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C-17 tactical descent

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C-17 tactical descent

Old 15th May 2017, 09:34
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C-17 tactical descent

A fairly interesting video for those of us used to more sedate descents.
https://youtu.be/khBioU1qFVY
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Old 15th May 2017, 14:39
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Hope Ryanair don't try that next time I fly into La Rochelle with them
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Old 15th May 2017, 16:18
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I took some cadets for trip with 99 Sqn last year. The high rate descent was very impressive (especially for such a big aircraft) - all 4 engines into reverse thrust at FL190, RoD 20,000fpm. I even came off the floor as the aircraft was pitched nose down.
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Old 15th May 2017, 22:53
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I guess you had to be there............
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Old 16th May 2017, 09:45
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Further to "2" above, sometimes the arrival on terra firma feels like they have.......
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Old 16th May 2017, 15:01
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with reference to #2 above, the old saying about a landing being a crash you walk away from suddenly seemed very true as the Irish SLF 737 did its best to leave its main gear below sea level at MLA.
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Old 16th May 2017, 22:27
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all 4 engines into reverse thrust at FL190
Reverse thrust in flight??
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Old 16th May 2017, 22:36
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Reverse thrust in flight??


HS Trident, high RoD, centre engine in reverse...
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Old 17th May 2017, 05:49
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Reverse thrust in flight probably pioneered by the DC-8. Remember a rather rapid let down between thunderstorms at Houston January 1967 courtesy of Delta DC-8 with reverse deployed.
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Old 17th May 2017, 07:13
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Not to mention Concorde, inflight reverse was authorized, no speed brakes on the
production aircraft.
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Old 17th May 2017, 12:08
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Originally Posted by MightyGem View Post
Reverse thrust in flight??
Yes, all four engines can go into reverse thrust in flight. The C-17 also has speed brakes. In speed brake mode the flaps extend to dramatically increase drag, and the spoilers deploy to cancel out the increase in lift caused by the flaps and also further increase drag. This makes possible a tactical descent well in excess of 20,000 ft/min. The idea being to arrive directly over the destination airfield in a combat zone at high altitude and then very rapidly spiral down and land before an enemy outside the airport can drop mortars or other weapons on the runway. It works very well.

And incidentally, besides in flight reverse, the reversers are safe and effective at negative airspeed. Meaning the C-17 can back up on the ground under its own power at max weight, up a 2% slope, into a tail wind. On almost all aircraft you don't want to use the reversers below about 50 knots because of "re-ingestion," where the engines re-ingest exhaust air which can cause severe compressor stalls.
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Old 23rd Aug 2017, 17:36
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Don't think mentioning cadets, reverse thrust and 20,000 RoD in same sentence is to help cadets getting flying if someone from 2FTS read this 🤐
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Old 23rd Aug 2017, 22:00
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Originally Posted by MightyGem View Post
Reverse thrust in flight??
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Old 23rd Aug 2017, 23:20
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I got religion one night in a DC-8 headed towards Oz from Vietnam....when the Pilots needed to get down quick....with some silly explanation about a late clearance from ATC.

I am thinking they simply screwed up and were late starting down....which they made up for in a very dramatic fashion.
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Old 27th Aug 2017, 23:34
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Yes, all four engines can go into reverse thrust in flight.
Thanks for that.
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