DCS: Spitfire Mk LF IXc Discussion

[BlackLion213]

That's to bad, for a second I had hopes for a potential north Africa setting with the P-40F, Spit V and maybe some day.. a 109F/190A

 

In addition to the VEAO map mentioned above, VEAO also plans a FW190A-8/F-8 and Bf 109E. The FW190A-8 was developed after North African operations (used in Italy IIRC), but the Bf 109E Trop was certainly used in North Africa, along with the Bf 109F.

 

The Spitfire IX was also used quite a bit, both by the RAF and USAAF. Between the Spitfire, P-40F, planned North Africa Map, and planned Bf 109 - there is good hope for North African Combat operations. :D

 

-Nick

[Kurfürst]

http://www.wwiiaircraftperformance.org/150grade/150-grade-fuel.html

 

By the time the K4 was introduced into service, the 2nd tactical airforce was using 150 octane fuel. And only 1 Canadian wing reverted back to 100/130 to perform aerobatics over defeated Germany.

 

Nope, they began planning and accumulating fuel for storage in November 1944. The 2nd TAF did not use a single drop of 150 grade in 1944.

None of the Spitfire Squadrons on D-Day were using +25 lbs in service - out of the ca. 30-40 Squadrons, only 2 (No 1 and 165 Sqn) were using +25 for operational trials, and very briefly, for V-1 busting opertions, and reverted in the automn of 1944.

That 'only 1 Canadian Win that reverted' was appearantly also the only Wing we have evidence to have been using +25 lbs in March 1945. You could well say they that they all reverted. ;)

 

Actual consumption of 150 grade fuel in the 2nd TAF begun on the very end of January 1945, though the records for the changeover are mostly from February-March 1945.

So far there is only evidence of a 126 Wings changeover to 150 grade fuel, out of the 25-30 Spitfire IX/XVI Squadrons. There may or may have not been more, but the paper trail is missing.

Also IIRC the 1650-7 was not entirely the same as the Merlin 66.

 

If DCS wants to model a 126 Wing Spitfire IX at +25 lbs from March 1945, that's a totally valid choice, provided we allow for double standards and for a version completely ahistorical and atypical for 1944, since +25 was non existent in operational service at that time (as noted being limited to trials with two Squadrons, No. 1 and 165, which reverted to normal fuel after a couple of months and encountered some early backfiring troubles), and given that all other present prop jobs are "normal boost" versions. Its also an odd choice given that the P-51D was operating on 72" and and the K-4 on 1.98ata by that time, not the present 67" and 1.8" as present.

Edited June 22, 2015 by Kurfürst

[GrapeJam]

Source please? So far all we've seen from you is assumption, more assumption.

 

Also you really like to push date, don't you?

Edited June 22, 2015 by GrapeJam

[Sporg]

The clipped wings Spitfire IX will still outturn any German planes that is not earlier than the 109E. The increase in turn radius over the normal wings version was very negligible, only 55 feet, and it actually had superior turn rate, especially in a climbing turn.

 

A comment I read about the LF Spitfire VB with clipped wings, the clipped wings made it inferior to the German fighters in turn fights, thus my comment.

 

I think you will find that the LF refers to the engine used, Merlin 66, not the type of wing tip.

 

Thank you for the correction.

I thought the LF designation was for a special low altitude engine, like in the LF Spitfire VB, where performance was very hampered at higher altitudes.

 

Then it would be fine with just an option for clipped or non-clipped wings if possible.

Both options available in one module would actually be super. :)

Edited June 22, 2015 by Sporg

[MiloMorai]

I thought the LF designation was for a special low altitude engine, like in the LF Spitfire VB, where performance was very hampered at higher altitudes./QUOTE]

 

There was no 'LF' designation for the Mk V. All had the designation 'F'.

 

http://www.airhistory.org.uk/spitfire/contracts.html

[Kurfürst]

Source please? So far all we've seen from you is assumption, more assumption.

 

Also you really like to push date, don't you?

 

1. Original estimate for 2nd TAF's requirement (for the future) 15000 tons per month, that is, end of november 1944, see: http://www.wwiiaircraftperformance.org/150grade/100-150_Grade_Supply_23Nov44.pdf

"Current requirements of 150 grade fuel and confined to the United Kingdom" - > no use of 150 grade and higher boost on the continent for the 2nd TAF as of end of November 1944.

"As matters currently stand, the only organisation which will use 150 grade on the Continent is the 2nd TAF" - note future tense.

 

2. Actual consumption: http://www.wwiiaircraftperformance.org/150grade/theater_barrels_tons.html

 

Consumption of 150 grade being 0 in 1944 for NW Europe (=2nd TAF).

 

Then 2-2500 tons in January/February 1945, 7000 in March 1945, 12000 in April 1945 -> 150 grade / +25 lbs slowly being introduced from January 1945. Full introduction presumably not until late March/April 1945.

 

Now present your evidence for widespread use of +25 lbs in Spitfire IX in 1944.

Edited June 22, 2015 by Kurfürst

[MiloMorai]

It is interesting that Kurfurst mentions paper trail and 1.98ata. In late Dec 1944, 1.98ata was trialed by a staffel of JG11 but wasn't cleared for operational use til ~6 weeks before the war in Europe ended. There is no evidence that 1.98ata was ever used operationally in those 6 weeks unlike for 150/25lb boost used by the Spitfire. There is only a fantasy order (that is, no original document has ever been produced) clearing 1.98ata for use.

 

25 lb boost was cleared for use in March 1944 (note: this is 12 months before 1.98ata was cleared for use in the Lw) and by Aug 12 1944, 16 squadrons had been converted to use 150/25lb boost. In Nov 1944, 25 squadrons of Spitfire IXs had been cleared to use 150/25lb boost.

 

What Kurfurst forgets is that those ADGB Spitfire squadrons were not sitting around on the ground waiting for Doodle Bugs to arrive over GB but were flying operational missions over the continent.

[gavagai]

I thought this thread was about the Spitfire.

[Kurfürst]

by Aug 12 1944, 16 squadrons had been converted to use 150/25lb boost.

 

Can you show something documenting this?

[Sporg]

I thought the LF designation was for a special low altitude engine, like in the LF Spitfire VB, where performance was very hampered at higher altitudes.

 

There was no 'LF' designation for the Mk V. All had the designation 'F'.

 

http://www.airhistory.org.uk/spitfire/contracts.html

 

If you go in deeper detail with your source, you will find for instance this page:

http://www.airhistory.org.uk/spitfire/p021.html

 

If you look at the details of serial "AR340" you will see that it is designated "LFVb"

 

Likewise the "AR327" and the "AR328" mentions a "LFLRVb".

The LFLRVb's are equipped with the 45M engine.

 

The performance of LF VB I checked in this page:

https://en.wikipedia.org/wiki/Supermarine_Spitfire_variants:_specifications,_performance_and_armament#cite_note-21

(This one listed with a 50M engine)

Note the altitudes for engine peak performance, top speed and max climb rate.

 

But I don't want to get into a longer discussion, others are probably stronger in the details than I am.

I was just afraid that we would get a plane that was only adapted to low level flying.

 

Thankfully it seems not to be the case. :)

Edited June 22, 2015 by Sporg
Error in quoting document for "AR337".

[GrapeJam]

Interesting enough I found this discussion....

http://forums.ubi.com/archive/index.php/t-245024.html

[Ala13_ManOWar]

Interesting enough I found this discussion....

http://forums.ubi.com/archive/index.php/t-245024.html

Yeah, 25lbs Spit has been a tough discussion in the pass over old sims. The problem with those old sims was the lack of real data use and absence of a platform capable of real hardcore simulations. BUT, while we only have three modules right now in DCS, I think ED has yet demonstrated enough they don't follow old arcadish paths, so IMHO any discussion about the aircraft is worthless until we have it. AND, I'm pretty sure even if we have the 25lbs variant it'll have it's RL performances and no more, so even with the 25lbs Dora will still be the best low level runner, and 109K4 will outperform the Spit easily mid and high altitudess like it does right now with P-51 (when you use them both correctly, of course :smilewink:).

 

S!

[Ala13_ManOWar]

Talking about performances, I was curious to know what means 25lbs manifold pressure, and it turns out corresponding roughly 51'' if I'm not mistaken. Can anybody confirm?

 

So having in consideration P-51 using a Packard roughly the same as Merlin but @67'' isn't a match for 109K4 I don't know why 51'' in a Spit would be any problem. You can give thanks we don't have Spit XVI using Packard engine... :lol:

 

S!

[Kurfürst]

+25 psi = 81" in US boost terms and something like 2,76 ata in German terms. ;)

[klem]

Talking about performances, I was curious to know what means 25lbs manifold pressure, and it turns out corresponding roughly 51'' if I'm not mistaken. Can anybody confirm?

 

So having in consideration P-51 using a Packard roughly the same as Merlin but @67'' isn't a match for 109K4 I don't know why 51'' in a Spit would be any problem. You can give thanks we don't have Spit XVI using Packard engine... :lol:

 

S!

 

25lbs means 25lbs above normal atmosphere (generically 14.7lbs @ S.L.), i.e. (25 + 14.7)/14.7 atmospheres = 39.7/14.7 = 2.7 ATA

 

And = 30" * 2.7 = 81"

 

With the right fuel P-51Ds/Packard Merlin could go to 75" and possibly more ( http://www.wwiiaircraftperformance.org/mustang/mustangtest.html as we're talking sources).

 

Back to the MkVb / LF MkVb they used different versions of the Merlin 45, the LF using the 45M and known as "Clipped"(wings), "Cropped"(Supercharger) and "Clapped"( probably the pilots' opinion?). Just one source of many:

https://en.wikipedia.org/wiki/List_of_Rolls-Royce_Merlin_variants

The LF was intended to combat the FW190 but it still couldn't really do the job until the MkIX came along.

 

Fortunately ED will do heir own research and hopefully we'll avoid the acrimony of 'another place'. Not that the MkVb is in the frame yet.

[GrapeJam]

25lbs boost is equal to 81"hg of manifold pressure.

[Cripple]

I thought this thread was about the Spitfire.

 

+1

 

Also, this thread seems to be getting a teeny wee bit "rivet-counting" in tone for my liking. Historical authenticity only goes so far when you are sitting in front of a PC going "weeeeeee-dakka-dakka-dakka". For all the empahasis on sim-pits and leather flying helmets (must get me one...), it's still a *simulation* - not a replication of historical events.

 

I'm all for a more appropriate WW2 map, either France or North Africa. However, so long as there is a degree of balance on the servers, I'm not too fussed which mark of plane squares up against which other one. I think there are more important details to focus upon, particularly as this seems to be the only combat sim currently focusing on them. :)

[Ala13_ManOWar]

Ooookkk, I see, so it's 25lbs over atmosphere and you have to add 1atm. Thanks mates ;).

 

 

So roughly 81'' seems a lot... I see also in reports linked a Mustang III saying he used +25lbs :shocking: . But in theory P-51 handbook states overboost is useless under a certain altitude (if I recall 14000ft?). If it's 81'' but still 3000 revs at low level, would it be any huge gain in performance without damaging the engine?

 

S!

[klem]

Ooookkk, I see, so it's 25lbs over atmosphere and you have to add 1atm. Thanks mates ;).

 

 

So roughly 81'' seems a lot... I see also in reports linked a Mustang III saying he used +25lbs :shocking: . But in theory P-51 handbook states overboost is useless under a certain altitude (if I recall 14000ft?). If it's 81'' but still 3000 revs at low level, would it be any huge gain in performance without damaging the engine?

 

S!

 

The Mustang III was an RAF version (NA called it the P-51C) so lbs instead of inches. Max boost and rpm was time restricted, 5 mins IIRC.

 

Putting my box of rivets away now. :P

[Solty]

Ooookkk, I see, so it's 25lbs over atmosphere and you have to add 1atm. Thanks mates ;).

 

 

So roughly 81'' seems a lot... I see also in reports linked a Mustang III saying he used +25lbs :shocking: . But in theory P-51 handbook states overboost is useless under a certain altitude (if I recall 14000ft?). If it's 81'' but still 3000 revs at low level, would it be any huge gain in performance without damaging the engine?

 

S!

The P-51B primarely had V-1650-3 which is based on Merlin 63. Thats why some book could state that WEP works only above some level. The Merlin 66 (V-1650-7) had improved low level performance, and it is quite clear that with WEP it was faster than without it.

[Solty]

Nope, they began planning and accumulating fuel for storage in November 1944. The 2nd TAF did not use a single drop of 150 grade in 1944.

None of the Spitfire Squadrons on D-Day were using +25 lbs in service - out of the ca. 30-40 Squadrons, only 2 (No 1 and 165 Sqn) were using +25 for operational trials, and very briefly, for V-1 busting opertions, and reverted in the automn of 1944.

That 'only 1 Canadian Win that reverted' was appearantly also the only Wing we have evidence to have been using +25 lbs in March 1945. You could well say they that they all reverted. ;)

 

Actual consumption of 150 grade fuel in the 2nd TAF begun on the very end of January 1945, though the records for the changeover are mostly from February-March 1945.

So far there is only evidence of a 126 Wings changeover to 150 grade fuel, out of the 25-30 Spitfire IX/XVI Squadrons. There may or may have not been more, but the paper trail is missing.

Also IIRC the 1650-7 was not entirely the same as the Merlin 66.

 

If DCS wants to model a 126 Wing Spitfire IX at +25 lbs from March 1945, that's a totally valid choice, provided we allow for double standards and for a version completely ahistorical and atypical for 1944, since +25 was non existent in operational service at that time (as noted being limited to trials with two Squadrons, No. 1 and 165, which reverted to normal fuel after a couple of months and encountered some early backfiring troubles), and given that all other present prop jobs are "normal boost" versions. Its also an odd choice given that the P-51D was operating on 72" and and the K-4 on 1.98ata by that time, not the present 67" and 1.8" as present.

 

 

You want to use numbers to disprove that Spit with 25lbs should be in game, even though there are reports of 25lbs Spitfires from mid 1944, while at the same time we have a Bf109K4 that barely made it to be in 1944 and was never formed into one squadron, but rather was treated as replacement for lost G6 and G14 etc. planes. So yeah... you spoke about double standards?

 

25lbs Spits still won't be as fast as Bf109K4 at most altitudes. I for one very much want 25lbs. Why? Because, not only is it historical, but also it gives so much needed balance in the matchup. Thanks to that Spitfire will not be a turkey and opens even more clearly historical power rating for P-51D.

[Kurfürst]

You want others to disprove something that you cannot prove in the first place - that's not how it works - so it appears that it needs to be cleared up again that there weren't any widespread or in any sense standard use of +25 lbs on Spitfire IXs at all in 1944.

 

The 'use' of +25 lbs was limited to just two Spitfire IX units, No. 1 and No. 165 Squadrons, i.e. 30-40 planes (with reserves - RAF Squadrons usually had a total of 20-22 planes, with 12/13 flyling and the rest being reserves) at best, out of 1000 or so IXLFs and even these two Squadrons were just there for doing trials to gain experience and fix defects like backfires, plug fouling etc. with the new boost and fuel. In the meanwhile, 95% of all the standard Spitfire IXs Squadrons in the ADFU and in the 2nd TAF, and everywhere else in the world at the same time were still using the standard +18 lbs boost or less.

 

So what you wish for in fact is a very very rare bird in experimental stage.

 

And although the 109K is not the subject of this thread, it appears you are ill-informed in thats plane operational use as well (see comments like never formed a Squadron etc.) - see the TOE for III/JG 77 for example, I see 75 109Ks arriving in October 1944, all the remaining G-14s being transferred to other units, making it a 'pure' *(and actually overstrenght) 109K Wing, with 4 full Squadrons of 109Ks. Or there is III. Wing of JG 26, with four Squadrons in total, which had 36 G-14s and 35 K-4s. Unless you are suggesting otherwise, I am going to presume the logical thing, that is that they were split up in the Wing as 2 Squadron of G-14s and 2 Squadron of K-4.

 

I kinda agree about the balance thing, but since ED's stance so far was to have the most common/basic variant for 1944, I do not see why an exception would need to made with the Spit IX. That's why we have the P-51D with 67" and not 72" boost (although I think we should). That's why we have the 109K with 1.8ata and not 1.98ata boost (since it wasn't present yet in meaningful numbers in 1944, just as the IX at +25 lbs wasn't).

 

The IX will be slow anyway, but will still easily outturn everybody else and climb very well. Nothing of that will change with +25 lbs either, except that Spitfire fanboys won't get the 'bestest' and rarest variant they always seem to wish for.

Edited June 23, 2015 by Kurfürst

[Sporg]

Back to the MkVb / LF MkVb they used different versions of the Merlin 45, the LF using the 45M and known as "Clipped"(wings), "Cropped"(Supercharger) and "Clapped"( probably the pilots' opinion?). Just one source of many:

https://en.wikipedia.org/wiki/List_of_Rolls-Royce_Merlin_variants

The LF was intended to combat the FW190 but it still couldn't really do the job until the MkIX came along.

 

It's funny, it is that exact quote I was thinking of: "Clipped, Cropped and Clapped".

 

I read it in P. Clostermanns "The Big Show". a book that has been my companion for many years, and the base for my interest in WW II fighters.

 

According to him, the reason for the pilots' animosity towards the Spitfire LF Vb was that it was very optimized for low level flight, where it was very fast and had high climb rate.

However, due to the cropped compressor, the engine power curve fell sharply with altitude, so that at 12000 feet it had on 500 Hp(!).

Add to that that they got worn out airframes, and were told to do high altitude long range bomber escort for a while before they could get more modern fighters.

Not a popular combination. ;)

 

Regarding the discussion about how many Bf 109 K4's were available in mid 1944, it is interesting to see P. Clostermanns opinion:

According to a 1964 report from Allied historical services which he read after the war, one Jagdgeschwader, JG-300, in July 1944 had no less than approximately 100 FW 190 A8s or D9s available, together with around 90 Bf 109 K.

 

To me that doesn't sound like the 109 K was such a rare airplane that some people in here claim it to be?

 

Anyway, I still look forward to the Spitfire Mark IX. :)

Edited June 23, 2015 by Sporg

[Rangi]

 

I kinda agree about the balance thing, but since ED's stance so far was to have the most common/basic variant for 1944, I do not see why an exception would need to made with the Spit IX.

 

 

I think ( I don't know), that ED's stance so far is to have the variants that they have the best information on, not necessarily the most common. So if they do a 25lbs boost Spit IX it's because they have the best information on that. Has it been confirmed which boost we will be getting?

Edited June 23, 2015 by Rangi

[Ala13_ManOWar]

It's funny, it is that exact quote I was thinking of: "Clipped, Cropped and Clapped".

 

I read it in P. Clostermanns "The Big Show". a book that has been my companion for many years, and the base for my interest in WW II fighters.

 

According to him, the reason for the pilots' animosity towards the Spitfire LF Vb was that it was very optimized for low level flight, where it was very fast and had high climb rate.

However, due to the cropped compressor, the engine power curve fell sharply with altitude, so that at 12000 feet it had on 500 Hp(!).

Add to that that they got worn out airframes, and were told to do high altitude long range bomber escort for a while before they could get more modern fighters.

Not a popular combination.

 

Regarding the discussion about how many Bf 109 K4's were available in mid 1944, it is interesting to see P. Clostermanns opinion:

According to a 1964 report from Allied historical services which he read after the war, one Jagdgeschwader, JG-300, in July 1944 had no less than approximately 100 FW 190 A8s or D9s available, together with around 90 Bf 109 K.

 

To me that doesn't sound like the 109 K was such a rare airplane that some people in here claim it to be?

 

Anyway, I still look forward to the Spitfire Mark IX.

I wouldn't rely on any Clostermann's statements for accuracy. He's a very well known storyteller... He just wrote an adventures novel, not a history book, and you know novels don't have to be any accurate at all. So if he talks about the biggest and mightiest Luftwaffe in front of himself alone just to appear as the big pilot he wasn't is a novelist mind only.

 

S!

Edited June 23, 2015 by Ala13_ManOWar