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Based on my experience with jet transport aircraft, thrust reverser levers can only be engaged after reducing the throttle to idle. Do any jet-powered aircraft exist that can engage the levers at power settings above idle?

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  • $\begingroup$ Define thrust reverser. $\endgroup$
    – Jim
    Commented Jan 21, 2023 at 6:37
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    $\begingroup$ @Jim Thrust reverser is a mechanism that changes the direction of the thrust vector by approximately 180°, while preserving as much of it's magnitude as possible. $\endgroup$ Commented Jan 21, 2023 at 23:59
  • $\begingroup$ More like 100-120 deg. The deceleration you get is fairly modest, and is not even included in stopping distance performance data. Basically considered a bonus. Almost all of your stopping power is brakes. Cascade style reversers are the worst. $\endgroup$
    – John K
    Commented Jan 22, 2023 at 3:27
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    $\begingroup$ @AdityaSharma - Yes. I was probing to see whether their definition covered things like thrust vectoring. $\endgroup$
    – Jim
    Commented Jan 22, 2023 at 20:29
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    $\begingroup$ Are you only interested in "as delivered" or also in "after modification"? $\endgroup$
    – BowlOfRed
    Commented Feb 3, 2023 at 0:23

2 Answers 2

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There are no commercial aviation aircraft that are made this way. There are physical locks inside the throttle levers that make it impossible to raise the reverse thrust lever if the throttle lever is forward of idle.

Now, you say "any"...that's pretty broad. I'm not going to say there's never been some obscure, weird airplane no one's ever heard of that might have been designed like you're saying, but it's hard to imagine why any manufacturer, civilian or military, would think this would be a good idea.

Edit:

  1. The source is my own experience. I am personally familiar with a wide variety of commercial jet aircraft spanning several decades of flying them, and no manufacturer designs TRs like this. Just the opposite: just having a TR become unlocked when it isn't supposed to is a problem that requires immediate attention. If the TR actually deploys, the engine will be commanded to idle by the EEC; in some older designs before EECs, the throttle would actually slam back to idle.

  2. This question was already answered here almost 9 years ago anyway.

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  • $\begingroup$ Nice find on the duplicate question! $\endgroup$
    – Ralph J
    Commented Feb 4, 2023 at 21:16
  • $\begingroup$ "some obscure, weird airplane" -- The heavily modified biz jet used by astronauts to practice landing the space shuttle needed a lot of drag in order to be appropriately brick-lick. I think it had the ability to deploy thrust reversers in flight. But that is certainly an obscure, weird airplane. $\endgroup$ Commented Mar 6, 2023 at 16:29
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The C-17's reversers can be used to back up on the ground. The pilot must throttle-up to do this.

They can also be deployed in flight during a tactical descent. I believe the throttles are usually kept at idle during this maneuver.

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    $\begingroup$ DC-8s (if any are still flying) can use thrust reversers (on 2 of the engines I believe) in the air. $\endgroup$
    – user22445
    Commented Jan 22, 2023 at 0:01
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    $\begingroup$ @757toga do they need to spool down to flight idle before engaging the thrust reverser mechanism? $\endgroup$ Commented Jan 22, 2023 at 0:02
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    $\begingroup$ @AdityaSharma It is my understanding that the thrust levers have to be at flight idle. I've never flown a DC 8 so I don't know if there is a published spool down criteria before engaging the reversers. $\endgroup$
    – user22445
    Commented Jan 22, 2023 at 4:28
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    $\begingroup$ @757toga sure, thanks $\endgroup$ Commented Jan 22, 2023 at 5:43
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    $\begingroup$ This doesn't answer the question! There are many aircraft that can use reversers to back up on the ground as well as in the air. However, in all of those I'm familiar with, you first have to retard the thrust levers to idle, then engage the reversers, and then you can add thrust again (usually with the reverse levers). $\endgroup$
    – Bianfable
    Commented Jan 22, 2023 at 11:32

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