Speed graphs for Spitfire and Hurricane

[ATAG_Snapper]

Originally Posted by BlackSix

We don't have official flight tests for Spits and Hurris between 0 and 3000m.

Thanks, Black Six. At last we finally know why the Spitfire Ia's top speed at sea level is 240 mph. The slope of the curve was simply applied to the 0 - 3000 m gap in information, so 0 feet = 240 mph. Mystery solved.

[41Sqn_Banks]

Originally Posted by ATAG_Snapper

Thanks, Black Six. At last we finally know why the Spitfire Ia's top speed at sea level is 240 mph. The slope of the curve was simply applied to the 0 - 3000 m gap in information, so 0 feet = 240 mph. Mystery solved.

This chart gives speed down to 0 feet. I think it's calculated as the test log only goes down to 3000 m.

[ATAG_Snapper]

Thanks, Banks. That chart squares very closely to what we all KNOW how a Spitfire Ia performs at sea level. The vast majority of dogfights on the ATAG Server occur well below 3000 meters, including those that start above that mark inevitably descend well below it.

For a year the CoD RAF fighters (save the IIa) have been saddled with poor low altitude performance, with the only fighter, the Spitfire IIa the only one which comes close to historical performance at low altitude (300 mph at sea level vs 290 mph historically). Yet in the face of stiff opposition by many of those who fly 109's, the IIa was either excluded or severely limited in the ATAG plane sets. Now we've been advised that the IIa will be nerfed in the upcoming patch by as much as 60 mph at some point(s) on the speed curve. In view of the Rotol and Ia information, confidence by many who choose to fly RAF fighters is very low that correct flight modelling for all three models (Ia, IIa, Hurricane Rotol/Ia) will actually be done in this upcoming patch.

All many of want is an ACCURATE representation of ALL fighter flight models for BOTH sides. The Spitfire Ia was considered a serious threat by Luftwaffe 109 pilots during the Battle of Britain at ALL altitudes. In Cliffs of Dover, the "Sissyfire" Ia is a cruel joke that has lasted over a year -- anyone who plays Cliffs of Dover doesn't need performance charts to realize that. Why can't the devs see that?????

[BlackSix]

Originally Posted by ATAG_Snapper

Thanks, Black Six. At last we finally know why the Spitfire Ia's top speed at sea level is 240 mph. The slope of the curve was simply applied to the 0 - 3000 m gap in information, so 0 feet = 240 mph. Mystery solved.

More correctly: we didn't have official flight tests for Spits and Hurris between 0 and 3000m for this test.
I don't know how our FM programmer made this planes for game in 2011.

[ATAG_Snapper]

Originally Posted by BlackSix

More correctly: we didn't have official flight tests for Spits and Hurris between 0 and 3000m for this test.
I don't know how our FM programmer made this planes for game in 2011.

Thanks, Black Six. I think we've got it figured out.

[klem]

Originally Posted by BlackSix

More correctly: we didn't have official flight tests for Spits and Hurris between 0 and 3000m for this test.
I don't know how our FM programmer made this planes for game in 2011.

BlackSix

This page gives sea level to 29,000 feet figures for the Spitfire with Merlin III @ 6.25lbs boost:
http://www.spitfireperformance.com/spit1vrs109e.html
and this gives it for the Hurricane:
http://www.wwiiaircraftperformance.o...rricane-I.html

I've placed your Patch Data on top of these and projected the sea level speeds (see attached) and both are looking too slow from sea level to 20k and 16k respectively. At sea level the Spitfire is looking to be 255mph instead of 283mph (28mph slow) and the Hurricane 240mph instead of 262mph (22mph slow).

Can you please confirm that the patch FM is still being adjusted to RL data (or that it will be)?

[41Sqn_Banks]

Originally Posted by klem

BlackSix

This page gives sea level to 29,000 feet figures for the Spitfire with Merlin III @ 6.25lbs boost:
http://www.spitfireperformance.com/spit1vrs109e.html
and this gives it for the Hurricane:
http://www.wwiiaircraftperformance.o...rricane-I.html

I've placed your Patch Data on top of these and projected the sea level speeds (see attached) and both are looking too slow from sea level to 20k and 16k respectively. At sea level the Spitfire is looking to be 255mph instead of 283mph (28mph slow) and the Hurricane 240mph instead of 262mph (22mph slow).

Can you please confirm that the patch FM is still being adjusted to RL data (or that it will be)?

Thank you klem. This is so far the best post in this thread.

[Osprey]

A useful post Banks but again referring to 6.25lbs boost (87 octane) in the rhetoric. As you know, 12lbs was available according to operating limits on the engine, this puts the Spitfire faster on the deck than the 109, not the 50kmph slower we are seeing here. That said, these graphs do plot the 12lbs boost speeds and it is these that require modelling, once cleared by the likes of those who 1C has an ear for.

[Flanker35M]

S!

So the +12lbs boosted performance made Spitfire faster on the deck. What was the speed without the boost then? 5 minutes maximum is not a long time nor is the 1min or so for Bf109E.

[Kwiatek]

Originally Posted by Flanker35M

S!

So the +12lbs boosted performance made Spitfire faster on the deck. What was the speed without the boost then? 5 minutes maximum is not a long time nor is the 1min or so for Bf109E.

Flanker 1.4 Ata is 1 minut short emergency power and 1.3 Ata for 109 E is also only 5 minut emergency power. Nominal ( continous 30-minut) power is 1.23 Ata for DB601.

For Spitfire MK I maximum speed at nominal power - 6 1/2 lbs is 283-288 mph/455-463 kph ( everything is on charts poseted in these topic)

" The A.&A.E.E. trials of N.3171 resulted in level speeds of 283 mph at sea level and 354 mph at 18,900 feet with the Merlin engine operating at 6.25 lbs/sq.in., 3000 rpm. 1d For comparison, Spitfire Mk. I R.6774 equipped with de Haviland Constant Speed Airscrew and armoured windscreen achieved 288 mph at sea level and 355 mph at 17,800 using 6.25 lbs/sq.in., 3000 rpm. The similarly equipped Spitfire I R.6770, except fitted with 2 cannons and four Browning guns, reached 358 mph at 18,000 ft. The Royal Aircraft Establishment (RAE) obtained 314 mph at sea level and 359 mph at a full throttle height of 11,500 feet using +12 lbs/sq.in. boost"