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Post by aerofoto - HJG Admin on Jul 8, 2011 5:37:10 GMT
That sounds like "our accident" (AIR NEW ZEALAND) at AKL INTL during July 1966 (DC8-52 ZK-NZB) .... but .... which was brought about by a completely different circumstance .... as per the following article which I wrote about it .... It came to light .... after the AIR NEW ZEALAND crash .... that UNITED AIR LINES had a similar experience with the DC8-50 thrust lever system .... as had also the same AIR NEW ZEALAND check-captain supervising a previous training flight too (it's since been reasomed that he believed that he, himself, had caused the event, rather than it being caused by a flaw within the thrust lever system onm these aircraft) some months prior to the AIR NEW ZEALAND crash .... but fortunately .... on both previous occasions these aircraft had more than sufficient altitude/time to recover from the effects of the generated asymetric thrust condition. Unfortunately too .... these events occurred during those days prior to "share your experience" apparently becomming standard/routine/mandatory throughout the airline industry .... or so I've been told ! Mark C AKL/NZ
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Post by spey511 on Jul 8, 2011 8:31:55 GMT
July 1970, Air Canada DC-8-63 CF-TIW struck the runway heavily after the first officer had inadvertently activated the ground spoilers some 60 feet above ground, causing the number 4 engine and pylon to separate from the wing and fall on the runway allowing fuel to escape and subsequently ignite. The aircraft rose back into the air and climbed to an altitude of 3100 feet as fire and smoke were seen trailing behind the aircraft intermittently. The crew wanted to circle for an emergency landing on runway 32, this was not possible because of debris on the runway, so the controller suggested a landing on runway 23. About two and a half minutes after the initial touchdown an explosion occurred in the right wing outboard of the number 4 engine location causing parts of the outer wing structure to fall free to the ground. Six seconds later a second explosion occurred in the vicinity of number 3 engine and the engine with its pylon ripped free of the wing and fell to the ground in flames. Six and one half seconds later a third explosion occurred which caused the loss of a large section of the right wing. The airplane then went into a violent manoeuvre, lost height rapidly and struck the ground at a high velocity, about 220 knots in a left wing high and nose low attitude killing all 109 persons on board.
June 1973, Loftleidir DC-8-61 (N8960T) made a short, hard landing after the first officer had inadvertently activated the ground spoilers during the final phase of the landing approach. The aircraft was damaged extensively when it hit the runway and injured 38 persons.
Responding to recommendations, the FAA then issued an airworthiness directive regarding the installation of a spoiler handle lockout.
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Post by aerofoto - HJG Admin on Jul 8, 2011 22:20:49 GMT
What Benoit comments regarding (above) hilites another unique detail in regard to DC8's .... in that their wing spoilers must not/cannot ever be deployed inflight. The wing spoilers on DC8's are for ground deployment "ONLY" Take an HJG DC8 up to altitude. Then pull-on the wing spoilers .... inflight. And just see/note what then happens ;D Whilst DC8 SHIP ONE (1959) was undergoing ceryification testing the test crew unexpectedly discovered a flaw in the aircraft spoiler system. Whilst departing from KSFO (during a touch'n'go I think it was) .... the aircraft was accelerating through the RWY intersection where there was a minor/natural rise .... which was "just enough" to apparently cause the nose gear to comprerss as the aircraft traversed that section of RWY with sufficient momentum as to cause the aircrafts wing spoilers to extend during the T/O roll .... and which resulted in a modification to the aircrafts spoiler system at that stage prior to the types entry to service. Mark C AKL/NZ
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Post by skyking on Jul 9, 2011 0:37:43 GMT
FWIW, I quote from our -71 Manual.
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THRUST REVERSERS -
Ground - Backing the airplane with thrust reversers IS NOT ATHORIZED. - Do not use thrust settings beyond reverse idle detent on the outboard engines until the nose wheel is on the ground. - Maximum reverse thrust may be used down to 60 knots. - Except in an emergency: - Do not use reverse thrust while taxiing. - Do not use reverse thrust above idle when below 60 knots. - Do not use thrust settings which produce engine stalls or "popping".
IN FLIGHT - Wing flaps must be fully retracted when using reverse thrust. - Inflight reversing of No. 1 and No. 4 engines is not authorized. - Do not use reversers below 190 knots. - Maximum reverse thrust may be used on inboard engines. - Do not stow reversers above 300 knots.
-------------------------------
Then there's some restrictions with the reversers inop.
Sorry I couldn't get the formatting to come out better.
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Post by skyking on Jul 9, 2011 0:48:02 GMT
I might add that I NEVER used inflight reverse except on training flights or in the sim. If they were to be used, a PA announcment was to be made. They weren't too bad on all BUT the -71s. With the bigger engines, they shook a little more. I feel it was just poor planning if anyone ever had to use them.
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Post by Tony Madge - HJG on Jul 9, 2011 7:26:33 GMT
I did not realise that airliners used reverse thrust in flight I know a few years back a Lauda Air 767 crashed due to uncommanded reverse thrusters deploying killing all on baord. I would guess that it would feel like the brakes going on once they were deployed on the DC8 I recall a flight on a BEA 1-11 on route to Jersey C.I. once we took a route over Wales which was not the normal route due to air traffic and as the pilot began the decent he came over the PA to announce that we were going rather faster than we should and not to be concerned to see the spoilers being deployed as we needed to slow down! I know the Comet 4 had a restriction where spoilers could NOT be deployed in flight without dire results.
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Post by skyking on Jul 9, 2011 12:13:41 GMT
The DC-8 is the only aircraft I know of that is certified for in-flight reverse.
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Post by christrott on Jul 9, 2011 16:03:36 GMT
The Trident was certified for limited reverse deployment on short final and was used to get into a few runways that were short during wet conditions. I'll see if I can dig up the post from Peter Mackay over at the CBFS forum on it if Garry doesn't beat me to it.
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Post by jonm on Jul 9, 2011 22:38:32 GMT
I'm not sure I'd want to be the pilot testing the safety and effectiveness of using reverse thrust in-flight. Based on history sounds a bit like Russian roulette.
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Post by christrott on Jul 11, 2011 2:09:42 GMT
Nothing inherently wrong with it as long as you make sure the plane's designed to handle it. It really doesn't put much more stress on the airframe or the pylons to do it in the air than it does when doing a high performance reverse on landing or when powerbacking the aircraft (like is done with the C-17 and C-5).
BTW, I just remember that both the C-17 and C-5 are certified for inflight thrust reverse of the CORE FLOW only. I believe that some of the turbofan 707's had the same capability although I don't know if it was ever used.
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Post by aerofoto - HJG Admin on Jul 16, 2011 6:08:37 GMT
Peter LIDDELL has kindly supplied with yet more great looking EASTERN AIR LINES DC8-20 classics .... which I've added to the above presentation. These latest additions include all of the following .... - EASTERN AIR LINES DC8-21 N8602 (1960) with the full/classic "FLY EASTERN'S GOLDEN FALCON JET" ledgend and double flag (delivery scheme). - EASTERN AIR LINES DC8-21 N8607 (1962) with the later shortened "FLY EASTERN AIRLINES" ledgend, double flag, and white tail. - EASTERN AIR LINES DC8-21 N8615 (1962) with the shortened "FLY EASTERN AIRLINES" ledgend, single flag, and striped tail. - EASTERN AIR LINES DC8-21 N8606 (1966) with the original Hockey Stick livery featuring "EASTERN" titles on the tail. - EASTERN AIR LINES DC8-21 N8609 (1968) with the classic Hockey Stick livery. Many thanks for these B----E----A----U----T----I----E----S Peter ! And .... I understand Peter's nowhere near "done" yet folks .... SO .... watch this space for more .... great EASTERN AIR LINES classics from those good old days of US civil aviation ! Mark C AKL/NZ
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Post by Peter Liddell - HJG Admin on Jul 16, 2011 16:16:47 GMT
No, i've still got lots more lovelies in the paint hangar. Couple little tidbits on the new previews: N8607 was unique with the white topped tail. Sadly it crashed into Lake Ponchartrain in 1964. N8606 with the tail titles was one of 2 designs considered for the early Hockey Stick scheme, the other did show up on at least one DC-8 but I don't have any references for it. It had the "blue circle" logo on the tail and the cheatline going straight off the fuselage. As Mark said, watch this space!
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Post by aerofoto - HJG Admin on Jul 17, 2011 0:29:35 GMT
If it's of any interest/help to you Peter .... I do have a photo of that particular aircraft.
It was DC8-21 "N8160".
My image is dated 1964 .... but in reality .... I suspect it might be a little later than that.
Mark C AKL/NZ
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Post by Peter Liddell - HJG Admin on Jul 17, 2011 1:02:24 GMT
Mark if you'd be willing to send me the photo I'd be happy to paint it up
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Post by aerofoto - HJG Admin on Jul 17, 2011 1:30:17 GMT
"SURE THING" Peter .... just give me a few days to get organized ! Mark C AKL/NZ
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