The hand computation of airplane performance, namely time, fuel and Payload, to accomplish a specific mission, is time consuming because it is an iterative process.
The complexity of airplane performance is such that values set for any variable will interact wlth the other variables making the solution complex. Typically, the analyst is faced with the problem of computing the performance of one or more airplanes or of one or more configurations of the same airplane over several routes.
Depending on the number and combinations of the above parameters it can take hours or days of hand calculations. Usually these calculations are made using a specific set of ground rules, which are provided by the operator (airline) and/or the analyst of a consulting firm and/or of the airplane manufacturer. These ground rules consist of airplane characteristics, a set of study mission rules, airports and routes characteristics.
Airplane characteristics consist of capacity and basically weights definitions and limits. Weights such as taxi, takeoff, landing and operating weight must be established as well as fuel and cargo capacity.
Study mission rules consist of definitions of taxi and takeoff time, fuel and distance, climb and descent schedules, cruise procedures and reserve fuel rules. On board fuel load at takeoff includes enough fuel to fly to the destinatlon plus reserve fuel to fly to an alternate airport and enough additional fuel to meet potential traffic and weather problems.
Airport characteristics are defined as those items necessary to establish the maximum allowable takeoff weight of any alrplane that is to be studied from each airport included in the study. Items referred to included in airport characteristics are airport code, runway elevation, runway length, surface temperature an alternate airport distance.
Route characteristics consist of city pair codes, distances to be flown and winds and temperatures to be used on route. With all the above rules and information the analyst is faced with calculation of block fuel, block time and, above all, payload that can be carried on each route.
If you want to know how we in Albatros have tackled and solved the problem briefly described here, go on reading by pressing the continue button.