Author Topic: I remember some old posts discussing the AH's Spitfire IX as a Spitfire F.IX (Read 2442 times)

bunch · « **Reply #15 on:** January 12, 2005, 01:03:33 AM »

According to Jeffrey Quill's book, the outboard gun heating on the C wing was insufficient for the 20mm & it jammed in the cold. This is probably why the Mk.Vc Spits sent to Malta were armed 4 x 20mm, but ETO ones were not. I assume this issue was taken care of in the E wing, as the port for the 12mm gun looks like it was make for a 20mm, however I've never read anything by anyone who said they flew a 4 x 20mm Mk.IX into combat. The only 4 x 20mm Spits I've ever read about in WW2 combat were the Mk.Vc ones on Malta & although they were equipt with the massive battery I am not sure they were ever used in combat with the full arms package. I did read a book by one Malta RAF pilot (may have been Beurling) who said some prefer the weight saved by having only 1 cannon in each wing.

Staga · « **Reply #16 on:** January 12, 2005, 02:42:29 AM »

Notice that early Spit MkIXs still had float type carbs with neg-G cutouts.

Angus · « **Reply #17 on:** January 12, 2005, 06:45:55 AM »

Umm, this:
"According to Jeffrey Quill's book, the outboard gun heating on the C wing was insufficient for the 20mm & it jammed in the cold. This is probably why the Mk.Vc Spits sent to Malta were armed 4 x 20mm, but ETO ones were not"

Is it from "Spitfire: A test pilots story"?
Anyway, I may have misunderstood this some time ago, but anyway, I thougt the problem was overheating.
At medium to high alt, the air in the med is actually colder than in Britain/France!!!!

Guppy35 · « **Reply #18 on:** January 12, 2005, 07:37:48 AM »

Quote

Originally posted by Angus
Umm, this:
"According to Jeffrey Quill's book, the outboard gun heating on the C wing was insufficient for the 20mm & it jammed in the cold. This is probably why the Mk.Vc Spits sent to Malta were armed 4 x 20mm, but ETO ones were not"

Is it from "Spitfire: A test pilots story"?
Anyway, I may have misunderstood this some time ago, but anyway, I thougt the problem was overheating.
At medium to high alt, the air in the med is actually colder than in Britain/France!!!!

Yep, it's in Test Pilot's Story.

As for 4 cannon Spits. The only evidence I can find of any kind of squadron use was with 2 Squadron SAAF in the ground attack role in Italy in 44-45.

The Malta Spit Vcs in 42 were launched from Wasp with 4 cannons but they removed two after they arrived.

Image of 2 Squadron Spit Vcs with 4 cannon. Note they also had that large Vokes filter under the nose and carried 500 pound bombs. Not exactly a high performance Spit under those circumstances

Dan/Slack

Guppy35 · « **Reply #19 on:** January 12, 2005, 07:40:35 AM »

Quote

Originally posted by Staga
Notice that early Spit MkIXs still had float type carbs with neg-G cutouts.

Interestingly the first Griffon Spit XIIs that arrived at 41 Squadron in February 43 still had those carbs too and suffered the engine cut out problems initially.

They fixed it quick, but considering they'd changed it on the Spit Vs, it's surprising they still were dealing with it in 43.

Dan/Slack

Angus · « **Reply #20 on:** January 12, 2005, 07:43:39 AM »

Saw a picture of a 6 cannon Spit somewhere.
Anyway, was this a heating or cooling problem?

MiloMorai · « **Reply #21 on:** January 12, 2005, 08:09:32 AM »

Angus, here is a nice pic for you. Lots of Spits in it.

The 6 cannon Spit was only a mockup. Dan will know for sure.

Guppy35 · « **Reply #22 on:** January 12, 2005, 08:10:25 AM »

Quote

Originally posted by Angus
Saw a picture of a 6 cannon Spit somewhere.
Anyway, was this a heating or cooling problem?

The 6 cannon Spit was the prototype Spit XII DP845 that for a brief time in May 42 had a wooden mock up of a 6 cannon installation. It never had the real deal.

It was a heating issue with the 4 cannon Spits. I guess that explains the only use being in the Med at low level where heating wasn't an issue.

Image is DP845 with the 6 cannon mock up

Dan/Slack

Karnak · « **Reply #23 on:** January 12, 2005, 10:13:20 AM »

Wotan,

The Spitfire LF.Mk IX is 15mph faster on the deck, using +18lbs boost, than the Spitfire F.Mk IX and it has about an 800fpm better climbrate. Those are both significantly better numbers.

Personally, I don't like the clipped wings, but I recognize that if we get a LF.IX it will have them. They's ugly and ruin the Spitfire's lines, IMO.

I agree about the Mk V. Frankly I can't understand why it was boosted to +16lbs in AH2. It creates a large gap. Perhaps they should rename it "Spitfire Mk Vc" and add in a "Spitfire MkVb" at +12lbs boost with a float carburator and 60 rounds per cannon.

Flyboy · « **Reply #24 on:** January 12, 2005, 12:52:46 PM »

whats the difference (in performence) between the spit F.IXs that has the merlin 61 to the spit F.IX that is powered by a merlin63 and a merlin 63a?

and why did they named them all F.IX?

Guppy35 · « **Reply #25 on:** January 12, 2005, 01:07:00 PM »

The LF, F, HF designation referred to the altitiude band the engine was best suited for.

HF and the Merlin 70 obviously being optimized for very high alt work.

F for high to medium alts

LF for medium to low alts

Dan/Slack

Wotan · « **Reply #26 on:** January 12, 2005, 03:01:23 PM »

Quote

Wotan,

The Spitfire LF.Mk IX is 15mph faster on the deck, using +18lbs boost, than the Spitfire F.Mk IX and it has about an 800fpm better climbrate. Those are both significantly better numbers.

I know, I just don't think its something to be feared or 'unwanted' in AH. I consider the above numbers as at best a moderate gain.

When I mentioned speed comparisons I was talking mostly about the LF.IX vrs the LF.IX clipped wing. The only real advantage I see worth mentioning is the improved roll rate, especially at lower speeds.

IMHO things like roll rate and turning are overated in these games. Its my opinion that acceleration and climb rate are far more important, at least in how I fly.

Basically I don't see any practical advantage in a clipped wing Spit over a standard winged Spit.

The LF.IX will certainly have a speed advantage over the F.IX at normal combat altitudes in the main but from what I read the clipped wing spits climbed slightly worse then their normal wing cousins.

Guppy says (referring to the clipped wing):

Quote

the turn rate and climb were not greatly affected.

I will take his word for it but I would prefer the better climbing variant, even if its only slightly better, any day.

Clipped wing aside, I think most of us agree a Spitfire LF.IX is a plane that AH could use.

The F.IX should be fixed to represent its true design.

Rename the Spit Vb a Spit Vc and add a new Spit Vb with a max 12lbs boost.

It seems to me these would be relatively minor model changes. just new engine modeling work and FM adjustments.

If they are going to re-work the models anyway then why not?

I am still waiting to see a Yak 9m (basically a 9t with a 20mm ShVak).

Anyway we will see...

bunch · « **Reply #27 on:** January 13, 2005, 02:27:28 AM »

Quote

Originally posted by Angus
....At medium to high alt, the air in the med is actually colder than in Britain/France!!!!

Really? I never knew the lapse rate varies with lattitude. What is the function for lapse rate vs. lattitude?

Angus · « **Reply #28 on:** January 13, 2005, 06:14:05 AM »

Don't really know, just had it from a pilot who fought in the med, and later flew all over the globe.
He just said he was surprized to find out how quickly it got cold there, and that it was actually colder than in N Europe.

Kev367th · « **Reply #29 on:** January 13, 2005, 06:32:59 AM »

Of course an easy quick fix would be to unperk the 14, it's not worth the perks anyway.
It only excels at hi-alt and most of the time if you come across a con they dive for the deck.
Still can't see how HT can justify the cost of a Spit 14 when Ponys, Lala's and 190D9's are free. Just plain insanity.

What are the criteria for perking -
1) If its to prevent overuse then the Pony, Lala and 190d9 definately fall into this category.
2) If its #s built then there are still unperked aircraft built in lower numbers than the Spit 14. La7 3 cannon option is one.
3) Or is it as I suspect just at HT's whim.

Any other ideas or explantions welcome, just to try and help me understand this clusterflob called perking.