1. #51
    Originally posted by Kurfurst__:
    <BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by The-Pizza-Man:
    <BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Kurfurst__:
    <BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by The-Pizza-Man:
    Kurfurst, read the documents fully. You've neglected the reserve fuel allowance, which is 23-25 gal. This gives an MPG of 7.6 to 7.8 when averaged with take off and climb. Figures of 8-9 MPG for cruising are not unreasonable.
    The fuel allowance is noted to be reserved for takeoff (ie. taxy, warmup, take off run) and climb.
    </div></BLOCKQUOTE>

    Nevertheless, MPG is still greater than you originally thought. </div></BLOCKQUOTE>

    It is not. You're comparing apples to oranges. The MPG for the whole trip (takeoff, climb, cruise) is lower than the MPG under the most economic cruise conditions alone. There's nothing amazing in that.
    </div></BLOCKQUOTE>
    Actually you were comparing apples with oranges, I was just correcting you.

    Aren't these figures from your previous post

    Mk IXF (Merlin 61) : 450 miles / 85 gallons = 5,29 mpg on avarage
    Mk IXLF (Merlin 66) : 434 miles / 85 gallons = 5,10 mpg on avarage
    Mk XVI (Merlin 266) : 434 miles / 85 gallons = 5,10 mpg on avarage
    Mk VIII (Merlin 66) : 740 miles / 120 gals. = 6.16 mpg on avarage
    These are "MPG for the whole trip", which you were comparing with MPG during cruise, the 10 MPG from the Australian tests. I just provided the rough MPG from the data sheets.
    <BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Not to be nit picking, but the Merlin spits would climb at a lower speed than Griffon engine spits because of their lower wing loading and would thus cover less distance in the climb. The difference in climb speed is probably 10-20 mph.
    Which would lead to 1-2 miles difference covered in climb, if what you're saying is true. </div></BLOCKQUOTE>

    Which it is.
    <BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">I still think that 8-9 MPG is reasonable from a well maintained aircraft.
    You're welcome to be entitled to your opinion, RAF datasheets however clearly and consistently show they've calculated with ca. 6.5 mp for Mk IX, and ca. 7.3 mpg on cruise for the Mk VIII with extended wingtips in the range tables. I'll stick to the hard data instead of assumptions. </div></BLOCKQUOTE>


    The fact that "hard data" such as the 10 MPG was achieved under test conditions with a drop tank is enough to suggest that 8-9 is possible. Range tables may be conservative so as to account for the bottom 10% of aircraft that weren't as fuel as efficient as the majority of aircraft.
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  2. #52
    Dear Pizza Man,

    Feel free to ignore the mass of RAF's datasheets and be entitled to your position. You may have missed that one below for example http://i38.photobucket.com/albums/e1..._milleage2.jpg

    OTOH the whole question of mileage is rather irreveleant, since both the RAF and RAAF gives consistent ranges of 434-450 miles for Mk IXs on 85 gallons and 740 miles for Mk VIII on 120. Whatever the mileage was, that was their maximum range, unless one claims he knows better than the RAF..
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  3. #53
    Originally posted by faustnik:
    I have a simple reality chart:

    <span class="ev_code_BLUE">Kurfurst's Spitfire</span> < Real Spitfire < <span class="ev_code_RED">Hopp's Spitfire</span>


    Amen
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  4. #54
    Xiolablu3's Avatar Senior Member
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    Originally posted by Kurfurst__:
    It's entirely their social problem if they don't like the figures the RAF rates it's own fighters
    I seem to remember you getting upset about Mike Williams using figures for the 109 from Messerschmitt AG because they werent that great.

    Therefore you dont like the way Messerschmitt rates its own planes either.
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  5. #55
    M8 if I step back and see the big picture I see a wagonload of RAF and RAAF documents all stating the same, and ONE RAAF tst saying something different.

    BTW if you're problem is that the Australian tests are being ignored, keep in mind that both performance and consumption tests were performed with the Mk VIII JF 934. The highest top speed measured was ~635 km/h. Again, that's the same plane from which the 10 mpg figure originates from.

    So, should we use JF 934 as representative, because if we do, we should use the performance figures obtained on it as well.

    As for Mike Willians, he seems to ignore tests from Messerschmitt AG as well, if they show high performance, but that's old story. Messerschmitt rated it's planes quite higher and Rechlin rated the planes quite higher and the datasheets issued by the LW Quartermeister rated the planes quite higher than Mike Williams seems to admit.
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  6. #56
    Originally posted by Kurfurst__:
    Dear Pizza Man,

    Feel free to ignore the mass of RAF's datasheets and be entitled to your position. You may have missed that one below for example http://i38.photobucket.com/albums/e1..._milleage2.jpg

    OTOH the whole question of mileage is rather irreveleant, since both the RAF and RAAF gives consistent ranges of 434-450 miles for Mk IXs on 85 gallons and 740 miles for Mk VIII on 120. Whatever the mileage was, that was their maximum range, unless one claims he knows better than the RAF..
    I never disputed the ranges. I only had a problem with you comparing mileages that were inconsistent with each other.
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  7. #57

    You guys are very knowledgeable!!

    Does anybody have any links for pictures of the JATO used on the Seafires? I’m diving off Southampton and I have found what seems to be a pair of rockets that have been jettisoned (as well as gas tanks) - it’d be interesting to see them before they’ve been underwater for 60/70 years! Apologies if this has been talked about already!

    They’re about 1.5meters long,
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