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rivermivida

Why do i need to use reverse thrust....?

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Autobrakes are designed to provide a certain rate of deceleration. The specific rate depends on the level of autobrake. These brakes must be certified without the use of revese thrust to stop the aircraft in the prescribed distance based on the charts. So, you DO NOT need reverse thrust. However, using reverse thrust will contribute some work to this set rate of deceleration. With a constant level of braking, this means you would stop sooner. However, the autobrakes detect this increased rate of deceleration and ease off the wheel brakes so that the combination of the wheel brakes plus the reverse thrust equals the same rate of deceleration that you would get with just autobrakes at any given level. The end result is less brake wear and therefore less money the airline spends replacing brake pads. Of course, the story isn't that simple. Reverse thrust places a stress on engines as well...and engine life cycles aren't cheap. Many airlines have SOP's that basically say they would rather replace brake pads frequently than replace engines at any rate. The result is that many airlines land with "idle reverse thrust" which deploys the reverse thrust, but does not spool up the engine beyond idle. The result is virtually no increased engine wear, but a small amount of reverse thrust that decreases brake wear. Eric Szczesniak

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Autobrakes are designed to provide a certain rate of deceleration. The specific rate depends on the level of autobrake. These brakes must be certified without the use of revese thrust to stop the aircraft in the prescribed distance based on the charts. So, you DO NOT need reverse thrust. However, using reverse thrust will contribute some work to this set rate of deceleration. With a constant level of braking, this means you would stop sooner. However, the autobrakes detect this increased rate of deceleration and ease off the wheel brakes so that the combination of the wheel brakes plus the reverse thrust equals the same rate of deceleration that you would get with just autobrakes at any given level. The end result is less brake wear and therefore less money the airline spends replacing brake pads. Of course, the story isn't that simple. Reverse thrust places a stress on engines as well...and engine life cycles aren't cheap. Many airlines have SOP's that basically say they would rather replace brake pads frequently than replace engines at any rate. The result is that many airlines land with "idle reverse thrust" which deploys the reverse thrust, but does not spool up the engine beyond idle. The result is virtually no increased engine wear, but a small amount of reverse thrust that decreases brake wear. Eric Szczesniak
Great! But...how should i aplicatte this in the simulator..?

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Set autobrakes 2 or 3, verify spoilers are armed. When you reach 30 feet above the runway, put the throttles on idle. Upon touchdown, do not press F2 or engage reverse thrust. Autobrakes will kick in and spoilers will automatically deploy. At 60 knots press and hold the period key (brake key) for 1-2 seconds TWICE. This will disengage autobrakes and you will have manual braking.

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Even if you do not plan on needing a lot of reverse, you should still unlock them when you touch down. That way, you have them ready to go if things get interesting.

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You also need to use Reverse thrust when brake cooling for turnarounds is an issue. If you use autobrake 3 with no reverse on an average afternoon at madrid (LEMD), you will need around 50 minutes brake cooling before you can depart again. Use second detent reverse thrust and brake cooling ceases to be a consideration. When landing on slippery/ contaminated runways, use reverse thrust up to max reverse until you slow to taxi speed or indeed to stop the aircraft if you lose traction on the wheels. if you don't deploy them, and then need them in an emergency, you can count to 12 before you begin to see any effect. T

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Great! But...how should i aplicatte this in the simulator..?
Hmm simulator yes.. Why use either, why not just stall and crash into ground.

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