Reduced Versus Full Takeoff Thrust
Joined: Jun 2001
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From: Boldly going where no split infinitive has gone before..
A guess, but 85-90 percent of all takeoffs (EK 777).
Sometimes it's not much (say a 52 deg ASS TEMP on a 38 deg day), but TOGA thrust is usually only used on very heavy takeoffs (say DXB-LAX with a limiting load) or if there is a contaminated runway, or suspected windshear.
Sometimes it's not much (say a 52 deg ASS TEMP on a 38 deg day), but TOGA thrust is usually only used on very heavy takeoffs (say DXB-LAX with a limiting load) or if there is a contaminated runway, or suspected windshear.
Joined: Oct 2010
Posts: 430
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From: Germany
well... on the current turboprops reduced takeoffs are not approved, but on my previous bae146 time we used reduced takeoffs whenever possible, lets say 90% of the flights.
we had to perform one full thrust take off every 7 days on each aircraft for a performance check .
we had to perform one full thrust take off every 7 days on each aircraft for a performance check .
Joined: Dec 2000
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From: on the golf course (Covid permitting)
BA B747-400,
Note: retired 2 years ago
Reduced thrust almost every time.
The exceptions being places like Mexico City and Jo'berg, where fuel requirements and payload combined with the density altitude often required virtually full thrust (JNB maybe 1.72 EPR vs 1.74 max, but near as the same thing).
Some places (like MEX, JNB, GRU) also use an Aft C of G optimisation technique to maximise RTOW and gain payload.
Sometimes using a short runway eg Chicago, Cape Town or to avoid a delay also, but even on a long flight ex Singapore, you would normally derate somewhat to reduce from full thrust allowing 20,000+ hours on wing commonly for the engines.
Note: retired 2 years ago
Reduced thrust almost every time.
The exceptions being places like Mexico City and Jo'berg, where fuel requirements and payload combined with the density altitude often required virtually full thrust (JNB maybe 1.72 EPR vs 1.74 max, but near as the same thing).
Some places (like MEX, JNB, GRU) also use an Aft C of G optimisation technique to maximise RTOW and gain payload.
Sometimes using a short runway eg Chicago, Cape Town or to avoid a delay also, but even on a long flight ex Singapore, you would normally derate somewhat to reduce from full thrust allowing 20,000+ hours on wing commonly for the engines.
Joined: Dec 2003
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From: PORTUGAL
Flying A319/20/21, every take-off done in rwys in excess of 7000' are done in Flex Temperature (reduced thrust). Except if windshear reported/expected.
Regards.
Regards.
Last edited by C212-100; 27th October 2011 at 23:07.
Joined: Feb 2009
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From: Austria
Dash 8: in summer about 80%. The few times a non-reduced T/O is needed are usually due to limiting runways, which are not uncommon in my conpany.
In winter on the other hand, approx. 60-70% of takeoffs will likely be full power: icing conditions or deicing fluid present on the aircraft are among the items excluding a reduction in T/O power.
In winter on the other hand, approx. 60-70% of takeoffs will likely be full power: icing conditions or deicing fluid present on the aircraft are among the items excluding a reduction in T/O power.
Joined: Dec 2002
Aviation Qualifications: ATP+Mil
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From: Where the Quaboag River flows, USA
USAF: heavy airlift, probably 70% of the take-offs were reduced, but the C-5 would require full thrust at many weights.
Corporate: about 50% or so in the Global, could be more if we put emphasis on using reduced power.
Reduced is the way to go probably 90'% or more: better margins, less wear, less likely to have a failure.
GF
Corporate: about 50% or so in the Global, could be more if we put emphasis on using reduced power.
Reduced is the way to go probably 90'% or more: better margins, less wear, less likely to have a failure.
GF
Joined: Jul 2007
Aviation Qualifications: ATPL
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From: Germany
We do it nearly all the time and since the advent of laptop performance calculations it can look pretty strange. I remember the tower asking us if we had had an engine failure the first time we used the laptop assumed temperature on a 4000 meter runway. Low visibility is another time we do not use it.
Joined: May 2003
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From: Europe
Assumed temp. is used in most cases. Even in outside 36-40 Degrees Cent. we can still use 44 or 46 Degrees to cut the peak.
With the monitoring ability of Engine datas and maintenance from today the "standing time" of engines is increased significant the last 20 Years.
Whenever needed due to RWY, equipment failure or anything else: Full Thrust is used. Also once in 30 days was a proceedure I remember from a prevoius Employer.
Fly safe and land happy
NG
With the monitoring ability of Engine datas and maintenance from today the "standing time" of engines is increased significant the last 20 Years.
Whenever needed due to RWY, equipment failure or anything else: Full Thrust is used. Also once in 30 days was a proceedure I remember from a prevoius Employer.
Fly safe and land happy
NG
Joined: Oct 2011
Posts: 30
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From: Oregon
'Engine Guarantees'....gotta love that term. Was that coined by the blind mechanic with the blurry boroscope who's job it is to keep the engines up in the air? Tell me Mutt...how does he check if a there is bearing wear? Is there a special radar machine for that?