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What does flex thrust mean?
Flex thrust essentially takes advantage of the spread between the actual weight at the actual temperature and whatever the maximum temperature for that weight would be. Assume, for example, that we are preparing for takeoff from an airport with an outside air temperature (OAT) of 10 degrees C.
What is Flex thrust takeoff?
An assumed temperature takeoff (also known as “flex” on Airbus/Fokker aircraft) is where the engine thrust is reduced to match the performance on a higher-temperature day, up to either the maximum thrust reduction allowed or the maximum assumed temperature that meets takeoff distance requirements.
What is flex in Airbus?
From Wikipedia, the free encyclopedia. Flex temp is a technique used to produce cost savings through increased engine life and reduced overhaul and fuel costs for airliners by allowing them to take-off at less than rated thrust. For Airbus and Fokker aircraft the technique is known as flex temp or just flex.
What is flat rated thrust?
A flat-rated engine’s thrust remains practically constant during an increase in altitude up to a certain limit. A method of referring to the engine-rated thrust or engine-rated shaft horse-power (SHP) that is guaranteed to be available up to a specific ambient temperature. Also called a re-rated engine.
What is the difference between Flex and TOGA?
“FLEX” is the standard takeoff thrust setting used on Airbus aircraft, unless departing a contaminated (wet / icy) runway or if performance constraints (short runway or hot and high) exist, in which case TOGA (full thrust) is used.
Can a bump engine be used for Flex thrust?
With a engine which is more derated you can keep your max. climb thrust up to higher altitudes, before your thrust decreases due to lower air-pressue. Now on the A333 we can even derate the engines through the FMS in case of low take-off weights. Never heard of bump thrust.
What’s the difference between climb thrust and flex thrust?
And for the climb there are 3 as well: Full climb thrust (CLB), reduced one (CLB-1) and reduced two (CLB-2). The FMS selects them automatically according to the FLEX temperature. The higher the FLEX temperature the higher the climb thrust reduction as well. On the 737 you can do it for take off as well. 20k, 18k, 16k.
How is Flex used to reduce take off thrust?
Flex: you “tell” the engine that it is a lot hotter than it actually is (FLEX temperature) and the engine cannot give as much thrust in high temperature conditions than in low temperature conditions. So the engine reduces the N1 and there you go This method is used to reduce take-off thrust and thus reducing EGT at take-off.
What’s the difference between LR and flex thrust?
They are available with different thrust ratings. The 145EP is lower than the LR for instance. Flex: you “tell” the engine that it is a lot hotter than it actually is (FLEX temperature) and the engine cannot give as much thrust in high temperature conditions than in low temperature conditions.