule of thumb mentioned in the FCOM for estimating fuel requirements.Nick