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More real life 747 flying - using reverse thrust in mid

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During my flight to London from Brisbane via Incheon, Korea - while descending on approach into Incheon, the aircraft emmitted a very loud engine roar , which to me sounded exactly like the engines had been put into some kind of reverse thrust . I have flown MANY times in 747-400s and have never experienced this before. At the time, the weather was very bad as a tropical typhoon was in the area - and , I don't know why, but I had a sensation that we were coming in quite fast. On arrival at Brisbane airport on my return trip, we also had poor weather with very poor vis, but the landing seemed much slower and smoother to me -- and no loud engine roar . Just the usual wind sounds from the speed brakes. I must admit I had different seating during the 2 flights - during the "noisy" one I was seated adjacent to the wing - while I was right down the back on the quiet one.Any real experienced 747 flyers out there who would like to comment?Thanks Barry

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Last year when I was going on holidays just at about Newfoundland (or thereabouts) the A330 I was in was turning to head down the eastern seaboard to Orlando during this, the right engine suddenly started to roar (turning left). I didn't know why but I a startled passenger asked a stewerdess. I tried to listen but couldn't(the engine roar remember :D ) but I did catch the word "normal". I know it wasn't a 747 nor am I a captain but I just thought I'd share because I am hoping for an explanation too :-):-wave

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>started to roar (turning left).Regarding the turning left, maybe they used differential thrust. I had this on a flight to LEPA.RegardsEtienne

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I believe that most aircraft thrust reverser systems require the "Weight on wheels" switch to be activated before the thrust reversers deploy. Unless the switch malfunctioned I doubt that the reversers deployed before the plane touched the runway. There was in incident some time back in a Lauda flight, I believe, that they did deploy in flight and the plane crashed. Most, if not all, thrust reverser systems have an independent locking mechanism to prevent inadvertent deployment. Maybe some 747 real world pilots will comment on this. Best reagards, Bob.

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I suspect that what you heard was forward thrust not reverse thrust. If the weather was bad, a microburst of windshear likely caused a drop in airspeed and they overcame it with thrust. I think spoiler deployment is about as far as they normally go in slowing you down in flight. I admit, however, that I know little about the 747. R-

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Normally using reverse thrust in mid air is highly prohibited.Did you flew with KAL? then it is easy possible. The dissobey every rule there is!Read and shiver:http://www.vision.net.au/~apaterson/aviati...orean_audit.htmAnd:http://www.vision.net.au/~apaterson/aviati...a_anchorage.htmJohan[A HREF=http://www.phoenix-simulation.co.uk]Phoenix Simulation Software[/A]Unofficial PSS website:www.people.zeelandnet.nl/johdMy help may not me much usefull, or usefull much..eh?http://people.zeelandnet.nl/johd/index2/Ar...s/Leg1/klm5.jpgTrue Blue! K L M!

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Also not a pilot and only an occasional flier, but could you see the wings at the time? I believe I've been on flights where the wind on the spoilers made a noticable sound when deployed for air-braking.Might've been the like the mad braking I usually do while crossing 10,000' in the sim. . . just a guess.Good question -- interested to know as well.Best,Greghttp://www3.sympatico.ca/gregory.moffatt/sig1.jpg

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I agree with all of the other posters here. You probably heard the spoilers deploying.

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Barry, Not a real 747 pilot but seems very unlikely that reverse thrust was applied in flight. My father is an aeronautical engineer who did some consulting work a few years back for an airlines/engine manufacturer because of a problem they had with thrust reversers inadvertantly deploying in flight. He told me that this would almost immediately jeopardize the safety of the flight by putting tremendous stress on the airframe and control surfaces when they reacted to the opposing thrust vectors on the airplane. And that is why it was critical that there was a fail-safe interlock engineered in so this could never happen in flight. Since the airplane was descending and seemed to be coming in faster than normal it seems almost for sure that what you heard and felt was speedbrake deployment, or possibly the autothrottle making large adjustments in thrust due to a windshear scenario. It would be good if a 747 or other jet driver chimed in, but I would expect a thrust reverser deployment in flight for any significnat period of time to result in the loss of the aircraft.chris (PHNL)

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That, and a possible accoustic problem. On some planes there's a system which attenuates the ambient noise by sending back some frequencies in opposition of phase, thus cancelling out part of the waves. There may be local oscillations. Also, our brain tunes out most of the noise most of the time but may on occasions revert to total alertness.This happens to me once in awhile.

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It definitely wasn't a reverse thrust engagement in flight since you are still here to write about it. I do believe that the last time I heard about a reverse thrust deployment in flight it was on a Discovery Channel program all about NTSB investigations after airline disasters!What you heard was most certainly the spoilers. If full flight spoilers are deployed (especially on the 747) you will get a very loud roar, shuttering and the ride in the cabin will get noticably bumpier as the spoilers deflects some of the laminar airflow over the wing...especially if you were sitting close to the wing area.FYI, reverse thurst cannot be engaged in flight without weight on the main gear :-)

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Thanks for the links Johan. The audit report is un-frigging believable. It is clear why FAA removed KAL's clearance to operate in and out of US airports (though I don't know where that stands today). I fly my AETI 742 Classic on FS2002 with more professionalism than the KAL flight deck crews, if the audit findings are all accurate. Intersection takeoffs at MTOW to save time, exceeding max cruise FL for current weight, not familiar with how to calculate takeoff thrust settings for weight, runway, temps, flight engineers questioning and sometimes over-ruling Capts decisions, not using current Jepp plates...wow, and the list goes on and on.I would never, ever, let a person I was close to fly on this airlines if this 3 year old audit report reflects their current standard of professionalism. Just read the NTSB report on the Guam crash...I talked to an FAA employee one time who had the pleasure of giving over 100 hours of deposition after this incident and what he said about the way the airplane was operated was unfortunately fairly consistent with what the audit report said. I hope they work through this, it must make the folks at Boeing shudder to see the way their products are being operated...

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Hello, Guys here are the facts..you can indeed open the thrust reversers on aircraft..well one aircraft... the DC-8..cos it had no spoilers to slow it down they could use the 2 and 3 engine sin reverse to slow down and drop FAST!!!! you can't do it on high bypass engines..STRICTLY-PROHIBITED..plus the landing gear ground switch needs to be engaged

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One of the only 767 crashes in the history of the fleet that was caused by mechanical failure was a Lauda Air in the 80s that deployed the left reverser in flight over the jungles of Thailand - the assymetrical thrust was so great it tore the plane up in midair... I'm pretty sure you didn't hear a reverser deploying!!!

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>Did you flew with KAL? then it is easy possible. The >dissobey every rule there is! >>Read and shiver: >http://www.vision.net.au/~apaterson/aviati...orean_audit.htm >>And: >http://www.vision.net.au/~apaterson/aviati...a_anchorage.htm In defence of KAL, these reports are both dated 1998!!!KAL has been "completely overhauled" since this time -- they now codeshare with a couple of US airlines and are back on the DOD list of recommended airlines.Frankly, I have a suspicion that KAL "might" now be a safer airline to travel with than some other airlines who have never (up until now) had any problems . There is nothing like a crash to focus the attention -- .Barry

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