Western engine reliability

Discussion in 'Aviation' started by Tante Ju, Jan 15, 2013.

  1. Tante Ju

    Tante Ju Banned

    Joined:
    Jan 24, 2011
    Messages:
    664
    Likes Received:
    3
    Trophy Points:
    0
    Question arose in different thread. Supposedly Western engines had more lifespan than Soviet, German or Japanese engines. I open this thread to find out truth of these engines. What was TBO, how long they lasted in frontline conditions (not training flights or manufacturer sell brochure)

    Source. Spitfires over the Kuban
     
  2. Tante Ju

    Tante Ju Banned

    Joined:
    Jan 24, 2011
    Messages:
    664
    Likes Received:
    3
    Trophy Points:
    0
    #2 Tante Ju, Jan 15, 2013
    Last edited: Jan 15, 2013
    Allison engine (in P-39)

    Part 3

    Allison engine in P-40

    http://lend-lease.airforce.ru/english/articles/golodnikov/part4.htm
     
  3. Tante Ju

    Tante Ju Banned

    Joined:
    Jan 24, 2011
    Messages:
    664
    Likes Received:
    3
    Trophy Points:
    0
    Griffon engine


    Spitfire trials from 1946. First engine develops rough running after 41 hours. Second engine fails 61 hours.

    griffonenginetbo.png

    Trials at boosted setting during war. Engine fails on first flight made.

    RAE 1501

     
  4. Tante Ju

    Tante Ju Banned

    Joined:
    Jan 24, 2011
    Messages:
    664
    Likes Received:
    3
    Trophy Points:
    0
    Sabre engine... :D

    RAE 1501


    Curiously - it was famous pilot Eric Brown flying one of Tempest. He recalls (also where funny story when he landed).

    The Hawker Tempest Page
     
  5. parsifal

    parsifal Well-Known Member

    Joined:
    Apr 6, 2008
    Messages:
    10,678
    Likes Received:
    676
    Trophy Points:
    113
    Occupation:
    Urban Design/Strategic Studies Tutor
    Location:
    Orange NSW
    Cant help much Im afraid. i do have a secondary source that says the average life expectancy of allied fighters in 1944 was 8 months.
     
  6. Jack_Hill

    Jack_Hill Member

    Joined:
    Mar 18, 2010
    Messages:
    192
    Likes Received:
    1
    Trophy Points:
    16
    Location:
    France
    #6 Jack_Hill, Jan 15, 2013
    Last edited: Jan 15, 2013
    Hi.
    Intricated thread indeed.

    Bit lost with such an amount of interesting questions, so i stopped reading after third post, but i'll read farther later.
    Seems that the two first post concerns Russian testing : Merlins and Allisons.
    So, whe may ask a question maybe.
    Did testings occured in Russia, Ukrainia, Siberia or anywhere else in Ussr ?
    wich season ?
    Wich fuel ?
    Wich lubricants ?
    Did tests occured within usual low alt Russian aerial warfare or else ?
    To me, any well designed, high performance engine breaking at 60 hours (of course considering the conditions of use) simply means an overhaul revision at 40 hours of run.
    And engeneering hard work to solve that lack of reliability and/or quick availabilty for new engines replacement.
    But i may be simplist.
     
  7. Juha

    Juha Well-Known Member

    Joined:
    Jan 8, 2007
    Messages:
    3,734
    Likes Received:
    65
    Trophy Points:
    48
    Location:
    Helsinki
    Hello Tante Ju
    did you miss the last chapter of Zlobin's article

    "It is worth noting that the mastery by the flight crews and technical personnel of the exploitation of the Spitfire and Merlin 45 and 46 engines was accomplished directly in the regiment. The senior squadron technicians and regiment engineers by specialty were the basic supervisors in technical training, despite a lack of special literature on the equipment. A review of mistakes in use of the equipment was conducted regularly with both the flight crews and mechanics of the regiment. These reviews were important, because no one in the division or the regiment had any experience in the repair and use of the aircraft and engine. Thus, every new revelation, after careful discussion and consultation, was quickly implemented on the equipment. In any event, the following conclusion was reached concerning these monthly reviews of the use of the Spitfire: “The regiment’s technical personnel coped well with both exploitation and repair, and in the future, if they had had occasion to service this same type of aircraft, could have completely fulfilled their obligations.”
     
  8. Shortround6

    Shortround6 Well-Known Member

    Joined:
    Jun 29, 2009
    Messages:
    9,773
    Likes Received:
    802
    Trophy Points:
    113
    Occupation:
    retired Firefighter
    Location:
    Central Florida Highlands
    #8 Shortround6, Jan 15, 2013
    Last edited: Jan 15, 2013
    The Russian pilot being quoted fully admits the Merlin and Allison engines were NOT being run according to manufactures recommendations, which rather affects the expected life of the engine.

    Tomahawks used the early "C" series engines which had a number of problems, The Kittyhawk started with the -39 engine which was an "F" with a number of improvements. Later Kittyhawk's used several newer versions of the Allison P-40Ks used an F4 instead of the F3 and the M/Ns used F20s, F26 and F31 engines.

    "Vees for Victory" claims that F26 was rated at 750 hours between overhauls by the end of the war.
     
  9. davparlr

    davparlr Well-Known Member

    Joined:
    Mar 23, 2006
    Messages:
    2,934
    Likes Received:
    105
    Trophy Points:
    63
    Occupation:
    retired avionics engineer
    Location:
    Southern California
    If I remember correctly, Bud Anderson stated he never aborted a mission due to aircraft problems. He flew the P-51 "Old Crow".
     
  10. DerAdlerIstGelandet

    DerAdlerIstGelandet Der Crew Chief
    Staff Member Moderator

    Joined:
    Nov 8, 2004
    Messages:
    41,768
    Likes Received:
    684
    Trophy Points:
    113
    Occupation:
    A&P - Aircraft Technician
    Location:
    USA/Germany
    #10 DerAdlerIstGelandet, Jan 15, 2013
    Last edited: Jan 15, 2013
    Yes but was the engine or the airframe?

    I do however find it hard to believe that any of the major engines from the major nations (USA, England, Germany, Japan for example, but not to name them all), would last such a short lifetime. Don't take me wrong, I am sure that routine maintenance was required on all of them on periodic limits, but I am sure they could all be measured in hundreds of hours for total lifetime during the war.

    Whether the airframe survived the war for a very long time is a whole other problem though.
     
  11. bobbysocks

    bobbysocks Well-Known Member

    Joined:
    Feb 28, 2010
    Messages:
    3,811
    Likes Received:
    181
    Trophy Points:
    63
    Location:
    Pennsylvania
    the first time the air force personnel witnessed a VVS scramble ( in poltava iirc) they didnt have too many good things to say about their practices. pilots got into planes, as soon as the engines were started they were immediately pushed to full throttle and the plane airborne. neither the pilots or ground crews did any pre-flight checks or engine warm up. the pilots took off in the direction the plane was facing at the time regradless of the wind direction ( cross wind, down wind..didnt matter) or placment of other ac. there was no co-ordination from a tower...ac would often criss cross each other taking off. whether this was a show for the yanks or standard practice...??? but if it was a sample of how vvs treatment of machinery then its no doubt they had a higher attrition rate for ac engines. in contrast to comments i have heard and read about us fighter groups...the planes looked weathered and well used but mechanically they were as goodor better than when they rolled off of the assembly line. a funny story about a vvs pilot...

    The Russian Pilot
     
  12. parsifal

    parsifal Well-Known Member

    Joined:
    Apr 6, 2008
    Messages:
    10,678
    Likes Received:
    676
    Trophy Points:
    113
    Occupation:
    Urban Design/Strategic Studies Tutor
    Location:
    Orange NSW
    Im not sure, but would assume its the airframe. I also would find it hard to believe that a complete engine overhaul would be needed after 50-60 hours. I dont have any experience with aero engines, of any kind, but I do have some experience with auto engines, including supercharged and turbocharged engines. Just enough to get myself into trouble......

    Its a more believable propoosition that fuel quality issues and overtaxing of the boost, or the use of water methanol or other fuel enhancements might very well burn too hot, or fast, or not fast enough. Its a somewhat different matter with supercharged or turbocharged engines. these systems are basically force feeding the fuel air mixture into the cylinder. If the cylinder is not designed or strengthened to take the additional fuel and air being forced into the pot, there is a real risk of blowing the cylinder heads off the engine. Thats why most turbos have to run on a fairly restrained overboost. In automotive racing it also usually means you have to derate the engine.....reduce the compression ratio and/or the boost rating of the engine. I would expect that an engine being run above its boost levels on a sustained basis, or running a turbo using higher octane rated fuel on a sustained basis is bound to have reliability problems. You can partially offset that risk by using higher standards of construction in the engine build....so called blue printing of the engine. Better stronger components does help if you absolutely need to run the thing over its design specs.

    Poor componentry, overtaxing of the engine, overrated fuel, poor quality fuels are all going to put the engine life at risk. I would expect that this basic understanding would easily apply to aero engines in the same way as they do to high performance auto engines. Fuels usually lead to early burn out of the upper parts of the engine.....particulalry injectors, valves and valve seats, perhaps even cylinder heads and pistons and/or piston rings . Harder to believe that fuel quality would result in failures of the long engine.....the conrods, the bearings or the crankshafts. it is possible though, if the fuel resulted in severe knocking of the engine during the firing cycle.

    As the war progressed, all the combatants put their engine types at greater and greater strains, as the very utmost in ppower was demanded of them. Hard to assume that any given design was any worse or better, although older or smaller engines may well have a lower initial design spec. I would however expect the allies to be in a better position overall, as their quality control and componentry were likley to have been better quality at wars end than either the axis or the Soviets.
     
  13. Jack_Hill

    Jack_Hill Member

    Joined:
    Mar 18, 2010
    Messages:
    192
    Likes Received:
    1
    Trophy Points:
    16
    Location:
    France
    #13 Jack_Hill, Jan 15, 2013
    Last edited: Jan 15, 2013
    And climat.
    Engines, air inducts, and cooling systems hates ingesting dust and much more, clouds of dust and small stones during dry, hot weathers.
    permanent snow is another factor.
    Inducing high percentage of water in the mix.
    "they didnt have too
    many good things to
    say about their
    practices. pilots got into
    planes, as soon as the
    engines were started
    they were immediately
    pushed to full throttle
    and the plane airborne.
    neither the pilots or
    ground crews did any
    pre-flight checks or
    engine warm up. the
    pilots took off in the
    direction the plane was
    facing at the time
    regradless of the wind
    direction ( cross wind,
    down wind..didnt
    matter) or placment of
    other ac. there was no
    co-ordination"
    Hi, Bobbysocks : So you already knows what it is biking along my helder brother !
    How can you know it ?
     
  14. Jabberwocky

    Jabberwocky Active Member

    Joined:
    Jul 24, 2005
    Messages:
    1,090
    Likes Received:
    16
    Trophy Points:
    38
    Occupation:
    Teacher
    Location:
    Japan
    Tante JU, this is very disengenious of you.

    1. The Merlins in the Russian Spitifres were neither new nor were they maintained to the same standards as in the UK. You have no idea how much time the engines had on them before they went to the Russians.
    2. The V-1710s in Russian P-40s experianced a similar situation
    3. You're using test flights made at high boost with 150 octane engines as representative of regular combat operations. Griffon 65s at +25lbs, Sabre IIs at +11 lbs, Merlins at +25 lbs. Put more stress on these engines and of course the failure rates are going to increase.
    4. You're pointing to specific examples and then generalising into a trend. This is dangerous territory.

    How about some engines in regular service, well maintained by the airforces of the country that built them? How about more than just a few individual examples?

    The R-2800 manual from 1942 suggest a conservative TBO of 350-400 hours. Rolls-Royce suggested a TBO of about 240 hours for the Merlin, but only around 30% of engines actually reached this figure. In service Packard V-1650s had a TBO of 110-180 hours in the Mustang in Nth Africa/Italy.

    An interesting read, if somewhat long, on the Axis History forum, from 2006. Kurfurst and Huck tried exactly this approach and see how far it got them:

    Axis History Forum • Reliability of aircraft engines
     
  15. CobberKane

    CobberKane Banned

    Joined:
    Apr 4, 2012
    Messages:
    706
    Likes Received:
    34
    Trophy Points:
    0
    When Eric Brown flew the La-7 at the war's end he described it as having excellent performance and handling, with the proviso that it did not appear designed to last as long as US and UK contemporaries. Anecdotally, the Soviets did not seem to expect their aircraft to last too long - a function of the strategic situation, I assume.
     
  16. Jack_Hill

    Jack_Hill Member

    Joined:
    Mar 18, 2010
    Messages:
    192
    Likes Received:
    1
    Trophy Points:
    16
    Location:
    France
    #16 Jack_Hill, Jan 15, 2013
    Last edited: Jan 15, 2013
  17. Shortround6

    Shortround6 Well-Known Member

    Joined:
    Jun 29, 2009
    Messages:
    9,773
    Likes Received:
    802
    Trophy Points:
    113
    Occupation:
    retired Firefighter
    Location:
    Central Florida Highlands
    Rolls was saying in 1939 that a fighter Merlin could go 240 hours and Bomber engine 300 hours. By 1944 they were saying 300 hours and in 1945 360 hours for the fighter engine. Bomber engine life was supposed to be 360 hours in 1944 and 420 hours in 1945. Even if we cut that to 60% for the average that would be 180 hours in 1944 for a fighter engine and 216 hours for a bomber engine. 3 1/2 to 4 times what is being bandied about.

    Modern light plane engines are good for around 1500-2000 hours for Continental and Lycoming engines. It is however, quite possible to have to replace a piston or cylinder well before reaching overhaul. FlyboyJ would know much better than I but running engines past their service life may be frowned on by the FAA no matter how good the oil looks.

    Once again these are suggested MAX lives, not money back guarantees. In peace time if the engines get a reputation for not lasting near what the "brochure" says the airframe company may start fitting a competitors engine. You can only exaggerate so much in your advertising before it blows up in your face.

    Great strides were made in metallurgy and testing during 6 years of war. Post war most of the R&D went into long life rather than power but it seems a bit strange that engines that could only give 50-60 hours of life in 1944/45 could give hundreds of hours of life if not over 1000 hours in post war airliner service. Not so strange if the engines were giving 400-600 hours in the last year of the war.
    Post war civil R-2800s were "rated" to use water injection for take-off, I have no idea how often they actually did it.
     
  18. Aozora

    Aozora Well-Known Member

    Joined:
    Dec 23, 2012
    Messages:
    1,011
    Likes Received:
    123
    Trophy Points:
    63
    #18 Aozora, Jan 15, 2013
    Last edited: Jan 15, 2013
    The quotes on the Merlin are, as suggested, disingenuous because the conditions under which they were run and the engine handling were all below the normal levels; this statement
    makes it quite clear that the engines were already well worn before reaching operations and had clearly not been serviced properly due to a lack of spares.

    1-Soviet Spitire V-page-001.jpg

    Another Russian opinion on the Merlin in the Hurricane:

    Part 1

    So, sure, I'll admit the average life of every Merlin engine built was about 50-60 hours after they had been worn out in operational service, subjected to more abuse during training and ferrying, then badly serviced because of a lack of manuals and spares. :lol:

    Allison in P-40

    Part 2

    P-39 (also left out)

    Part 3

    Guess the Russians had to learn some engine maintenance. :-\"
     
  19. davparlr

    davparlr Well-Known Member

    Joined:
    Mar 23, 2006
    Messages:
    2,934
    Likes Received:
    105
    Trophy Points:
    63
    Occupation:
    retired avionics engineer
    Location:
    Southern California
    Military pilots, while respectful, for the most part, of their aircraft and operate them within limitations under normal circumstances, have no compulsion against pushing performance past specs if they feel it is necessary for an important or vital maneuver. Fighter aircraft are often reported as over "g" ed and I am sure engines are over stressed as often. Maintenance activity are based on assumed operational environment and maintenance guarantees, like battle strategy, last only until the first shot is fired.
     
  20. bobbysocks

    bobbysocks Well-Known Member

    Joined:
    Feb 28, 2010
    Messages:
    3,811
    Likes Received:
    181
    Trophy Points:
    63
    Location:
    Pennsylvania
    #20 bobbysocks, Jan 16, 2013
    Last edited: Jan 16, 2013
    and because of that would the airframes have been considered "war weary" long before the engines ( generally ) were in need of overhaul? did they ever "overhaul" an engine? with production going full tilt would they have wasted the time and effort on rebuilding an engine from the crank up or just throw that one in the junk pile and do a complete engine change?

    and why does the last word in the first line sometimes get repeated??? lol

    i do not understand what you are asking me, jack. how do i know what? what i posted?
     
Loading...
Similar Threads
  1. Lucky13
    Replies:
    14
    Views:
    791
  2. Trebor
    Replies:
    2
    Views:
    1,445
  3. varing
    Replies:
    11
    Views:
    7,932
  4. Lucky13
    Replies:
    16
    Views:
    3,396
  5. marshall
    Replies:
    47
    Views:
    8,377

Share This Page