J40, J46, J65 and J67 - Why did they fail?

gral_rj

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If I'm posting this in the wrong board, please tell me, I'll repost the question in the right place.

A question that comes and goes to my mind is why those engines failed, dooming or almost dooming many projects with them. The J40 and J46 failures took Westinghouse out of the jet engine business, forcing some aircraft either to take engines not suited to them(F3H Demon and the J71), or languish with underpowered engines(F7U Cutlass and the J34). What I've found about the J40 seems to imply the afterburner was the problem; the engine without it passed its tests(not without trouble), but the J40-WE-8, that had the afterburner to meet its high performance goals was a miserable failure. The J46 is mentioned only in passing together with the J40 failure, with no clue on what went wrong.

The J65's problem definitely was the afterburner; the un-reheated engine seems to have done OK on the B-57, A-4, F-84F, FJ-4 and other aircraft I doubtlessly I'm forgetting to mention, but the afterburner on the F11F engine simply didn't give the needed thrust, making the Tiger barely supersonic. The J67, also a British engine(Olympus) built under license by Wright, was considered for many projects, but eventually none used it, those that went forward turning to P&W and the J75 for their needs.

So, what exactly went wrong to each of these engines?
 
This thread covers a pretty wide range of engines, so there may not be a common thread, However in the case of the Wright corporation engines, the major problem could possibly have been in the management and operation of the company. The Curtiss-Wright corporation was perhaps one of the first USA corporations to suffer the malais of management that neither really understood how to make money or to deal with a high level technology based product line, which seems to have reached an epidemic level in the last decade.

Best regards,

Artie Bob
 
Westinghouse may have become overconfident following its success with the J30 and then in successfully doubling its thrust with the J34. Doubling the thrust yet again with the J40 proved to be more difficult than expected and qualification of the basic engine fell behind schedule. (My impression is that the J46 was a scaled-down version of the flawed J40 design.) Westinghouse probably failed to devote enough engineering resources to solve the problems initially, although there is some question whether a more aggressive response would have been enough to keep the engine from being a failure. While Westinghouse was trying to solve the J40's problems, Pratt & Whitney and General Electric were developing innovative, high pressure ratio compressor designs for the J57 and J79 respectively that avoided the design shortcomings that the J40 suffered from.

The basic J65 was a license-built British design, the Sapphire, so the basic engine was not the problem. The afterburner, as far as I know, was added by Wright. The afterburner development fell behind schedule and it never met the original specification in thrust. However, even if it had, it again was up against the J57 and then the J79, both of which had more thrust and better thrust to weight performance.
 
J65 was a full two years late to production, by which time it was about 10 years old in basic conception and was soon superceded by later designs. The J67 based around the Olympus was a newer conception engine in 1950 when the agreements were signed, but the productionisation of the J65 was Curtiss's first priority and so the J67 was equally late in arriving, and as Tommy said there were better engines around by then. If they'd stuck to building the J65 as a direct Olympus copy and *then* started redesigning it, perhaps things might have been different.
 
Out of curiousity...

Did the J-65 / Armstrong Siddely Sapphire have a rather slow spool-up rate? I've never been able to find such data
 
I'm trying to figure out why the Navy was so enthusiastic about the J40 when engines like the J57 were being developed around the same time to higher performance specs. I suppose that J40's smaller diameter was part of the attraction to the infamous Westinghouse engine. Fortunately Ed Heinemann & co had the foresight to consider the J57 when designing the Skyray & Skywarrior, although the F3H would not be so lucky.
 
Your timings are off, thats why it doesn't make sense. J57 was a full generation later in conception than J40.

P&W offered the JT3-6 (single spool, 6:1 compression ratio) against the J40 for the Navy, and lost. They went back to the drawing board and came up with the JT3-8, which used dual spools and 8:1 compression and was aimed specifically at the Air Force B-52 role. This meant fuel consumption was absolutely critical and they pushed compression ratio to 10:1 with the JT3-10, at a time when other US engine makers thought 6:1 was the maximum useful compression ratio possible. Then, they did a complete redesign because JT3-10 was overweight, saving about 500 lbs and producing the JT3A (J57) with 12:1 compression ratio and unparalleled specific fuel consumption for its day.

The problems Westinghouse experienced with J40 delayed it to the point that the later technology J57 was already looking viable, so it was a no-brainer to go with the newer engine.
 
Someone please show us the picture of J40. It's front shape was very unique.
I really hope engine section of this forum.
 
A couple of years ago I was sent a paper on the Westinghouse jet engine debacle that went into a broader look at why they failed. Part of it revolved around the lack of real understanding of the nuances of jet engines vs. Westinghouse's previous (and at that time, ongoing) experience in the steam turbine business. Much of their business model, covering R&D, manufacturing, etc. relied heavily on their steam turbine experience and was one of the primary reasons for their eventual failure in the jet engine business.

I'll dig that up - it's a fairly large file so will need to be hosted elsewhere.

There is an excellent series of articles in the American Aviation Historical Society Journal around the mid to late '70s that covers the rise and fall of Curtiss-Wright as a whole and in covering that, notes their jet engine portion of the business. To put it simply, the leadership of Curtiss-Wright in the war years was from the banking industry and handled the business in much the same manner - return on investment style management. This was pretty easy to do with the sheer volume of business coming in (P-40s, radial engines and propellers) but post-war, the leadership chose to continue bring in the money near term and not concern themselves with the long term picture and continued production of R-3350 radial engines and propellers propped up the bottom line with no real need for substantial outlays for R&D. Instead of developing their own line of jet engines (and the resulting outlay for R&D, etc.), they went with license agreements and with engines that by the time they acquired the license, were at least a half generation behind what others were doing. As I recall, J-65 failures were primarily bearing related (was that also an issue with the Sapphire back home in Great Britain?) and the J-67 was never developed to its full potential because the leadership was not willing to put in the $$$ for the R&D to do so. I have those AAHS Journals reasonably handy - I'll dig them up and pull out some of the highlights and post them.

Enjoy the Day! Mark
 
blackkite said:
Thanks. It had very interesting intake shape.

It was a bifurcated intake in expectation that in most cases the airframer would provide air from two ducts, either from two side-mounted intakes or as a result of splitting the airflow from a single nose-mounted intake around the cockpit. The accessory section (starter, hydraulic pump and electric generator drives) was mounted between the two inlets and driven by the shaft that linked the compressor to the turbine.
 
Not only CW. “Licence” surpasses “copy”: UK redraws to fabricate to BS, not US MilSpecs, and is addicted to “improvement”: “A quirk of (WS.55 Whirlwind’s UK-)self-sealing fuel tanks rendered the last 40 gallons unuseable (but that was its total) typical fuel load” R.G Bedford, RAF Rotors, SFB,1996, P57. At the level of Unit engineers' consumable materials - nuts and bolts - it's hard to stock MilSpec AN/MS bits for most kit, BritStandard for some. So, while we're redrawing for that purpose, let's just "improve" here...and here...and here.

I don't take as the simple A (to cause of such "failures" as Westinghouse, CW) that bean-counters ruled, (not)-OK. Neither CW, nor GE, nor RR, nor anyone (after Power Jets, pre-War) in at the creation of reaction thrust was expected to invest dime one, in fabrication or in R&D. WW2, then Berlin Blockade, then the Korean War paid for it all; Basic Research was disseminated free, from NACA and NGTE. Creating a nice gap between expense and income was/is as central a Task on designers as is perfection of product. Barnes Wallis, for example, was simply wrong in this position on Wellington: ‘“the practical shop element of personnel (was) bitterly opposed to (my) geodetics”.(He) was persuaded to accept design changes in the interests of cheapening manufacture’ S.Ritchie, Industry and Air Power,Cass, 1997,P83. A cause of failure at market of many UK engineering products (I offer BEAGLE smallcraft) was unfriendly, impractical build/operation...of doubtless couth engineering solutions.

US took Whittle data/specimens in 1940/41 and assigned them to non-Aero teams that understood spinning metal - Allis Chalmers, GE, Westinghouse. The two-fold logic was: that reciprocating-Aero-engine folk were a bit busy; and that power turbines/superchargers seemed to be a sensible entry point (UK tried AEI, BTH, Metro-Vick, Rover and Vauxhall in similar vein). Pistoneer CW failed at turbine market: in UK, so did Napier. RR, after odd Avon hiccups, crossed-over; so did Pratt. That's why MoS and DoD tried to fund 2 designs for risky Tasks, as "insurance". I suggest the more pertinent Q is not why some early turbine designs failed (too many As), but what was in the Corporate genes that caused GE to come from dull industry, to their present Aero strength, civil and military; or RR to surmount the humiliation of bankruptcy, to near-match GE? I submit that a couple of man-managers, inspirational team leaders, might have been central.
 
Greetings All -

As a follow up to my earlier comments, the Westinghouse study can be downloaded at:


And the overview of the rise and fall of Curtiss Wright was in the American Aviation Historical Society Journal, Winter 1994, Vol. 39 No. 4.

HTH! Mark
 
See my books: Westinghouse J40 Development History and Technical Profiles, (out on Amazon.com and Barnes & Noble) and my soon to be published Westinghouse J46 Development History and Technical Profiles, same locations.

The J40 failed because the higher power versions continued to fail on the test bed. The original contract engines passed their 150 hour tests but development had shifted to the high power versions and the many early bugs of the lower power versions never got the attention needed. Meantime, Douglas had moved the F4D-1 to the J57 and McDonnell reconfigured their F3H-1N to be a lot heaver as an all weather missile armed version that had to have the higher power engines that never emerged. The Air Force moved to an A/B equipped J71 but it was two years late due to development issues of its own and BuAer elected to fly one squadron of early F3H-1N's using the poorly developed lower power engines and had so much trouble they grounded the airframes and used most of them for mechanic's training school. The A3D-1 moved to J57's as well due to early J40-WE-6 unreliability (not thrust issues) and discovered the airframe now had much greater range and the heavier engines solved a flutter problem on that long aspect ratio wing.

The J46 should have been an easy development due to years of expensive experiments paid for by the Navy, but matching an A/B to the engine turned out to be far harder than anyone anticipated. And, as usual, Westinghouse had bid very low weight (at BuAer's request mind you) and the struggle to keep weight down while solving reliability problems drove it up made the engines very late. In fact, the J40 ate up the resources at Westinghouse and the J46 languished. In the end, it was not far off its design thrusts but had low TBO's below 150 hours due to turbine issues and the F7U-3 Cutlass had grown significantly in weight and needed more thrust than the J46 could be developed to give. Everyone seemed to forget that the J46 WAS the stretch version of the J34 and was designed to give the limit of the size of the engine. There was no growth potential in the design for later development. The F7U's had their own issues and were withdrawn early due to a high crash rate, for which the engines bore only a small proportion of the blame.

Both books use the original primary sources left in the archives to trace the development.

Al Casby, at Mid-Century Aviation in Phoenix, AZ is rebuilting an F7U-3 to airworthy status and now has purchased all known available J46 engines for parts that are not in museums. His "Project Cutlass" is a long held dream and I wish him well! If anyone hears of an available J46 regardless of its condition, reply to this or send me a note at: pj.chris@verizon.net

Paul Christiansen
 
Curtiss-Wright really were idiots. Not only did they had the rights for Sapphire (J65) and Olympus (J67).
In 1957 they also bought the rights for Orenda PS-13 Iroquois... and they did nothing of it (well maybe because of Black Friday and the Canadian government erasing the engine from the face of Earth).
 
The Navy went with Westinghouse for jet engines during the war simply because they weren't already 'taken' by the USAAF as a vendor. That meant the Navy got priority for Westinghouse engines rather than having to get in line to get ones from GE, or Allis Chalmers, Allison, etc. That was simply a bureaucratic inter-service thing.

Westinghouse was a fail mostly because the company's management wouldn't go all in on jet engines. They saw them as nothing more than a new part of their existing steam turbine division. The company's engineers also stuck with conservative designs that meant that their engines under-performed compared to those from GE and others.

As for Curtiss and Curtiss-Wright, that corporation was already on the ropes in 1945. The few jet aircraft designs they did turned out rather pathetic and post WW 2 the company was on a steep decline. By late 1948 Curtiss-Wright was bought out by North American Aviation becoming another division of that company. In engine manufacturing the company really displayed a lack of enthusiasm for moving to jet engines. So while they were able to gain some sales of licensed British engines, these were really uncompetitive with US home grown ones due to the licensing fees and restrictions.

It's the same reason that Packard stopped making the RR Merlin as soon as the war ended. RR wanted too much cash per engine in license fees to make it profitable for Packard to continue production.
 
Well, not exactly, at least in one respect. After wartime orders were cancelled by the government in late 1945, Curtiss-Wright (along with all the major aircraft manufacturers) retrenched, closing many facilities. The Columbus, Ohio facility was later purchased by North American Aviation during the Korean War initially to serve as a second source production center for F-86Hs and F-100s. Many C-W workers went back to work for NAA.

(The C-W facility at St. Louis was later occupied by McDonnell aircraft where all Banshees, Demons, Voodoos and many Phantoms and Eagles were built. Boeing later moved out of the facility and it stands derelict today.)

Curtiss-Wright still exists today as a diversified tier-3/4 components company (about 50% defense) with sales of almost $2.5 billion last year.

There is a strong narrative that C-W's marginalization in the post-war market was at least partially due to the banking interests' pressure on management to retain wartime profits and to not risk adverse exposure.
 
Speaking of failed Curtiss-Wright engines, what on Earth became of the J59 and the J61? It's almost impossible to find any information about them other than that they apparently never made it off the drawing board.
 
There is a little bit on the Curtiss-Wright XJ61 in Anthony Chong's Flying Wings & Radical Things ... although he's actually talking about the TJ-15 turbojet proposed for the Northrop N-65. On pp 73-74, Chong speculates that since the XJ61-W-1 had the "in-house designation TJ-6, the TJ-15 was probably a proposed XJ61-W-3". Ratings for the TJ-6 mentioned were 10,000 lbf dry, 11,000 in reheat. Chong further speculates the the TJ-15 might have been rated at 12,000 lbf.

The only mentions of the J59 are Curtiss-Wright internal designations: TJ-7 for the XJ59-W-1 and TJ-14 for the XJ59-W-3.
 
Yeah, but between that and mention one of them (referred to as the TJ-6 or TJ-7) was considered for Curtiss's entry for a naval attack aircraft which lost out to the Douglas Skywarrior in Zichek's book there's nothing else in print anywhere.

It's as if both projects just disappeared from the face of the Earth.
 
The J46 should have been an easy development due to years of expensive experiments paid for by the Navy, but matching an A/B to the engine turned out to be far harder than anyone anticipated. And, as usual, Westinghouse had bid very low weight (at BuAer's request mind you) and the struggle to keep weight down while solving reliability problems drove it up made the engines very late. In fact, the J40 ate up the resources at Westinghouse and the J46 languished. In the end, it was not far off its design thrusts but had low TBO's below 150 hours due to turbine issues and the F7U-3 Cutlass had grown significantly in weight and needed more thrust than the J46 could be developed to give. Everyone seemed to forget that the J46 WAS the stretch version of the J34 and was designed to give the limit of the size of the engine. There was no growth potential in the design for later development. The F7U's had their own issues and were withdrawn early due to a high crash rate, for which the engines bore only a small proportion of the blame.
Some time back (but within the last 4 years and probably within the last 2), I bumped into a gent on FB who said he had a flying F7U. According to him, the problem was in how the engine was controlled for thrust. Apparently, the engine stayed at about 100% rpm and the nozzle varied in shape to control thrust. (first I have ever heard of such a control arrangement, BTW). Open the nozzle too fast and the engine blows the flames out.
 
"...and the engine blows the flames out."

Is this akin to the infamous SR-71 'Un-Starts' ??
 
Apparently, the engine stayed at about 100% rpm and the nozzle varied in shape to control thrust. (first I have ever heard of such a control arrangement, BTW). Open the nozzle too fast and the engine blows the flames out.
That's a relatively normal control mode for carrier approach because you can vary thrust much quicker than changing engine rpm. I imagine you normally just varied rpm in other flight modes.
 
"...and the engine blows the flames out."

Is this akin to the infamous SR-71 'Un-Starts' ??
No, an unstart is when the shockwaves get out of position at supersonic speeds. The inlet stops flowing air, kinda like putting your hand over the extension nozzle of a vacuum cleaner. Engine keeps turning, just with a lot less air than it needs so you loose basically all your thrust on one side. Plane yaws so fast that the side of the cockpit that still has power smacks the crew upside the head. But the inlets can restart in a second or two and were modified to restart automatically any time the inlet pressure between the two engines differed by much. And you're at 85,000ft so it's not a major emergency.

With the J46, open the nozzle too quick and the engine goes out. Now you need to do an emergency in-flight engine restart while in a landing approach. Hopefully the core is still spinning fast enough to relight just by turning the ignitors on.
 
That's a relatively normal control mode for carrier approach because you can vary thrust much quicker than changing engine rpm. I imagine you normally just varied rpm in other flight modes.
Okay, that does make sense. It just sounded really really weird. Normally the fuel controller adds more fuel to increase TIT and energy going into the turbines to add rpm and add thrust for a basic jet.

I had thought that the J46 had a slow spooling problem, so adding power was very slow.
 
A couple of years ago I was sent a paper on the Westinghouse jet engine debacle that went into a broader look at why they failed. Part of it revolved around the lack of real understanding of the nuances of jet engines vs. Westinghouse's previous (and at that time, ongoing) experience in the steam turbine business. Much of their business model, covering R&D, manufacturing, etc. relied heavily on their steam turbine experience and was one of the primary reasons for their eventual failure in the jet engine business.

I'll dig that up - it's a fairly large file so will need to be hosted elsewhere.

There is an excellent series of articles in the American Aviation Historical Society Journal around the mid to late '70s that covers the rise and fall of Curtiss-Wright as a whole and in covering that, notes their jet engine portion of the business. To put it simply, the leadership of Curtiss-Wright in the war years was from the banking industry and handled the business in much the same manner - return on investment style management. This was pretty easy to do with the sheer volume of business coming in (P-40s, radial engines and propellers) but post-war, the leadership chose to continue bring in the money near term and not concern themselves with the long term picture and continued production of R-3350 radial engines and propellers propped up the bottom line with no real need for substantial outlays for R&D. Instead of developing their own line of jet engines (and the resulting outlay for R&D, etc.), they went with license agreements and with engines that by the time they acquired the license, were at least a half generation behind what others were doing. As I recall, J-65 failures were primarily bearing related (was that also an issue with the Sapphire back home in Great Britain?) and the J-67 was never developed to its full potential because the leadership was not willing to put in the $$$ for the R&D to do so. I have those AAHS Journals reasonably handy - I'll dig them up and pull out some of the highlights and post them.

Enjoy the Day! Mark
I don't know if this is what you were thinking of, but this was interesting:
https://www.enginehistory.org/GasTurbines/EarlyGT/Westinghouse/WestinghouseAGT.pdf
 
There is an excellent series of articles in the American Aviation Historical Society Journal around the mid to late '70s that covers the rise and fall of Curtiss-Wright as a whole and in covering that, notes their jet engine portion of the business.
.....
Instead of developing their own line of jet engines (and the resulting outlay for R&D, etc.), they went with license agreements and with engines that by the time they acquired the license, were at least a half generation behind what others were doing. As I recall, J-65 failures were primarily bearing related (was that also an issue with the Sapphire back home in Great Britain?) and the J-67 was never developed to its full potential because the leadership was not willing to put in the $$$ for the R&D to do so. I have those AAHS Journals reasonably handy - I'll dig them up and pull out some of the highlights and post them.

Enjoy the Day! Mark
The Sapphire was a hand tooled production of the British firm Armstrong Siddeley for which the Curtiss-Wright Aeronautical Division at Wood Ridge NJ, had acquired a manufacturing license. However, the J65, as the Air Force version of the Sapphire was designated, was proved initially difficult to adapt to American specifications and manufacturing. Curtiss-Wright spent a lot of resources - and lost a lot of time - in redesigning and americanizing them before starting manufacture. They were more than 2,000 changes between the corresponding Sapphire and J65, some of them very substantial, both in specifications but also in materials and manufacturing methods (substantial parts, dimensionally similar, were completely redesigned by CW in order to use different alloys and different processes). An example is substituting the Sapphire's machined mid-section solid forged diffuser frame with a fabricated one of welded nodular iron.

The J65 steel-bladed engine had experienced a number of first-stage compressor-blade failures in service by 1955. The failures are the result of the blade vibrations and consistently occur in the second serration of the blade root. Stress analysis of the fir-tree-type roots of the first three stages of the compressor (the most critical stages from the vibration aspect) was undertaken to determine if it was possible to eliminate failures by redesigning the roots. However, Armstrong Siddeley had already found this issue, and developed a "fix" - but Wright just had to make their own study and "fix", as they had made so many changes in the engine.

Due to the urgent need for improved fighter bombers since the outbreak of the Korean War, the Air Force in December 1950 selected the Buick Division of the General Motors Corporation as the second source for the Sapphire engine. In June 1952, when the Air Force finally accepted the first 2 YJ65-W-1 engines, neither had yet completed the required 150 hour qualification test.

In service, the J65 had a reputation for oil issues. However, the issue turned out to be primarily with the Buick-built J65-BW-1/-5 engines, which tended to burn oil and fill up the cockpit with smoke on B-57s (the problem first appeared in 1954), and was fixed by first replacing the compressor sections, then finally by ending Buick production - Wright-built engines did not have those problems. With the FJ-3 Fury (the first use of the J65 in a catapulted aircraft) the J65-W-4 tended to "dump" oil during catapult shots, resulting in the engine seizing shortly thereafter - this was first experienced in 1955 after several squadrons were in service. This was eventually fixed, and the J65 turned into a fairly reliable carrier engine for the FJ-4 (J65-W-16), F11F-1 (J65-W-18), and A4D-1/2/2N (J65-W-4B/-16/-20).


While C-W had obtained a similar production license for the Olympus engine as the J67, they were unable to interest the USAF or USN in choosing the J67 for projects instead of the J75 (the Olympus Mk.201 had a similar thrust), mainly due to an expectation by the USAF and USN of similar issues being repeated with this engine.
 
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The Sapphire was a hand tooled production of the British firm Armstrong Siddeley for which the Curtiss-Wright Aeronautical Division at Wood Ridge NJ, had acquired a manufacturing license. However, the J65, as the Air Force version of the Sapphire was designated, was proved initially difficult to adapt to American specifications and manufacturing. Curtiss-Wright spent a lot of resources - and lost a lot of time - in redesigning and americanizing them before starting manufacture. They were more than 2,000 changes between the corresponding Sapphire and J65, some of them very substantial, both in specifications but also in materials and manufacturing methods (substantial parts, dimensionally similar, were completely redesigned by CW in order to use different alloys and different processes). An example is substituting the Sapphire's machined mid-section solid forged diffuser frame with a fabricated one of welded nodular iron.
Makes sense.

Have you seen how many changes there were on the Bofors 40mm design/blueprints, or even on the Packard Merlins?
 
but post-war, the leadership chose to continue bring in the money near term and not concern themselves with the long term picture

So Curtiss-Wright in a sense was a precursor of today ramping business model plague: short term money, screw long term viability.
 
Greetings All -

Came across a book "Whatever Happened to Curtiss-Wright?" by Robert W. Fausel in a local antique shop. The book is based on personal recollections by C-W employees of the waning days of C-W as it existed at the end of WWII and the termination of the aircraft portion of the business. Will starting reading it this evening - a friend read it some time back and thought it was an excellent read.

Enjoy the Day! Mark
 
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