P51D vs Spitfire MkXIV (14)

[niklas]

Nashwan, in the introduction of the tactitcal comparison it is clearly mentioned that the Spit9 was going with +18 boost and 3000rpm.
You know yourself why some spits shine in some Boscomb test, donīt you ? This is from you:
 

The reason I now doubt the 408mph figure is because of a quote from Jeffery Quill regarding Spitfire testing. It's on the Fourth Fighter Group page.
"As time went on Boscombe Down came increasingly to accept the firms figures, making only spot checks themselves, in order to save wear and tear on the prototypes. In other words Boscombe Down provided the offical seal of approval, though many of the performance figures quoted in their reports were in fact measured by Supermarine's experimental flight test unit at Worthy Point, later at Hight Point. The A and AEE made their own judgements on the aircraft's handling and other qualities."

( http://www.hitechcreations.com/cgi-bin/ultimatebb.cgi?ubb=get_topic&f=9&t=000524)


Karnak: If you reed the report with the performances of the Spit14 carefully, you ll find the following line:
"It is understood that the final version of the Mk.XIV will have a Griffon 65 engine which differs from the engine now installed in having a higher MS supercharger gear ratio"
When you change in the 2nd. gear, you lose power. If you reduce a gear ratio, you gain power logically.
We donīt know how much power the Spit had at sealevel, BUT we know it from the 2nd gear, around 1800hp, right?
The difference in climbrate is 5100-3600 = 1500ft/min.
To lift 8400lb with another 1500ft/min, you need ~450hp.
Itīs easy to see that the Spit must have had more than 2200hp near ground. http://www.unlimitedexcitement.com/Griffon%20Budweiser/Griffon%20Engine.htm
this page has listed at nr.85 a griffon with 2350hp and the same low critical altitude (1250ft)

niklas

[ 11-21-2001: Message edited by: niklas ]

[Vermillion]

I'm going to say it again, and the Spit lovers will burn me at the stake   but here goes.

The British equivalent in late 1944 and 1945 to the P-51D was the Spit IX (1944 varient). Not the Spit XIV.  Just take a look at the production numbers as too which was the "important" (most prevalent) fighter to the British government. IE thats where they concentrated their production efforts.

In my opinon (and I'm sure to be toasted here too), if you want the American equivalent to the Spit XIV for comparison purposes, you would point to the F4U-4, the P-47 M/N, the P-51H, and maybe the Bearcat.

The reason is that the Americans knew they were already winning the war thru superior production, and a war of attrition. They didn't want to disturb production numbers by having to retool the lines.  The British obviously had the same theory, since they concentrated on the production of the IX, however they did expend some effort to higher performance aircraft, and produced fairly limited numbers of the XIV. Just like the P-51H was planned for production, but the Germans colapsed prior to that need.

There was a very similar strategy that the Americans used for Tank production.  I have read that the Pershing heavy tank could have been in production before D-Day, but the higher echelons decided it was better to have large numbers of Shermans, and to have less Pershings (only a handful in the last days of combat).  Something that alot of US tank crews paid for in blood. But the strategy DID work.

So I guess my point is this. If your gonna play the "my noodle is bigger than your noodle" game, by comparing which country had better fighters, lets compare apples to apples.  

*dons asbestos suit*

Ok boys, come get me  

*battens down the hatchs on the blast shelter*

[Pongo]

If the Spit XIV is modeled as a Spit IX with speed in the range of a Pony and Climb in the range of a G10...It will be a monster.
It will be more usefull then a tempest. 100 point perk...

[Karnak]

Pongo,

If the Spit XIV is modeled like a Spit IX with the speed of a P-51 it'll be modeled wrong.

The Spit XIV was slower than the P-51 until it was over 24,000ft.

The fact that there are so many free aircraft that are faster than it means that it would have very low survivability in the MA with a "Spit14", e.g. "come kill me", icon over it.  The La-7, Fw190D-9, Typhoon, P-51D, P-51B and Bf109G-10 are all faster than it.  Two of those, the P-51D and La-7, are VERY common.  Either the Spitfire XIV would stay up in the stratosphere, like the Ta152H-1, or the player would pretty much be throwing 100 perk points away.

The perk system is intended to control aircraft that would be too dominant if free, not eliminate them.  At 30 points you wont see Spit 14s all over the place, but you will occasionally see them.  At 100 points you would practically never see them.

Vermillion,

You are correct about which Spitfire was the main strength of the RAF in 1944.

However, do you see HTC modeling a second Spitfire MkIX?  The one we have is, except for armament options, a 1942 Spitfire MkIX.

I would also point out that the main strength of the Luftwaffe was Bf109G-6s and Fw190As, however in AH by far the most common are the Fw190D-9 and Bf109G-10.  What was true historically is not alwasy true in AH, to say the least.

Gatt,

The Spitfire XIV has to be a perk plane.  It is simply too well suited to the MA otherwise.  Fully 33% of the sorties would probably be Spitfire XIV sorties if it weren't perked.

Disclaimer: I fly RAF aircraft about 66% of the time.  

[GRUNHERZ]

Karnak many of the G6s by early-mid 1944 were either G6AS with performance near that of G10, still others were G6AMs with MW50, and other G6s mounted GM1 for extra high alt performance. Our G6 is a plain February 1943 version in performance although it does mount the erla haube which began appearing in autumn of 1943. In other words it is a damn near contemporary of your late 1942 spit fIX.

[GRUNHERZ]

Verm the pershing story is quite a bit more complicated than that, but certainly a tragedy.

[Seeker]

I'll take a Spit IX over a P-51 over any situation where I've got enough gas. Hell, I'll take a Spit V!

One thing the yanks never understood (and it shows in their "sports" cars") is the distinction between power and the application of that power.

Take a Vette and a Aston DB 6 for instance. Who really would choose the over powered under developed plastic fantastic instead of a real mans car?

<sets rod, opens up the lunch box and waits....>

[Karnak]

GRUNHERZ,

Er, that would make the AH Bf109G-6 a near contemorary of the Spitfire LF.MkIX that entered service in March, 1943, not the June, 1942 Spitfire F.MkIX that we have in AH.  

[38isPorked]

"Fully 33% of the sorties would probably be Spitfire XIV sorties if it weren't perked."

You mean 66% right? The 33% that fly the old spits now will hop on along with the sissyfire cheerleaders on to the new spit.

 

[funkedup]

F4U-4, the P-47 M/N, the P-51H, and maybe the Bearcat.

Ridiculous Verm.  Spitfire XIV was in squadron combat service from Jan 44 and saw widespread service in the ETO after that.  None of those aircraft you mention were introduced anywhere near that early or had the same kind of combat record.  Spit XIV was in full production and combat months before bubble canopy P-47D or P-51D made it into battle.

The Brits built 957 Mk. XIV.  If production of XIV was less than it could have been because the Griffon engines were needed for the even faster Mk. XIX, Mk. 21, and Seafire 45 which were coming into production by the Fall of 1944.  Those marks are the ones that are comparable to the ultra-late-war US planes you mention.

[ 11-21-2001: Message edited by: funkedup ]

[Karnak]

I would agree with Funkedup on that point.

The Spitfire that would compare with the F4U-4, the P-47 M/N, the P-51H, and maybe the Bearcat would be the Spitfire F.21.

There isn't any direct comparison, that I can think of, of a US aircraft with the role the Spitfire XIV played in the RAF.  I'd say that the best comparison of other nation's aircraft would be the La-7, Bf109K-4 and Fw190D-9.

[Karnak]

38,

I think you'll find that the Spitfire MkIX scored 9.25% of the kills in the MA this tour.  That is far below the 33% that you claimed, and actually significantly lower than the 15% I was going to guess.

One of the reasons that people hate the Spitfire so much in AH is because numbers like that are thrown about and people believe them.  Beliving them, they remeber seeing a lot of Spitfires and forget about the P-51s, Yaks, 109s and 190s that they also saw.

[Nashwan]

Niklas, you seem to have quoted me totaly out of context. My quote from above was a first paragraph, and then went on to ask if the manufacturers tests had been of an early variant running only 15lb boost.
It turns out that was the case. Test I have seen of later Spits, running 18lb boost, give higher performance figures than you are quoting. Could you point me to a link for the tactical comparison you are quoting?

You seem to be insinuating the Spit performance claims aren't valid because they may have been done by the manufacturers, before being independantly verified.
You have recently posted a speed chart for the 190A5 done by FW, with no verification, and expect that to hold weight?

 

Though the tactical trials again carefully avoid to mention absolut performance numbers, it is possible to estimate at least the sea level speeds.

Beginning with the FW-190, where we known that it did ~335mp/h near ground in english tests:
FW-190 (335mph / 540km/h)
Spit-14 +20 mph = 355mph (570km/h) - definitly not a speed king imo
P51-III +20 = 355 mph (570km/h) very interesting, VERY interesting
Temp V +40 = 375 mph (605km/h)
Spit9 - 15 = 320 mph (515km/h) with +18
109G - 20 = 315mph (505km/h)

Carefull to avoid exact performance figures?
You are calculating rough performance figures from a tactical comparisson, which isn't intended to provide exact figures, and then want those rough calculations to be taken as more representitive than the real  performance tests?

 

To lift 8400lb with another 1500ft/min, you need ~450hp.
Itīs easy to see that the Spit must have had more than 2200hp near ground. http://www.unlimitedexcitement.com/Griffon%20Budweiser/Griffon%20Engine.htm  
this page has listed at nr.85 a griffon with 2350hp and the same low critical altitude (1250ft)

That's running at 25lb boost. Read the performance figures for the Spit XIV test, and you will see it's limited to a max of 18lb boost. That's why they fitted automatic boost control to the Spits, to stop them running too much boost at low altitudes. It doesn't matter what the supercharger could deliver, 18lb is all it was allowed to deliver.
Tell me how you can get an extra few hundred HP out of the Griffon without increasing the boost. The RR engineers must be kicking themselves they didn't think of it during the war.

 

posted 11-21-2001 09:32 AM                
--------------------------------------------------------------------------------
I'm going to say it again, and the Spit lovers will burn me at the stake  but here goes.
The British equivalent in late 1944 and 1945 to the P-51D was the Spit IX (1944 varient). Not the Spit XIV. Just take a look at the production numbers as too which was the "important" (most prevalent) fighter to the British government. IE thats where they concentrated their production efforts.

In my opinon (and I'm sure to be toasted here too), if you want the American equivalent to the Spit XIV for comparison purposes, you would point to the F4U-4, the P-47 M/N, the P-51H, and maybe the Bearcat.
Vermillion

As funked an Karnak said. One extra point though, you say production effort. The US produced more than 3 times as many aircraft as Britain during 44. That means as a proportion of production effort, those 957 Spit XIVs are equivalent to more than 3000 US fighters. Far more important than the Bearcat, P47M/N and P-51H combined, and off the scale with the numbers of those aircraft produced in 1944.
As a proportion of "production effort", the Spit XIV was more important than the US fighters you mention, but also the 190D9, and probably the 109K4 (I don't know how many of those were produced)

Regardless, I'd be happy with a perked Spit XIV, but I have yet to see any justification other than play-balancing for the abscence of a later version of the Spit IX, ie one of the 5000+ (6000+ if you include the XVI) rather than one of the first, worst, 350.

[Tony Williams]

Originally posted by R4M:


Maybe in hitting power ,but you MUST hit with it.

50cal had a better RoF than Hispano
50cals in Stang had WAY more ammo per gun than spit's hispanos.
And finally, there were SIX 50 cals for TWO hispanos.

You never kill what you never hit   . I still think the P51D had WAY better weapons than the spit.

From my next book (with Emmanuel Gustin):

"The kill probability of a 2.5 second burst from a quartet of Hispano Mk II was quoted as 80% at 275 m and 60% at 365 m."

You can work out what it would be with two cannon.  The .50s needed LOTS more hits to kill a plane, as attested by the number of German fighters which returned safely to base despite being damaged in action against US bomber formations.

Comparison of the 20mm SAPI with the .50 M8 API is instructive.  The M8 had a hard core with about 1 gram of incendiary material in the tip.  The SAPI was a cannon shell with a hard cap.  It could penetrate about the same as the M8 (15-20mm armour) but contained 11 grams of incendiary material - yep, eleven times as much.  The 20mm HEI contained the same amount of Pentolite or Tetryl.  In destructive ability it was in a different league from the .50

Tony Williams
Author: "Rapid Fire: The development of automatic cannon, heavy machine guns and their ammunition for armies, navies and air forces"
Details on my military gun and ammunition website:
PLEASE NOTE CHANGE OF ADDRESS http://website.lineone.net/~a_g_williams/index.htm
Military gun and ammunition discussion forum: http://www.delphi.com/autogun/messages

[niklas]

Hi Nashwan
 

Niklas, you seem to have quoted me totaly out of context.... Could you point me to a link for the tactical comparison you are quoting?

I only wanted to know whether you can remember yourself to that info. When you compare the performance gain of a spit9 with +18lb compared to +15lb, then itīs quite obvious that it wasnīt alone a power raise that brought the given performance increases....
For the link just follow Karnaks first link in this threat and read the first lines again. It clearly mentions a spit9 with +18lb

 

You have recently posted a speed chart for the 190A5 done by FW, with no verification, and expect that to hold weight?

this is not true, i said itīs a performance calculation from the department of flight mechanics in the other thread. I didnīt started the "our 190a5 is too slow" threat btw.
 
 

You are calculating rough performance figures from a tactical comparisson, which isn't intended to provide exact figures, and then want those rough calculations to be taken as more representitive than the real performance tests?

Well, first i have to say: What is a report worth where aircrafts are compared without mentioning the exact weight, aircraft condition, power setting etc.??? NOTHING!

Nevertheless the speeds from my simple calculation are not unrealistic. It wasnīt me who found out the speed differences. Fact is:
There doesnīt exist a 190A in english reports which did more than 340mph near ground afaik. So when the Spit14 did more than 355-360mph, why didnīt they mention this 190A in reports?
The speed of the MustangIII is very realistic.
When the tempest is in climbrate not in "the same class" as the spit14, then it didnīt have the same power as our tempest in AH. That means 2240hp maybe. When the spit14 was much faster than 355mph, then the tempest would have done 390-400mph near ground...with 2250hp - unrealistic
They mention that the spit14 will be as fast as a new 190D with DB603 engine. This is very interesting. Obviously they had information about the german tests. I have the test of the dora with DB603A engine (1750hp), and the speed near ground was...:572km/h, 355mph

How much more proof do you need?

About the other spitfire with 5100ft/min climbrate.
Whenever +25lb was used, it was mentioned in the page. Donīt forget that the other engines with +25lb put out ~2500hp with larger supercharges AND higher gear ratios.

How do you explain the climbrate difference of 1500ft/min??

I give you another hint: If you interpolate the curve from the 2nd gear down to sealevel, youīll end at approximatly 335mph.
Speed increases approximatly with a funcion of (power ratio)^1/3
So:
(362/335)^3 = 1,26
1,26*1800hp = 2270hp

The speed difference AND the climb rate difference indicate both that the spit had probably ~2250hp in this test near ground

niklas