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Old 7th Jan 2018, 00:14
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Judd
 
Join Date: Oct 2007
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One thing is for sure. That is you need to read the 737FCTM instructions carefully when it comes to reducing the reverse thrust application approaching taxi speed.

The FCTM states by 60 knots start reducing to reverse idle so that by taxi speed you are at reverse idle which is around 22% N1. Some pilots misinterpret this to mean at 60 knots cancel reverse completely. Nothing could be further from the truth.

Cancelling reverse at 60 knots will cause the aircraft to increase speed momentarily because the engine RPM is still relatively high as it winds down towards 22% N!. In the simulator, prompt cancellation of full reverse (nominally around 88% N1) at 60 knots reveals the reverser lights extinguish by the time the N1 is passing 60% N1 on the way down to forward idle of 22% N1. 60% N1 forward thrust (however momentary) is a lot of power which is the last thing you need if runway length is limited.
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