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Quoting Flaps30 (Thread starter): but I always assumed my aircraft was departing under full power. |
Quoting Flaps30 (Thread starter): Why would they takeoff on anything but full power? |
Quoting Flaps30 (Thread starter): It seems to me there are less options in an emergency at a reduced power setting. |
Quoting Flaps30 (Thread starter): I have been hearing the term "full power takeoffs" alot lately. Forgive me for sounding naive, but I always assumed my aircraft was departing under full power. Why would they takeoff on anything but full power? Whats the benefit of taking off under reduced power aside from the obvious fuel burn. It seems to me there are less options in an emergency at a reduced power setting. |
Quoting Vikkyvik (Reply 2): burns less fuel as you stated. |
Quoting Vikkyvik (Reply 2): I don't know if that's an FAA requirement, though. |
Quoting WILCO737 (Reply 3): There are people still of different opinions. You need longer to reach acceleration height, so you have longer take off power until you set climb thrust. And the climb thrust is reduced as well, so you reach your cruising level later as well which cost you more fuel and you climb slower. |
Quoting Vikkyvik (Reply 4): Ah, that's a good point. Although couldn't your climb thrust setting still be the same as for a full-power takeoff? In which case, you're only "losing" the fuel you'd use from takeoff to throttle-back to climb. Or is the climb thrust setting always also reduced? |
Quoting Flaps30 (Thread starter): Whats the benefit of taking off under reduced power aside from the obvious fuel burn. |
Quoting Flaps30 (Thread starter): It seems to me there are less options in an emergency at a reduced power setting. |
Quoting Vikkyvik (Reply 2): There are situations in which a full-power takeoff is required - for instance, a short runway. |
Quoting Vikkyvik (Reply 4): Although couldn't your climb thrust setting still be the same as for a full-power takeoff? |
Quoting Vikkyvik (Reply 4): Or is the climb thrust setting always also reduced? |
Quoting WILCO737 (Reply 5): Sure you can do that, but then it could happen that the "full power" climb thrust his higher than the reduced take off thrust. That means reaching acceleration (thrust reduction) height that the engine N1 increases. |
Quoting Mir (Reply 8): Quoting Flaps30 (Thread starter): It seems to me there are less options in an emergency at a reduced power setting. You can always push the throttles forward if something happens. |
Quoting HAWK21M (Reply 6): Some Airports have noise restrictions too,which nessistate lower thrust settings. |
Quoting PGNCS (Reply 10): This is uncommon, but not unheard of (MD-90 for example.) |
Quoting WILCO737 (Reply 12): Quoting PGNCS (Reply 10): This is uncommon, but not unheard of (MD-90 for example.) Can happen on the 737 if you use max deration for take off and select full CLB thrust, then the N1 increases. usually the 737 uses CLB - 2 then and the N1 reduces slightly, but if you select CLB, then the N1 increases. Uncommen - yes, but possible. |
Quoting PGNCS (Reply 13): Thanks for the info. I only flew classic 737's and it was a while back. You are talking about the 737NG, right? I have |
Quoting WILCO737 (Reply 14): Quoting PGNCS (Reply 13): Thanks for the info. I only flew classic 737's and it was a while back. You are talking about the 737NG, right? I have Nope, I was talking about classic. Maybe it is a different software setup then. I used to fly -300/-500s and they had that feature. To be honest, I cannot really remember on the NG, but I guess it is available there as well. |
Quoting Flaps30 (Reply 11): OK, but what about SNA (John Wayne airport Orange County,CA). That seems to be an exception because the noise restrictions require departing aircraft to make a very steep initial climb. Can that be done on a lower thrust takeoff or is SNA one of the exceptions that require a full power takeoff? |
Quoting PGNCS (Reply 13): I have seen this most frequently on the MD-90 (this is an interesting difference from the MD-80; I wonder about the 717...) but it's possible on others as well. |
Quoting PhilSquares (Reply 17): If you have a EEC/FADEC engine you can certainly firewall them since you have protection on overboost, overspeed and overtemp. |
Quoting Mir (Reply 8): a wet runway also requires a full power takeoff. |
Quoting OffshoreAir (Reply 9): they only used full-power take-offs if the runway had a certain amount of rain water or snow on it. |
Quoting Mir (Reply 16): Quoting PGNCS (Reply 13): I have seen this most frequently on the MD-90 (this is an interesting difference from the MD-80; I wonder about the 717...) but it's possible on others as well. It can happen on the CRJ-200 as well. |
Quoting TK739ER (Reply 22): What is the reason for this? Maybe to cut the rolling time and get airborne asap because the runway surface is unstable?? |
Quoting TK739ER (Reply 22): What is the reason for this? Maybe to cut the rolling time and get airborne asap because the runway surface is unstable?? |
Quoting LU9092 (Reply 21): Back in December I rode on a UA A319 LGA to ORD. The weather was quite rainy that day in New York, and upon lining up on 31, the pilots held the plane with the brakes until the engines had reached (or, just about reached) takeoff thrust. |
Quoting Mir (Reply 16): full power takeoff (which is still not the max available power of the engines, since, as has been mentioned, the engines will be damaged if you firewall them |
Quoting LongHauler (Reply 26): Quite often at LGA, ATC will instruct you to "keep the thrust up, be ready for an immediate takeoff", as they are co-ordinating landings on the intersecting runway. Sometimes, depending on how high your thrust is when the takeoff clearance is received, it can be very dramatic. |