Fokker speed

[Freek Vandeursen]

A question about flightplanning for the Fokker 100. I noticed that my flights with the Fokker always take longer than the flight briefing predicts. So on what speed is this prediction based? When using the Vatsim prefile system the True Airspeed is entered as 462kts, is this also what the flight time calculation uses? 462 is quite a bit too high for the Fokker anyway. On cruise level with the standard cost index of 50 a TAS of 400kts would be more accurate.

 

[Peter Schindler]

So on what speed is this prediction based? When using the Vatsim prefile system the True Airspeed is entered as 462kts, is this also what the flight time calculation uses?

Yes, exactly. The value is entered in the performance data of each aircraft type. It could be easily changed. However, looking on

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they indicate a cruise speed of 453 kts - although that's max cruise, I guess.

If you'd like to be our test dummy, I suggest we set the average TAS of the F100 to 410 kts now, and you tell us after a few flights if that gives you better results or still too much. Thanks for testing, already.

Peter

 

[Freek Vandeursen]

That would be great Peter. A standard cost index of 50 gives me a Mach 0.7 cruise which under normal circumstances should relate to around 400kts TAS. Max cruise speed is Mach 0.75, which will be around 430kts TAS.

I don't know how the Digital Aviation Fokker relates to the real world numbers, but in my simulator there's no way I can get 462kts without significant tailwind.

And I'll happily be your guinea pig for some test flights.