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Why Did TWA Have So Many Turbojet 707s?  
User currently offlineJackbr From Australia, joined Dec 2009, 663 posts, RR: 0
Posted (3 years 2 weeks 4 days 20 hours ago) and read 11261 times:

TWA had.a very large turbojet 707 fleet well after the 1973 fuel crisis. They even bought Continentals 707-124s in 1967. I know they also had a sizeable fleet of turbofan 707B/Cs but they never converted any of their 707-120s, and continued to fly the 707-331 on domestic flights right up until 1978/79

How did they make these aircraft work for them for
so long while the other main US airlines sold theirs off much sooner?

18 replies: All unread, jump to last
 
User currently offlineViscount724 From Switzerland, joined Oct 2006, 24080 posts, RR: 22
Reply 1, posted (3 years 2 weeks 4 days 18 hours ago) and read 11009 times:

The turbojet -331 couldn't be converted to turbofans, at least no standard 707-320st ever were as far as I know.

Re the -131s, I expect TWA decided that the benefits of converting them to -131Bs didn't offset the costs, especially when fuel prices were very low and TWA's financial situation was generally weak. The turbojet -131s were disposed of around 1970-71, well before the first fuel crisis. Later TW -131 deliveries (as late as 1967) were all -131Bs.


User currently offlineMEA-707 From Netherlands, joined Nov 1999, 4265 posts, RR: 34
Reply 2, posted (3 years 2 weeks 4 days 17 hours ago) and read 10938 times:

The 707-331 nonfans were mainly used on domestic and shorter international services, at least I never saw many pictures of them in Europe or the mid east after 1970.
It's the same reason why some airlines (NW) hold on longer to DC-9s and DC-10s then others, or why MEA hold on longer to 707s, costs and opportunity costs of doing something else.

Most of the flights between 1974 and 1979 on which TWA used the 707-331 nonfans could indeed be done by 727-200s. But because TWA wasn't doing well economically they probably couldn't finance more 727s. For instance (all examples with fictivious rates) maybe banks would ask 8% interest at United or American to finance their 727 order while they would ask TWA 13% to cover the increased risks of bankruptcy, or they would refuse any loan at all. There weren't many lessors like GECAS and ILFC yet at the time.
Also the 707-331 nonfans probably had low utility rates. TWA probably planned in their 727-200s and Tristars, back then their most efficient domestic aircraft, to the fullest and only use the nonfans at peak hours. Also in that case it's cheaper to have old but fuelthirsty aircraft standby , instead of buying expensive 727s which don't have much to do on tuesdays and early afternoons.
Another reason which I can think of is that Pan Am just happened to sell their 707-321 nonfans around 1970 just before the fuel crisis, because they bought relatively more 747s and later 707-321Bs at the time. But by the time the fuel crisis broke out and TWA would have liked to sell them and use the money for efficient 727-200s in 1973, noone wanted them anymore and in that case it might also be cheaper to keep them standby and squeeze some more revenue out of them instead of scrapping them.



nobody has ever died from hard work, but why take the risk?
User currently offlineKC135TopBoom From United States of America, joined Jan 2005, 12061 posts, RR: 52
Reply 3, posted (3 years 2 weeks 4 days 9 hours ago) and read 8327 times:

My last flight on a TWA B-707-331 with the JT-3C TurboJet engines (J-57s) was in early 1979 (January, IIRC). It was an early morning flight from SFO to JFK, then I caught a L-1011 to BOS.

The JT-3Cs had the same amount of noise inside the airplane as the J-57s did on my KC-135A.

But that departure out of SFO was one of the few airline flights I can remember using water injection.


User currently offlineViscount724 From Switzerland, joined Oct 2006, 24080 posts, RR: 22
Reply 4, posted (3 years 2 weeks 4 days 9 hours ago) and read 8268 times:

Quoting KC135TopBoom (Reply 3):
My last flight on a TWA B-707-331 with the JT-3C TurboJet engines (J-57s)

The 707-320 (and DC-8-20/30) series used the JT4A, the commercial version of the military J-75 (used on F-105, F-106 and U-2, among others). The JT4A was quite a different (and significantly more powerful) engine than the JT3C used on the 707-120, 720 and DC-8-10.

[Edited 2011-04-02 14:51:21]

User currently onlinejetjack74 From United States of America, joined Jul 2003, 7387 posts, RR: 51
Reply 5, posted (3 years 2 weeks 4 days 8 hours ago) and read 8250 times:
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Quoting Jackbr (Thread starter):
How did they make these aircraft work for them for so long while the other main US airlines sold theirs off much sooner?

Years ago, I was flying with a 727 captain who was briefly a 707 FE at TWA in the late 70's before coming to Northwest Orient in the early 80s and we had a discussion about this very subject. According to him, he told me that while PA, AA were disposing of the JT4 powered 707's in the early 70's, TWA held on to them because they suspected that most of those aircraft would become a major source of spares(as did the early DC8's and CV880s) and that TWA could dramatically lower their mx costs by buying them up for their parts. Well, during that time, TWA was losing money with the delays and technical problems associated with the early 747 and L1011 fleet, so any money and resources they might have saved was being diverted to compensate for the growing pains of these new fleets reliability factor. So they decided to hold on to them for awhile and ride out the storm. Later on, during fuel crisis of the late 70's, they were betting that Boeing, McDonnell-Douglas and Lockheed might face a hard time in landing new aircraft orders to the point that the 707 fleet might have some trade-in value in exchange for ordering new aircraft. And they were once-again stymied that talk of pending noise-restrictions all but shredded any remaining value and all but ended that plan(United faced a similar situation with the DC8-21's that remained in their fleet in the mid to late 70s). And in the advent of deregulation and plummeting airfares/increased competition(and with the 757 on the horizon), they could no-longer justify the 707 fleet as a whole, rather then just the water-wagons. They were forced to dispose of the -331s en masse to 3rd world airlines by early 1980 as even charter airlines in the US and Europe weren't even interested let alone with any flag-carrying airlines, also with AA and PA grounding their entire 707 fleet at that time.

[Edited 2011-04-02 15:06:14]


Made from jets!
User currently onlinejetjack74 From United States of America, joined Jul 2003, 7387 posts, RR: 51
Reply 6, posted (3 years 2 weeks 4 days 8 hours ago) and read 8164 times:
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Another interesting thing, is that AAs re-engining of their -123s early on, increased the value of those aircraft to where they were more valuable than the newer -320s coming out a few years after those early -120s were built.


Made from jets!
User currently offlineABQopsHP From United States of America, joined May 2006, 848 posts, RR: 3
Reply 7, posted (3 years 2 weeks 4 days 8 hours ago) and read 8043 times:

How ironic the op asked this question. I was just thinking the same thing, over the past 3 or 4 days, never getting around to asking about it here. Thanks Jackbr.
JD CRPXE



A line is evidence that other people exist.
User currently offlineWA707atMSP From United States of America, joined Oct 2006, 2179 posts, RR: 12
Reply 8, posted (3 years 2 weeks 4 days 6 hours ago) and read 6972 times:

Quoting jetjack74 (Reply 6):
Another interesting thing, is that AAs re-engining of their -123s early on, increased the value of those aircraft to where they were more valuable than the newer -320s coming out a few years after those early -120s were built.

C. R. Smith and Bill Hogan (AA's chief financial officer) purchased their non-fan 707s, but leased the engines. A few years later, when AA wanted to re engine their non fan 707s, they were able to return the engines to the lessor. A very smart (or lucky) decision on AA's part!



Seaholm Maples are #1!
User currently onlinejetjack74 From United States of America, joined Jul 2003, 7387 posts, RR: 51
Reply 9, posted (3 years 2 weeks 4 days ago) and read 5137 times:
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Quoting WA707atMSP (Reply 8):
A very smart (or lucky) decision on AA's part!

AAlmost like the WN fuel-hedging strategy of it's day. I wonder if QANTAS did the same with the initial -138s



Made from jets!
User currently offlineJFKPurser From United States of America, joined Mar 2007, 479 posts, RR: 4
Reply 10, posted (3 years 2 weeks 4 days ago) and read 5109 times:

I'm pretty sure the JT4 was not a water-injected engine. The less powerful JT3C that powered the -131 definitely was.

User currently offlineJackbr From Australia, joined Dec 2009, 663 posts, RR: 0
Reply 11, posted (3 years 2 weeks 4 days ago) and read 5004 times:

Qantas may have done so - they were able to quickly sell of their -138Bs, many of which went to Braniff

User currently onlinejetjack74 From United States of America, joined Jul 2003, 7387 posts, RR: 51
Reply 12, posted (3 years 2 weeks 3 days 23 hours ago) and read 4758 times:
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Quoting JFKPurser (Reply 10):
I'm pretty sure the JT4 was not a water-injected engine. The less powerful JT3C that powered the -131 definitely was.

You're correct, I thought I'd read it was water-injected, but that was military variant, the J57- P-19W series



Made from jets!
User currently offlineebj1248650 From United States of America, joined Jun 2005, 1932 posts, RR: 1
Reply 13, posted (3 years 2 weeks 3 days 18 hours ago) and read 4037 times:

[quote=JFKPurser,reply=10]I'm pretty sure the JT4 was not a water-injected engine. The less powerful JT3C that powered the -131 definitely was.

The J75 engine in the F-105 Thunderchief had water injection. Whether or not the airlines that used the JT4C had provisions for water injection I can't say, but it appears it was feasible to install it.



Dare to dream; dream big!
User currently offlineJFKPurser From United States of America, joined Mar 2007, 479 posts, RR: 4
Reply 14, posted (3 years 2 weeks 3 days 15 hours ago) and read 3848 times:

The whole idea behind the -320 and -420 series was increased range and power above the-120 to achieve genuine transatlantic capability. Both planes were designed around engines which would not need water injection to achieve this - the Conway and JT4. Same went for DC8-20 and -30 -40 series. Other than the DC10-40, I'm fairly sure the 707-120 and DC8-10 were the only commercial jets to use water injection. The 720 used the JT3C but did not have water injection.

User currently offlineClassicLover From Ireland, joined Mar 2004, 4601 posts, RR: 24
Reply 15, posted (3 years 2 weeks 3 days 13 hours ago) and read 3639 times:

Quoting jetjack74 (Reply 9):
I wonder if QANTAS did the same with the initial -138s

I don't believe so, because I remember reading that the original order for 7 x 707-138 aircraft included something like 25 spare engines for the fleet. I believe the high number was based on the replacement requirements of the Constellation engines - without taking into account the reliability of the jets.

Anyway, the Qantas 138s were all converted to 138B in 1961. The aircraft were flown scheduled to SFO, then flown up to Seattle for modifications and the engines were sent to Pratt & Whitney for modification to 138B standard.

As this page - http://www.707.adastron.com/qantas/qf138-fanlist.htm says -

"The turbofan modification program entailed returning 29 of the original JT3C-6 turbojet engines to the United States where they were remanufactured as turbofan engines. These engines were progressively fifth podded back to San Francisco from where they were shipped to American Airlines in Tulsa, Oklahoma where the conversion was performed. Modified engines were then shipped to Boeing in Seattle for fitment to the aircraft. After modification to turbofan configuration, the original engines became known as JT3D-1(MC6) and the suffix "MC" was appended to its six digit serial number. A further 25 engines were modified by Qantas at Mascot. The designation MC6 applied only to engines that were converted to turbofans from JT3C-6 specifications.

In addition to the engine modifications, the 707-138B featured a number of other refinements to improve handling. All of these modifications were incorporated at the same time as the engine upgrade.


- a fin extension of 3ft 7ins (1.09m)


- a tailplane extension of 1ft 8ins (0.51m) each side


- an added ventral fin


- addition of 3 leading edge flaps on each wing


a "glove" extension to the wing leading edge between the fuselage and the inboard engine pylons"

This web site actually has a wealth of information on the Qantas 707s as well as the complete story of the restoration of VH-XBA (the former VH-EBA) -

http://www.707.adastron.com/



I do quite enjoy a spot of flying - more so when it's not in Economy!
User currently offlineViscount724 From Switzerland, joined Oct 2006, 24080 posts, RR: 22
Reply 16, posted (3 years 2 weeks 3 days 7 hours ago) and read 3390 times:

Quoting ClassicLover (Reply 15):
In addition to the engine modifications, the 707-138B featured a number of other refinements to improve handling. All of these modifications were incorporated at the same time as the engine upgrade.


- a fin extension of 3ft 7ins (1.09m)


- a tailplane extension of 1ft 8ins (0.51m) each side


- an added ventral fin


- addition of 3 leading edge flaps on each wing


a "glove" extension to the wing leading edge between the fuselage and the inboard engine pylons"

All early-production 707s went back to Boeing for the fin extension and ventral fin modifications, to overcome stability problems. Those changes resulted from the British certification authority refusing to certify BOAC's 707-436s with the original tail design.

The wing "glove" was standard on the 720 and was then extended to the -120B (and -120s/-138s converted to "B" standard).


User currently offlinetimz From United States of America, joined Sep 1999, 6708 posts, RR: 7
Reply 17, posted (3 years 2 weeks 3 days 7 hours ago) and read 3348 times:

Quoting JFKPurser (Reply 14):
Other than the DC10-40, I'm fairly sure the 707-120 and DC8-10 were the only commercial jets to use water injection.

Boeing offered the 747 with water injected engines (e.g. JT9D-7AW); did anyone choose them?


User currently offlinemilesrich From United States of America, joined Jul 2003, 1941 posts, RR: 6
Reply 18, posted (3 years 2 weeks 2 days 16 hours ago) and read 2973 times:

Quoting KC135TopBoom (Reply 3):
My last flight on a TWA B-707-331 with the JT-3C TurboJet engines (J-57s) was in early 1979 (January, IIRC). It was an early morning flight from SFO to JFK, then I caught a L-1011 to BOS.

The only JT-3C powered Boeing airlinerss were the -100 707's and the 720's. The only 707 customers for these aircraft were PA -121's, AA -123's, CO -124's, TW -131's, QF -138's, and Cubana -139's, and their aircraft were never delivered but later leased by Western. All of the -121's, 123's, 138's, and 139's that were not w/o were converted to B models with JT-3D low bypass fans. As far as the 720's, only AA converted their -023's to the B model. UA, EA, BN, EI, EA and PN did not. All other 720 customers purchased their aircraft with JT-3D's. Only AA, TW and QF purchased 707-100B's from Boeing. 720's did not have water injection.


The JT-3Cs had the same amount of noise inside the airplane as the J-57s did on my KC-135A.

But that departure out of SFO was one of the few airline flights I can remember using water injection.
Quoting jetjack74 (Reply 5):
According to him, he told me that while PA, AA were disposing of the JT4 powered 707's in the early 70's, TWA held on to them because they suspected that most of those aircraft would become a major source of spares(as did the early DC8's and CV880s) and that TWA could dramatically lower their mx costs by buying them up for their parts. Well, during that time,

AA never operated JT-4 equipped aircraft. BN was the only factory customer for the domestic range JT-4 powered -200.

CO sold their -124's for two reasons, they were a small subset of aircraft. The took delivery of five airframes but two were written off, and they had no need with their route structure for the aircraft. The 720B had more range, and was cheaper to operate. The airline took delivery of some 707-324C's but these were used on MATS charter flights during the Vietnam war, but with the sale of the 707-124's to TWA, their fleet was standardized with three types, 720-024B's, 727-224's and DC-9-14/15's.

TWA to my knowledge did not purchase any other carriers JT-4 powered 707-300's. And 880's never had any substantial value for parts. Of the 65 880's built, TWA and DL had 44 or 45 of them. Delta had 17 on which one was destroyed in a training accident, and TWA I believe ended up with 30 although I would have to go back and check if they operated all the Toolco owned aircraft that were originally used by Northeast. The only other carrier that operated more than a couple aircraft was Cathay Pacific TWA and Delta retired their fleets last in late 1973 early 1974. TWA's aircraft sat at MCI for a while and then were ferried to Mohave where they were bought by American Jet Industries who planned to convert the to Cargo aircraft. One or two were converted, the rest were not, and just sat there for years. Delta had a w/o at ORD in December 1972, and the remaining 15 aircraft were sold, but there was demand for parts because once Delta and TWA grounded their fleets, there were no operators using the aircraft on a regular basis, unless you count Elvis Presley or a few travel clubs.



Quoting jetjack74 (Reply 5):
McDonnell-Douglas and Lockheed might face a hard time in landing new aircraft orders to the point that the 707 fleet might have some trade-in value in exchange for ordering new aircraft. And they were once-again stymied that talk of pending noise-restrictions all but shredded any remaining value and all but ended that plan(United faced a similar situation with the DC8-21's that remained in their fleet in the mid to late 70s). And in the advent of deregulation and plummeting airfares/increased competition(and with the 757 on the horizon), they could no-longer justify the 707 fleet as a whole, rather then just the water-wagons. They were forced to dispose of the -331s en masse to 3rd world airlines by early 1980 as even charter airlines in the US and Europe weren't even interested let alone with any flag-carrying airlines, also with AA and PA grounding their entire 707 fleet at that time.

United's DC-8-21's were retired at the beginning of 1978 and were traded into Boeing on 727-222 Advanced aircraft. Boeing flew them to Kingman, AZ were most of them were scrapped.

These aircaft, along with JT-4 powered 707's couldn't turn a profit with 100% load factor after the 2nd oil price shock that was brought on with the fall of the Shah of Iran.

And this same price shock caused the carriers operating JT-3D powered 707's and DC-8's to ground those in short order too. United and Delta, the last two airlines to fly substantial numbers of DC-8-50's grounded theirs in 1980-81. In early 1981, American announced it would ground all of its 707-123B's, 707-323B's and 707-323C's and by September, they were gone. This caused AA to have to reduce service, but their purchase of a number of BN's 727-227B's allowed them to make the adjustment without severely curtailing service, as they were operating close to 100 707's when the announcement was made.

Most JT-3D powered 707's were eventually purchased by the USAF and used in the KC-135E program, where the tail planes, engines and other parts were used to upgrade the KC-135A's.

Quoting jetjack74 (Reply 6):
Another interesting thing, is that AAs re-engining of their -123s early on, increased the value of those aircraft to where they were more valuable than the newer -320s coming out a few years after those early -120s were built.
Quoting ebj1248650 (Reply 13):
The J75 engine in the F-105 Thunderchief had water injection. Whether or not the airlines that used the JT4C had provisions for water injection I can't say, but it appears it was feasible to install it.
Quoting JFKPurser (Reply 14):
The whole idea behind the -320 and -420 series was increased range and power above the-120 to achieve genuine transatlantic capability. Both planes were designed around engines which would not need water injection to achieve this - the Conway and JT4. Same went for DC8-20 and -30 -40 series. Other than the DC10-40, I'm fairly sure the 707-120 and DC8-10 were the only commercial jets to use water injection. The 720 used the JT3C but did not have water injection.

TWA got stuck with their fleet because, as has been pointed out, they were weak financially, and kept their JT-4 powered aircraft too long to the point where there was no market for them. TWA was also the last major operator of the 707. As far as Pan Am, they had the same financial problems as TWA, and one of the problems was their fleet. Too much dependence on, and/or too many 747-100's, too many 707's even though as was pointed out, they dumped their JT-4 powered aircraft in the early 707's and then the failure or inability to order replacement aircraft. They purchased L-1011-500's but only 12 of them, and I am not "going there" in this post, and then bought A-310's but it was too little too late. They probably would have been better off to keep NA's DC-10 fleet and have added to it, rather than trading it to AA for more 747's.


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