Endurance of aircraft
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Endurance of aircraft
Hi guys!
Recently upon arrival to UAAA, active TS, WS, mod turbulence were reported. So ATC directed us to holding pattern and asked us "Report your endurance and alternate aerodrome".
What does ATC mean by "report your endurance":
- time (extra fuel) that we can hold or wait before diversion, or
- total time (the fuel remaining) that aircraft can actually fly with actual fuel?
Captain responded "12 min, so we can hold for 12 min". Later ATC asked us again about our endurance for 3 times. Finally he asked us in russian, so I told him in russian "we can hold for 12 min and in total we can fly for 1h30min.
So, guys, am I wrong with my interpretation of "endurance"? Because I thought that "report your endurance" means that "how long are you able to wait before starting approach to land".
Recently upon arrival to UAAA, active TS, WS, mod turbulence were reported. So ATC directed us to holding pattern and asked us "Report your endurance and alternate aerodrome".
What does ATC mean by "report your endurance":
- time (extra fuel) that we can hold or wait before diversion, or
- total time (the fuel remaining) that aircraft can actually fly with actual fuel?
Captain responded "12 min, so we can hold for 12 min". Later ATC asked us again about our endurance for 3 times. Finally he asked us in russian, so I told him in russian "we can hold for 12 min and in total we can fly for 1h30min.
So, guys, am I wrong with my interpretation of "endurance"? Because I thought that "report your endurance" means that "how long are you able to wait before starting approach to land".
I understand that the ATC want to know total endurance. I've always reported that.
Maybe it would be useful to check in the definitions section of the country's air regulations.
Maybe it would be useful to check in the definitions section of the country's air regulations.
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It is time remaining to fuel exhaustion.
How have we arrived at a point where a captain and copilot between them could not give the correct answer to this fundamental request from ATC.
How have we arrived at a point where a captain and copilot between them could not give the correct answer to this fundamental request from ATC.
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I submit that it's not a matter of "unable" to give the answer, but that it takes time after an unusual request to do the math.
Some pilots may try to overcomplexify the calculation. I would rather simplify it as much as possible: I know that at landing weight a 744 can cruise or hold at just about any altitude, in any configuration, at 2,500 Kg/hr/engine, or 10 T/hr or less. That makes calculations simple and conservative. If I'm at my [sometimes] minimum fuel over destination of 7T, I have about 45 minutes to flameout.
Some pilots may try to overcomplexify the calculation. I would rather simplify it as much as possible: I know that at landing weight a 744 can cruise or hold at just about any altitude, in any configuration, at 2,500 Kg/hr/engine, or 10 T/hr or less. That makes calculations simple and conservative. If I'm at my [sometimes] minimum fuel over destination of 7T, I have about 45 minutes to flameout.
ATC should have been asking for your latest divert time if that is what they wanted to know. From what the OP is suggesting they just wanted to know how long they were going to be in their airspace before they had to go to the alternate. To ask for their endurance would seem to be irrelevant in this instance.
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From the Pilot/Controller Glossary in the US FAA AIM:
FUEL REMAINING− A phrase used by either pilots or controllers when relating to the fuel remaining on board until actual fuel exhaustion. When transmitting such information in response to either a controller question or pilot initiated cautionary advisory to air traffic control, pilots will state the APPROXIMATE NUMBER OF MINUTES the flight can continue with the fuel remaining. All reserve fuel SHOULD BE INCLUDED in the time stated, as should an allowance for established fuel gauge system error.
