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View Full Version : Spitfire IX's speed down low question.



kyrule2
02-04-2004, 03:33 PM
I have read that the Spitfire XII with Griffon engine was designed and used (100 examples used for home defense) to counter the low-level raids by the FW-190 because the Spitfire IX had insufficient speed at low altitude, clipped or not. The quote finished by saying that this was the second time that the FW-190 had influenced Spitfire production.

I wonder what the Spit IX's speed at sea-level will be. It should be lower than the A-4 which is 540km/h, but that would mean that the A-5 would simply run away from it (570km/h) in '43. If they make it faster than the A-4 then it will contradict everything I have read concerning this. I'm very interested in seeing what they come up with in terms of Spit IX's speed down low.

So what should it be? I have seen top speeds for Mk.IX listed as 408 at 20+ thousand feet and 312 at sea-level. I wonder what the numbers are for LF. variants with clipped wings or if there is a significant difference at all?

http://www.brooksart.com/Icewarriors.jpg

"Ice Warriors" by Nicolas Trudgian

kyrule2
02-04-2004, 03:33 PM
I have read that the Spitfire XII with Griffon engine was designed and used (100 examples used for home defense) to counter the low-level raids by the FW-190 because the Spitfire IX had insufficient speed at low altitude, clipped or not. The quote finished by saying that this was the second time that the FW-190 had influenced Spitfire production.

I wonder what the Spit IX's speed at sea-level will be. It should be lower than the A-4 which is 540km/h, but that would mean that the A-5 would simply run away from it (570km/h) in '43. If they make it faster than the A-4 then it will contradict everything I have read concerning this. I'm very interested in seeing what they come up with in terms of Spit IX's speed down low.

So what should it be? I have seen top speeds for Mk.IX listed as 408 at 20+ thousand feet and 312 at sea-level. I wonder what the numbers are for LF. variants with clipped wings or if there is a significant difference at all?

http://www.brooksart.com/Icewarriors.jpg

"Ice Warriors" by Nicolas Trudgian

hop2002
02-04-2004, 04:29 PM
The first production Spit IX was the F IX with Merlin 61. Speed should be around 312 at sea level, but that's for a version with the bigger bulges on the wings for 4 20mm cannon, although only 2 20mm cannon were fitted.

In late 42 or early 43 most production switched over to the LF IX with Merlin 66, which developed considerably more power down low. Speed for that should be 335 mph /540 km/h at sea level, with full span wings.

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>It should be lower than the A-4 which is 540km/h,<HR></BLOCKQUOTE>

Only the first Spit F IXs should be slower at sea level, but I don't think we're getting one of those in FB. Approx 350 F IXs were built with the Merlin 61, around 4000 with the Merlin 66 (plus another 1,000+ of the almost identical Spit XVI with the Packard built Merlin 266).


<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR> but that would mean that the A-5 would simply run away from it (570km/h) in '43.<HR></BLOCKQUOTE>

That seems too fast for most A-5s. The US Navy did a test of an A5, and managed about 335 mph at sea level. The USAAF tested a G3 and got 341 mph.

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>I wonder what the numbers are for LF. variants with clipped wings or if there is a significant difference at all?

<HR></BLOCKQUOTE>

I don't know a reliable figure for the speed gain from clipping the wings. I've seen it put as low as 1 mph, and as high as 15 mph, but none of them are from reliable sources.

For Spitfire performance, go to

http://www.fourthfightergroup.com/eagles/spittest.html

DaBallz
02-04-2004, 06:52 PM
I remember the 15 mph figure, but I think
it was with the specially cropped supercharger
impeller, not just the clip job.

Spits were not great speedsters on the deck.
Jane's WWII Fighters got some believing a
Spit IX could stay with a D model P-51 down
low, that's nonsense. Even a Griffon engined
Spit would have trouble staying with a P-51
at sea level.

Da...

hop2002
02-04-2004, 07:51 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Spits were not great speedsters on the deck.
Jane's WWII Fighters got some believing a
Spit IX could stay with a D model P-51 down
low, that's nonsense. Even a Griffon engined
Spit would have trouble staying with a P-51
at sea level.
<HR></BLOCKQUOTE>

From mid 1944 onwards, it's not that far off the truth.

150 octane fuel allowed the Merlin 66, and the V-1650-7, which was essentially the same engine, to run at increased boost and power. Power went up to around 2000 hp at sea level, which is slightly more than the Griffon engined Spit XIV.

The USAAF didn't run their Mustangs at that high a power setting though, so they didn't see as much improvement as an RAF Spit did.

Speed for the Spit LF IX with 150 octane went up to around 360 mph at sea level, which is pretty close to what you could expect from a USAAF Mustang (probably around 370 or so)

Huckebein_FW
02-04-2004, 08:00 PM
For A5 max speed at sea level given in its manual is 560km/h.

http://home.comcast.net/~bogdandone/me262_steinhoff.jpg

SkyChimp
02-04-2004, 08:39 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Huckebein_FW:
For A5 max speed at sea level given in its manual is 560km/h.

http://home.comcast.net/~bogdandone/me262_steinhoff.jpg <HR></BLOCKQUOTE>

Advertising data. http://ubbxforums.ubi.com/infopop/emoticons/icon_biggrin.gif

Regards,
SkyChimp
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Huckebein_FW
02-04-2004, 08:45 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by SkyChimp:
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Huckebein_FW:
For A5 max speed at sea level given in its manual is 560km/h.

http://home.comcast.net/~bogdandone/me262_steinhoff.jpg <HR></BLOCKQUOTE>

Advertising data.
<HR></BLOCKQUOTE>

You're jealous Chimp, get over it http://ubbxforums.ubi.com/images/smiley/mockface.gif

http://home.comcast.net/~bogdandone/me262_steinhoff.jpg

SkyChimp
02-04-2004, 08:48 PM
You're on to me.

Regards,
SkyChimp
http://members.cox.net/rowlandparks/skychimp.jpg

DeerHunterUK
02-05-2004, 05:10 AM
I don't know if this is any help to you but the following is excerpts from the official trials report carried in July '42 between a Spitfire IX and a captured 190:

At 2,000 ft (610m) the FW 190 is 7-8mph (11-13km/hr) faster than the Spitfire IX.
At 5,000 ft (1,524m) the FW 190 and Spitfire IX are approximately the same.
At 8,000 ft (2,440m) the Spitfire IX is 8mph (13km/hr) faster than the FW 190.
At 15,000 ft (4,573m) the Spitfire IX is 5mph (8km/hr) faster than the FW 190.
At 18,000 ft (5,488m) the FW 190 is 3mph (5km/hr) faster than the Spitfire IX.
At 21,000 ft (6,400m) the FW 190 and Spitfire IX are approximately the same.
At 25,000 ft ( 7,622m) the Spitfire IX is 5-7mph (8-11 km/he) faster than the FW190.

In the conclusions section it states that the "Spitfire IX worst heights for fighting the FW 190 were between 18,000 and 22,000ft (5,486m and 6,707m) and below 3,000ft (914m)".

No1_Moggy
-----
In memory of 'The Few'
http://www.lima1.co.uk/Sharkey/spitfire.jpg
The Tangmere Pilots - http://www.tangmerepilots-raf.co.uk/
Know your enemy and know yourself; in a hundred battles, you will never be defeated.

blabla0001
02-05-2004, 05:28 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Huckebein_FW:
For A5 max speed at sea level given in its manual is 560km/h.<HR></BLOCKQUOTE>

That's only +/- 20 km/h faster then a Spitfire MK IX, whoop-die-dooo.

I don't see how this can pose a real problem since it will take some time to create a large enough gap to get out of reach of the Spitfires machine guns and cannons.

Bartsimpson-
02-05-2004, 06:58 AM
'Why' ????? you afraid your reign of b.n.z. and chicken run is about to come to an end .

Bart

hotspace
02-05-2004, 07:41 AM
In late June of 1944, Spifire MkXIV's were modified to counter the V-1 threat. They gave it a higher boost rating and 150 Gas making it's Top Speed of over 400 mph on the Deck http://ubbxforums.ubi.com/infopop/emoticons/icon_smile.gif

Just as fast as the Hawker Tempest Mk V.

Hot Space

http://img11.photobucket.com/albums/v33/Hot_Space/me1.jpg

VW-IceFire
02-05-2004, 07:49 AM
LF IX on the deck should be fast enough in the short to catch a FW190. In most cases the FW190 is going to pull away from most planes at low altitude eventually (except the La-7 and the Tempest V). The version were getting shouldn't have a pronounced effect.

There is a possibility that a earlier model of the IX will be modeled into FB. We'll have to see if that comes true or not...also a XVI.

http://home.cogeco.ca/~cczerneda/sigs/temp_sig1.jpg
The New IL2 Database is Coming Soon!

lrrp22
02-05-2004, 08:46 AM
Hot Space,

Here you go (couresy of the 4th Fighter Group website):

http://img2.photobucket.com/albums/v11/brentce/3e115824.jpg


<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by hotspace:
In late June of 1944, Spifire MkXIV's were modified to counter the V-1 threat. They gave it a higher boost rating and 150 Gas making it's Top Speed of over 400 mph on the Deck http://ubbxforums.ubi.com/infopop/emoticons/icon_smile.gif

Just as fast as the Hawker Tempest Mk V.

Hot Space

http://img11.photobucket.com/albums/v33/Hot_Space/me1.jpg <HR></BLOCKQUOTE>

Hristo_
02-05-2004, 12:48 PM
A smart 190 pilot will always have enough alt to dive away for a Spit. Since 190 is a superior diver, it will build up distance very quickly. And since it is faster on the deck, Spit will never have the chance to down it.

Some hot rodded clipped versions might be more dangerous, but in general Spit is never a problem for a 190 speedwise.

blabla0001
02-05-2004, 01:39 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Hristo_:
A smart 190 pilot will always have enough alt to dive away for a Spit. Since 190 is a superior diver, it will build up distance very quickly. And since it is faster on the deck, Spit will never have the chance to down it.

Some hot rodded clipped versions might be more dangerous, but in general Spit is never a problem for a 190 speedwise.<HR></BLOCKQUOTE>

Untill the Spitfire XIV and Tempest V will arrive, especially the Tempest V will match up pretty well against a FW190 and the Tempest V is much faster on the deck.

Hristo_
02-05-2004, 11:21 PM
Well, this is a thread about Spits, not Tempests, right ? http://ubbxforums.ubi.com/infopop/emoticons/icon_wink.gif

Now, if you use the most optimistic date of introduction of the XIV, then it would face Fw 190A-8. The latter is marginally slower on the deck, while still being a better diver. It might be rough for Fw jock over a prolonged chase. If you consider XiV's real opponent, the Dora, then it is no contest - Dora outdives the XIV and is faster down low.

As for Tempest, it has a performance degradation at 10 kft, so serious that it can be outrun by any contemporary LW fighter at that alt. After that it gets better, but Temp is really a low level fighter. Still it is a tough opponent and I would seriously consider flying a 262 if Tempest is around http://ubbxforums.ubi.com/infopop/emoticons/icon_wink.gif.

Some borrowed charts:
http://www.hitechcreations.com/ahhelp/models/charts/spit14speed.gif

http://www.hitechcreations.com/ahhelp/models/charts/tempestspeed.gif

http://www.hitechcreations.com/ahhelp/models/charts/190a8speed.gif

http://www.hitechcreations.com/ahhelp/models/charts/190d9speed.gif

and for kicks http://ubbxforums.ubi.com/infopop/emoticons/icon_wink.gif

http://www.hitechcreations.com/ahhelp/models/charts/me262speed.gif

HellToupee
02-05-2004, 11:29 PM
so the 190 dives down to the deck and tries to run home, the spitfire stays at alt, which would probly would have a top speed greater than the 190s deck speed, eventually the spit catches it after 190s inital speed from the dive and has an alt advantage http://ubbxforums.ubi.com/infopop/emoticons/icon_smile.gif, if 190 catches me on the deck ill just have to exercise my manoverabilty and climb advantage to drag the fight over 900meters.

http://lamppost.mine.nu/ahclan/files/sigs/spitwhiners1.jpg

Hristo_
02-05-2004, 11:51 PM
yea, might as well fly at 25000 ft and catch everyone eventually ! and with alt advantage, not to forget http://ubbxforums.ubi.com/infopop/emoticons/icon_wink.gif

somehow, it doesn't work that way http://ubbxforums.ubi.com/infopop/emoticons/icon_wink.gif

There is a technique for thisa, but it doesn't involve staying at alt. More with basic geometry, but I will keep my mouth shut, as I'm a 190 type myself.

DaBallz
02-06-2004, 03:03 PM
Dang, you guys don't look at the whole picture.
First, the guy who dives away probably has also ended
the engagment. Why?? because you are not going
to keep those planes at WEP, Emergency or WFO power settings
for a long time. The Fw-190 dives away, the Spit
stays high, and both overheat in the chase.
Both then break and run for home to avoid a long
walk or worse, a prison camp.

Those planes that can stay on the pin longer
do hold a certain advantage. A P-51D in good
running
condition would be a great choice for the long chase.
All the previously mentioned planes are close
in sea level speed, in the remote chance a long
chase occoured the guy who overheated first
most likely lost.
Probably the best non jet to be in is a P-51B, C, orD.
Great sustained speed. As fast or faster than
any of the previously mentioned planes at sea level.
But obviously a Me-262 wins, no contest.

Da...