Thrust reduction and acceleration altitude ?
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Thrust reduction and acceleration altitude ?
how come thrust reduction and acceleration occure at the same altitude ( simultaniously ) when thrust is directly proprotional to acceleration ( the more the thrust the more the acceleration ) .
doesnt make sense
acceleration must decrease if thrust is reduced
or perhaps im getting confused by the term ( thrust reduction and acceleration ).
doesnt make sense
acceleration must decrease if thrust is reduced
or perhaps im getting confused by the term ( thrust reduction and acceleration ).
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Thrust reduction is reducing the thrust from take off thrust to climb thrust. Generally happens between 1,000 to 1,500' agl depending on airline SOP.
The acceleration is increasing your speed from V2+10 to 20 (roughly 150-160 knots for most medium jets) to your initial climb speed, generally 250 knots. As you pass through the various bugged speeds for flap retraction you clean up the aircraft as well.
In order to actually increase the speed the aircraft has to be pitched down, slightly reducing the rate of climb but otherwise there would be no way of accelerating. In the A320 this is from 15-17 degrees nose up on the initial take off down to about 10 degrees nose up.
The acceleration is increasing your speed from V2+10 to 20 (roughly 150-160 knots for most medium jets) to your initial climb speed, generally 250 knots. As you pass through the various bugged speeds for flap retraction you clean up the aircraft as well.
In order to actually increase the speed the aircraft has to be pitched down, slightly reducing the rate of climb but otherwise there would be no way of accelerating. In the A320 this is from 15-17 degrees nose up on the initial take off down to about 10 degrees nose up.
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Thrust may or may not be reduced during the climb. Typically at 1,000' above field elevation (which can vary with the airport, the aircraft, and the operator, as well as the conditions or circumstance of flight (such as an engine failure, for example), climb thrust is introduced.
Climb thrust may be a power reduction, or it may be a power increase, depending on what was used for takeoff power. Sometimes we see it as a thrust reduction, but sometimes we have a thrust increase, too...sometimes followed again by a thrust reduction while passing through 10,000'.
We use two different types of departure profiles, both basically noise abatement departure profiles, when all engines are working. One involves making the climb thrust setting at a thousand feet, and accelerating to retract flaps also beginning at that altitude. The other departure involves climb thrust set at a thousand feet, with a climb continued at our V2 speed until 3,000' above field elevation. At that point our vertical speed is reduced to either five hundred feet per minute or a thousand feet per minute, and the aircraft is allowed to accelerate while gradually retracting flaps. We then accelerate to 250 knots, or the minimum airspeed for no flaps if it's higher than 250 knots (typically about 280 for us).
We then continue up to 10,000', where we reduce our rate of climb again in order to accelerate to our enroute climb airspeed. At this time, depending on the flight, we may call for a reduced climb thrust setting, or we may continue with the climb thrust we've already got set.
Climb thrust may be a power reduction, or it may be a power increase, depending on what was used for takeoff power. Sometimes we see it as a thrust reduction, but sometimes we have a thrust increase, too...sometimes followed again by a thrust reduction while passing through 10,000'.
We use two different types of departure profiles, both basically noise abatement departure profiles, when all engines are working. One involves making the climb thrust setting at a thousand feet, and accelerating to retract flaps also beginning at that altitude. The other departure involves climb thrust set at a thousand feet, with a climb continued at our V2 speed until 3,000' above field elevation. At that point our vertical speed is reduced to either five hundred feet per minute or a thousand feet per minute, and the aircraft is allowed to accelerate while gradually retracting flaps. We then accelerate to 250 knots, or the minimum airspeed for no flaps if it's higher than 250 knots (typically about 280 for us).
We then continue up to 10,000', where we reduce our rate of climb again in order to accelerate to our enroute climb airspeed. At this time, depending on the flight, we may call for a reduced climb thrust setting, or we may continue with the climb thrust we've already got set.
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Thrust reduction before 800'agl
Whats the minimum thrust reduction alt in a b737ng. Fmc does not accept entries below 800'. Is it allowed to switch from takeoff thrust to climb thrust before 800', lets say for an early level off (1000' or less)
Is it legally or as per procedures allowed?
Is it legally or as per procedures allowed?
