Aces High Bulletin Board

General Forums => Aircraft and Vehicles => Topic started by: Karnak on March 17, 2002, 09:49:41 PM

Title: Spitfire Mk Ia and Bf109E-4 climb rates
Post by: Karnak on March 17, 2002, 09:49:41 PM

It looks like, from the climb charts in AH, that the Spitfire Mk Ia and Bf109E-4 have nearly identical climb performance for the first 8,000ft, after which the Bf109E-4 pulls away.

(http://www.hitechcreations.com/models/charts/spit1climb.gif)
(http://www.hitechcreations.com/models/charts/109e4climb.gif)

The information I am familiar with has always indicated that the Bf109E-4 climbed significantly better than the Spitfire Mk Ia.

Initial climb rate of 3,280ft per minute, and 7 minutes and 45 seconds to 19,685ft for the Bf109E-4.

Climb rate of 2,530ft per minute and 9 minutes 24 seconds to 20,000ft for the Spitfire Mk Ia.

If this is correct, it seems that the Spitfire Mk Ia climbs too fast in AH.

Title: Re: Spitfire Mk Ia and Bf109E-4 climb rates
Post by: SageFIN on March 18, 2002, 06:38:00 AM

Quote

Originally posted by Karnak
Climb rate of 2,530ft per minute and 9 minutes 24 seconds to 20,000ft for the Spitfire Mk Ia.

In the other thread you just started, you spoke about different engines on same models. I would presume that the Spit Ia was produced with perhaps at least two different Merlins. If so, then what engine does that figure correspond to? If that's the best figure there is, then ok, there might be an error but if not, then maybe the apparently too high climb rate could be explained with a better engine.

Title: Spitfire Mk Ia and Bf109E-4 climb rates
Post by: juzz on March 18, 2002, 07:11:06 PM

9:24 to reach 20k is correct for a Spitfire I (Merlin I engine using 80 octane fuel and about +6lbs boost) with a 2 blade fixed pitch wooden propellor.

For a Spitfire I (Merlin III using 100 octane fuel and +9lbs boost) fitted with a 3 blade CS prop, it took about 7.7 minutes to reach 20k.

Title: Spitfire Mk Ia and Bf109E-4 climb rates
Post by: Karnak on March 18, 2002, 08:41:03 PM

My numbers were for a Merlin 3 with a 3 blade prop.

Title: Spitfire Mk Ia and Bf109E-4 climb rates
Post by: Tac on March 18, 2002, 08:56:54 PM

SAge, where you get your sig from?

I have a poem called "The Blood of Ages" by Trent Nevermore, those lines arent in it (or I have it incomplete?)

Can you give me a URL pleasE?

Title: Spitfire Mk Ia and Bf109E-4 climb rates
Post by: Nashwan on March 19, 2002, 06:36:09 AM

Juzz, are you sure the Spit took 7.7 mins at 9lb boost?

The test of Spit II P7280 (online at http://www.fourthfightergroup.com/eagles/spit2.html

compares it's performance to Spit I  N3171. They give a time to 20,000ft of 7.7 mins, and say the plane was running at 6.25lbs boost, compared to 9lbs for the Spit II under test.

I'd say the AH figures for the web chart look about right for a Spit Ia on 100 octane fuel.

Title: Spitfire Mk Ia and Bf109E-4 climb rates
Post by: SageFIN on March 19, 2002, 06:45:26 AM

Quote

Originally posted by Tac
SAge, where you get your sig from?

I have a poem called "The Blood of Ages" by Trent Nevermore, those lines arent in it (or I have it incomplete?)

Can you give me a URL pleasE?

The sig is not poetry but excerpt of a song by the same name. The lyrics are written by Josh Pincus of Ice Age, a prog rock band from NY, USA. So probably you have the poem in its entirety. The URL for Ice Age's website. (http://www.ice-age.com)


Also, why the discrepancy between Karnak's and juzz's numbers? Karnak, were your numbers also for 100 octane fuel and +9 lbs boost and was using those the norm for Merlin III Spitfires?