B747-100 engine problems on early versions
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Early -100's were also poor performers climb wise - on a hot day (for England) of 75-80F outbound from LHR they'd be slogging along below 10,000ft until they reached Manchester.
Regular cases reported of gliders from Booker and the Leicester area well above them
Regular cases reported of gliders from Booker and the Leicester area well above them
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Harry: I remember in, I think, 1972 when we lived in Abingdon feeling, hearing and then seeing what must have been about the first 747 I had ever seen climbing out heading west at a very low altitude.
Laurence
Laurence
His first words to us were 'London I'm not gonna make 4 thousand by Woodley'. I think he struggled through 3,600ft passing WOD.
My own experience was about 8 years later (early '78). Me and the first Mrs C were on our way to Mauritius; she worked for BA and had got us ID 90s. The route was Heathrow - Nairobi - Seychelles - Mauritius; I'd hoped for a VC10 but we got a 747; they used to 'alternate' the two types on that route.
After the turnround at Nairobi, one engine failed to re-start, so we were stuck there until a fresh engine could be flown in and fitted. (BA put us up in the 'Intercontinental Hotel' overnight).
24 hours later, all 4 started, we departed Nairobi and with Seychelles passengers already having gone on another flight, were to go direct to Mauritius. About an hour out, the 'new' engine started giving fire warning indications, so we returned to Nairobi. We stayed in the terminal because by this time, the next Mauritius bound 747 was imminent so we were all loaded on that to complete our journey some 48 hours late.
(Plus side for me was being allowed to stay on the flight deck for the landing at Plaisance!)
Old thread revived - and we've all leapt at it !
I wonder if you will be able to draw close parallels with the current situation on the recently introduced A320Neo, where Pratt & Whitney with the GTF engine have once again got into major reliability and failure issues with a new engine, which is having a considerable impact on the airlines who have ordered it. We are back to new aircraft stacked up at the factory with concrete blocks balancing where the engines should be.
Pratts, once the world leader, have in the meantime had a range of issues with the introduction of other new engines along the way as well, and have lost considerable market share.
Back to the old 747-100. Both TWA and Pan Am scheduled it nonstop daily on London to Los Angeles/San Francisco. BA refused to do so believing it to be beyond reliable 747 range at that time, no BA 747s to LAX until the first -200/RRs came along (I was on the first week's operation). The two US carriers departed Heathrow in the early afternoon, and were more than a little concern to ATC on warm summer days, especially if they were on easterlies going out over solid built-up areas. I wonder if the FE had any procedures they were standing by to implement if they got an engine failure at this stage. Pan Am were more than once referred to as a "Hedge Clipper" on what passed for a climbout, while TWA going off 9R (probably 10R then) were said to be "departing via the Piccadilly Line".
I wonder if you will be able to draw close parallels with the current situation on the recently introduced A320Neo, where Pratt & Whitney with the GTF engine have once again got into major reliability and failure issues with a new engine, which is having a considerable impact on the airlines who have ordered it. We are back to new aircraft stacked up at the factory with concrete blocks balancing where the engines should be.
Pratts, once the world leader, have in the meantime had a range of issues with the introduction of other new engines along the way as well, and have lost considerable market share.
Back to the old 747-100. Both TWA and Pan Am scheduled it nonstop daily on London to Los Angeles/San Francisco. BA refused to do so believing it to be beyond reliable 747 range at that time, no BA 747s to LAX until the first -200/RRs came along (I was on the first week's operation). The two US carriers departed Heathrow in the early afternoon, and were more than a little concern to ATC on warm summer days, especially if they were on easterlies going out over solid built-up areas. I wonder if the FE had any procedures they were standing by to implement if they got an engine failure at this stage. Pan Am were more than once referred to as a "Hedge Clipper" on what passed for a climbout, while TWA going off 9R (probably 10R then) were said to be "departing via the Piccadilly Line".
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Thanks all, please keep the stories coming, some smiles here in the office regarding the awful climb speed. We are keeping the story very much to the 747. With an hour less commercial breaks, time for tangents like the A320Neo just isn't there, interesting as it is.
[email protected] is the contact email. Thank you all for reading.
[email protected] is the contact email. Thank you all for reading.
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Shaft bow
I recall having to motor 2 engines at a time (only 2 hands!) during turnarounds, to cool the engines below 100C EGT, to prevent shaft bow on subsequent start up. Was a requirement to prolong engine life if I recall.
Also remember pulling multiple CBs in the cruise coming eastbound during the night, showing new FEs the tandem bleed system in action, in case they were ever needed to do a test in anger. Had no clue at time of how risky this regular practice was, risking a major engine malfunction if the bleeds went wrong!!
Also remember pulling multiple CBs in the cruise coming eastbound during the night, showing new FEs the tandem bleed system in action, in case they were ever needed to do a test in anger. Had no clue at time of how risky this regular practice was, risking a major engine malfunction if the bleeds went wrong!!
I did once see a spectacular surge on a TWA 747 walking home (ashford) early evening in the late 70s . LHR on easterlies aircraft headed for the west via Brecon had to make a long sweeping 180 degree turn while climbing up to the usual LHR 6000ft stop climb point. thaving lived next to LHR all my life abnormal engine sounds stuck in your mind-this one seemed like it was trying too hard and when it reached a point that would have been about due south of LHR it levelled off followed by a huge sheet of flame and black smoke like it had been hit by an AA shell and then just carried on -glad Iwasnt seated behind the wing. It was scary from the ground
re the Mauritius story BA -100 engine problems saw me and Mrs PB 'stranded ' in Seychelles from mid day Monday to Mid day Thursday . The plane arrived on time but had experienced engine problems on way down from Bahrain and although we were all boarded the captain eventually -after an hour passing said he wasn't happy departing SEZ with a dodgy engine with 1000 miles of ocean before any other and we would all have to get off.
Luckily our BnB room hadnt been released as the landlady had a policy of not releasing rooms until she saw the BA 74 depart. Nightmare for BA -spare engine shipped from Jo burg in Herc freighter , couldnt fly over several countries due apartheid, finally got to Sez in middle of huge thunderstorm and had to divert to Nairobi with out of hours crew who then had to recover and fly back to Sez where there were no proper facilities for doing engine changes .
God knows what if t cost BA as at the time Sez had small tourism sector and lots of pax were roomless with stories of male first class passengers having to doss on the beach for three nights (and BA wouldnt unload the bags).
We were lucky having three extra days at the airlines expense before heading on to Mauritius on what was my best ever biz trip itinerary , Seychelles,Mauritius and Nairobi over 24 days and because I ahd clocked up so much travelling over the past year my Company paid for Mrs PB to come too.(Silver lining and all thanks to P&W )
re the Mauritius story BA -100 engine problems saw me and Mrs PB 'stranded ' in Seychelles from mid day Monday to Mid day Thursday . The plane arrived on time but had experienced engine problems on way down from Bahrain and although we were all boarded the captain eventually -after an hour passing said he wasn't happy departing SEZ with a dodgy engine with 1000 miles of ocean before any other and we would all have to get off.
Luckily our BnB room hadnt been released as the landlady had a policy of not releasing rooms until she saw the BA 74 depart. Nightmare for BA -spare engine shipped from Jo burg in Herc freighter , couldnt fly over several countries due apartheid, finally got to Sez in middle of huge thunderstorm and had to divert to Nairobi with out of hours crew who then had to recover and fly back to Sez where there were no proper facilities for doing engine changes .
God knows what if t cost BA as at the time Sez had small tourism sector and lots of pax were roomless with stories of male first class passengers having to doss on the beach for three nights (and BA wouldnt unload the bags).
We were lucky having three extra days at the airlines expense before heading on to Mauritius on what was my best ever biz trip itinerary , Seychelles,Mauritius and Nairobi over 24 days and because I ahd clocked up so much travelling over the past year my Company paid for Mrs PB to come too.(Silver lining and all thanks to P&W )
TV Nick, if you need to understand water injection in a jet engine, you could start here B747-200 Water Injection Take Off - Airliners.net
Bear in mind that 1970, and the experience of the professionals then, was a lot closer to the propeller Atlantic airliner days of the late 1950s than 2018 is; this sort of performance is still better than what those old aircraft did - and these left London only with fuel to get to Shannon. At the end of the day aircraft performance has long been determined not by what the aircraft designer can come up with but by what the engine manufacturer can supply.
Sometimes I think of this nowadays when I see aircraft climbing out of London City's short runway at what looks like 45 degrees (yes, I know it's not). The world has moved on.
Back to the old 747-100. Both TWA and Pan Am scheduled it nonstop daily on London to Los Angeles/San Francisco. BA refused to do so believing it to be beyond reliable 747 range at that time, no BA 747s to LAX until the first -200/RRs came along (I was on the first week's operation). The two US carriers departed Heathrow in the early afternoon, and were more than a little concern to ATC on warm summer days, especially if they were on easterlies going out over solid built-up areas. I wonder if the FE had any procedures they were standing by to implement if they got an engine failure at this stage. Pan Am were more than once referred to as a "Hedge Clipper" on what passed for a climbout, while TWA going off 9R (probably 10R then) were said to be "departing via the Piccadilly Line".
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B747-100 turbine reversers
Thanks much for the photo of the turbine reverser blocker doors on what I assume was a -3A. I always wondered what they looked like.
I flew -100s and -200s in the early 2000's, we had several -100s from UAL and a couple other early line numbers from AA, DAL, etc.
All our 'classics' had -7A engines or better and in 3 years I never had a mechanical issue with one. Sometimes the -'Q' engines would rumble if pulled to idle above FL 300 so you'd wait til you were below that to reduce thrust fully.
We had 3 -70A powered birds and other than reverser issues (very different from ones on -7A/Q mills) I recall they ran about like the 'Q's did, i.e. well. We also flew a few -300s that had been converted to freighter configuration by Boeing/Wichita that were real 'Cadillacs', that had GE CF6-50E2s. The CF-6s burned slightly less fuel as didn't take as big as a performance 'hit' with anti-ice on.
There was a placard on several of our -100s above the engine instruments that read 'Turbine reversers permanently de-acivated, all 4 engines'.
Additionally, one could see a painted-over label next to the landing gear lever, in between the 'OFF' and 'DOWN' ones, that originally said 'WING'. On the very earliest airplanes apparently the wing gear could be lowered for use as a speed brake- perhaps for the comfort of transitioning DC-8 pilots.
I really enjoy the memories and recollections here, thanks. D.
I flew -100s and -200s in the early 2000's, we had several -100s from UAL and a couple other early line numbers from AA, DAL, etc.
All our 'classics' had -7A engines or better and in 3 years I never had a mechanical issue with one. Sometimes the -'Q' engines would rumble if pulled to idle above FL 300 so you'd wait til you were below that to reduce thrust fully.
We had 3 -70A powered birds and other than reverser issues (very different from ones on -7A/Q mills) I recall they ran about like the 'Q's did, i.e. well. We also flew a few -300s that had been converted to freighter configuration by Boeing/Wichita that were real 'Cadillacs', that had GE CF6-50E2s. The CF-6s burned slightly less fuel as didn't take as big as a performance 'hit' with anti-ice on.
There was a placard on several of our -100s above the engine instruments that read 'Turbine reversers permanently de-acivated, all 4 engines'.
Additionally, one could see a painted-over label next to the landing gear lever, in between the 'OFF' and 'DOWN' ones, that originally said 'WING'. On the very earliest airplanes apparently the wing gear could be lowered for use as a speed brake- perhaps for the comfort of transitioning DC-8 pilots.
I really enjoy the memories and recollections here, thanks. D.
Those wonderful turbine reversers on the -100 were operated by push-pull cables. A reverser drive unit was mounted on the engine gearbox. When reverse was selected it actually clutched into the engine gearbox and drove a ball-nut jackscrew. This pushed back four thick cables which were enclosed in sleeves. These were routed aft and spread to four points on the periphery of the reverser sleeve and shoved it aft. Linkages picked up the blocker doors.
Push-pull cables that are routed around a hot tailpipe tend to seize as did the tracks for the sleeve and the linkages. However the jackscrew on the engine gearbox did have the considerable power of a JT9D to drive it. On many occasions, troubleshooting a reverser failure the techies would open the lower cowling doors and be greeted with hunks of jackscrew casing and a shower of ball bearings. The jackscrew assembly had literally burst with the effort.
Locking the turbine reverser out required the sleeve be pushed forward. For this, the trusty beltloaders used for loose-baggage loading were a God-send. The thick rubber bumper at the top of the belt prevented damaging the sleeve and the engine on the unit gave the push. Much better than beating on it with heavy wooden balks although we did that too on occasion.
Eventually Boeing or maybe Pratt gave up on the turbine reverser. Then I went to Palmdale for L-1011 school and found Lockheed insisted that their "Hot Stream Spoiler" was necessary. They used two jackscrews back on the tailpipe to push the sleeve back and they were driven by very high rev flex shafts. The flex shafts and jackscrews did not like being in the company of a hot tailpipe either. They often failed and eventually, Lockheed gave up on them too. Never had anything to do with the DC-10 and I wonder if they went down the same path?
Push-pull cables that are routed around a hot tailpipe tend to seize as did the tracks for the sleeve and the linkages. However the jackscrew on the engine gearbox did have the considerable power of a JT9D to drive it. On many occasions, troubleshooting a reverser failure the techies would open the lower cowling doors and be greeted with hunks of jackscrew casing and a shower of ball bearings. The jackscrew assembly had literally burst with the effort.
Locking the turbine reverser out required the sleeve be pushed forward. For this, the trusty beltloaders used for loose-baggage loading were a God-send. The thick rubber bumper at the top of the belt prevented damaging the sleeve and the engine on the unit gave the push. Much better than beating on it with heavy wooden balks although we did that too on occasion.
Eventually Boeing or maybe Pratt gave up on the turbine reverser. Then I went to Palmdale for L-1011 school and found Lockheed insisted that their "Hot Stream Spoiler" was necessary. They used two jackscrews back on the tailpipe to push the sleeve back and they were driven by very high rev flex shafts. The flex shafts and jackscrews did not like being in the company of a hot tailpipe either. They often failed and eventually, Lockheed gave up on them too. Never had anything to do with the DC-10 and I wonder if they went down the same path?
Last edited by tonytales; 18th Apr 2018 at 07:57. Reason: Completing a sentence
The maiden commercial flight in January 1970, Pan Am from JFK to London (already delayed a month), got this on startup and they had to transfer to a backup aircraft which meant they were 4 hours late at London.
It was about this time that a New York bound one lost an engine shortly after it departed Heathrow. I don't think it went near Abingdon but apparently it was only able to maintain about 1200ft by dumping fuel, turning near Reading and passing almost overhead Farnborough to get back to Heathrow.
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tonytales @51, thanks for that very interesting information re turbine reversers...I remember seeing early DC-10s with some sort of vane at the aft end of the hot section exhaust that looked much like those on the L-1011; hard to imagine they'd have had much better results than P&W after your description of all that had to work well in that sort of temperature environment! Good intentions but in the end not worth the $$ or mechanical headaches it seems.
Yes the -100 series airplanes even with -7A mills had rather stately climb profiles. I did enjoy flying them though.
Yes the -100 series airplanes even with -7A mills had rather stately climb profiles. I did enjoy flying them though.
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Thanks for that story chevvron. My memory is that the one over Abingdon was PanAm.
My first passenger flight in a 747-100 was with TWA in 1972, Heathrow to O'Hare, and I was amazed at the time we stayed on the ground between starting the roll and getting airborne.
Laurence
My first passenger flight in a 747-100 was with TWA in 1972, Heathrow to O'Hare, and I was amazed at the time we stayed on the ground between starting the roll and getting airborne.
Laurence
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I was in ATC at Lyneham 1970-1972. Lyneham was directly under the Airway Green 1 and we would regularly get requests from London for 5000ft through our overhead due to slow climbing 747's!
Last edited by JRFD; 26th Apr 2018 at 11:19. Reason: tense
