[Bluebottle]

The problem with the 1C SpitIXs in speed terms is that they are all modeled on the F model - even the LF. If you note the heights at which the supercharger switches they are all the same, apart from the 25 and the HF. Even the VIII is the same. The supercharger profile looks like Oleg used Merlin 63 numbers. The LFs should be a Merlin 66, which would be faster low down, then worse up high, than the F. The 25 is definitely not the same engine model as the others, but unfortunately that extra performance coupled with the energy retention make the Spit 25 the contentious plane it is.

Once 150 octane fuel became available (in the RAF in Europe that was early 1945) all the Spit IX sqns over there were modified.

I hope one day someone will do some new slot IXs and LF IXs with a more realistic FM and the correct engine performance model

[Ltforce]

The problem with the 1C SpitIXs in speed terms is that they are all modeled on the F model - even the LF. If you note the heights at which the supercharger switches they are all the same, apart from the 25 and the HF. Even the VIII is the same. The supercharger profile looks like Oleg used Merlin 63 numbers. The LFs should be a Merlin 66, which would be faster low down, then worse up high, than the F. The 25 is definitely not the same engine model as the others, but unfortunately that extra performance coupled with the energy retention make the Spit 25 the contentious plane it is.

Once 150 octane fuel became available (in the RAF in Europe that was early 1945) all the Spit IX sqns over there were modified.

I hope one day someone will do some new slot IXs and LF IXs with a more realistic FM and the correct engine performance model

Blue bottle I agree with you 100% and I also noticed that the supercharger switches from M.S. to F.S. at the Merlin 63 height for all the spit IX models...hopefully they will fix it in the near future.

As for this 25LBS model it is bang on, I had just finished reading the tests performed by the RAE, in terms of climb and level performance and it was exactly as it was in real life in terms of climb and true airspeed at full throttle height!!!

Thank you very much and very well done Karaya!!

[lordish2001]

No but you can get 330 mph out of the IX spitfires in game at 200m alt, this is pretty much accurate for the IX. I regularly run tests for TAS on the Crimea map for my own survival knowledge and the Spitfire can do this.

How do you run tests for True Air Speed? I can't remember any plane in all of IL-2 that approaches listed speeds and altitudes by their airspeed indicators and it's driving me wacky.

Hilfe!

lordish

[Ltforce]

No but you can get 330 mph out of the IX spitfires in game at 200m alt, this is pretty much accurate for the IX. I regularly run tests for TAS on the Crimea map for my own survival knowledge and the Spitfire can do this.

How do you run tests for True Air Speed? I can't remember any plane in all of IL-2 that approaches listed speeds and altitudes by their airspeed indicators and it's driving me wacky.

Hilfe!

lordish

Push ctrl F1 while flying so you have no cockpit and take the airspeed there which is TAS and convert it to MPH.

[lordish2001]

How do you run tests for True Air Speed? I can't remember any plane in all of IL-2 that approaches listed speeds and altitudes by their airspeed indicators and it's driving me wacky.

Hilfe!

lordish

Push ctrl F1 while flying so you have no cockpit and take the airspeed there which is TAS and convert it to MPH.[/quote]

OK to avoid confusion (not easy with me)

You mean the figure in the HUD airspeed indicator? Not on the speedbar? THAT's the TAS?

lordish

[56RAF_Kernow]

The problem with the 1C SpitIXs in speed terms is that they are all modeled on the F model - even the LF.

Exactly. The ONLY 'LF' Mk.IX is the 25-lber, all the others are F-models whether they're labelled as F or LF (save for the clipped wing on the LFs, which, I believe, the 25-lber ought to have seeing it is an LF). The Mk.Vs are correct in that the LF versions do get better low alt peformance whilst sacrificing performance at altitude.

Probably too late to put a proper LF engine in the current LF Mk.IXs... I mean, most online dogfights happen at low level, so if Spit LF.IXs were any better down there they'd be too uber and need further community 'reworking'...

Push ctrl F1 while flying so you have no cockpit and take the airspeed there which is TAS and convert it to MPH

Strictly that gives you the groundspeed, but, provided there's no wind in the mission, that's the same as TAS.