No joke: 248mph Hurricane dh5-20, 230mph Spit... what on earth is going on??
 

Ok, Lolsav's post has brought me to some startling findings...I am positive I am seeing clearly but you guys should see this for yourselves. Forgive me if this has been posted but there is definitely not one post i've read this in.

I always thought the Spit 1 and dh5-20 were slower in outright speed than the constant speed propellers. At least on Repka the 2a seems to be slightly faster than the 1 in outright speed on the deck. Well it seems Lolsav is definitely right; that is in fact not the case up higher and there's also another surprise!

17,000 feet:

dh5-20: 248mph (course/low rpm)
rotol 100octane with tit pulled: 220mph (just before engine blows)

Spit 1: 265mph (course/low rpm)
Spit 1a 100oct with full emergency boost: 230mph (just before engine blows)
Spit 2a full emergency boost: 230mph

Please test for yourself folks, I am not seeing things here.

Well, no mate, in a word.

The two speed DeHavilland prop provided a greater top speed than the CSP.
The advantage the CSP gave was in rate of climb, which was deemed more important in a short range interceptor designed to stop high flying bombers.

In fact, from memory (I'll check and come back), the original wooden fixed pitch prop provided even more top speed than the 2-pitch DeHavilland, but there were lots of other factors involved such as all up weight which became progressively heavier. Interestingly though, the DeHavilland prop was the heaviest of the early props, and required a lot of ballast in the rear fuselage in order to maintain the centre of gravity. This was because it was a metal prop, whereas the fixed pitch and surprisingly the CSP props were wooden.

Interesting stuff if you like buying books and that! :D

I think you've missed the point dutch... I am talking about in game Spit 1 vs 2a and more to the point... the dh5-20 is faster than the Spit 2a.

Oh, sorry me old chum, I probably did (few beers you know:) )

Yep we all know there are top speed issues with all the models, but the difference between the top speed of the props should be there. The DH prop should be faster on the level than the CSPs. Whether the difference in values is correct is another issue.

I'd have to have a bash at the DH5-20 v IIa myself to see what you're driving at perhaps.

Oh god.....more testing...........great...........:D

Spitfire performance comparisons fixed pitch 2 blade v 2 speed v constant speed props:

http://i91.photobucket.com/albums/k3...-page-003a.jpg

http://i91.photobucket.com/albums/k3...e-page-002.jpg
NB: The wooden ROTOL CSP is almost the same as the type fitted to the Spitfire IIa (N3171 was part of a batch of Spitfire Is in the N3--- series fitted with Rotol CSP and UHF radios and used operationally Feb - May 1940 by 54 and 66 Sqns)

http://i91.photobucket.com/albums/k3...e-page-002.jpg

http://i91.photobucket.com/albums/k3...e-page-002.jpg

In general the speed differences between various prop types seem to be reasonably well modeled for CLOD.

Just did a quick test, 17000ft with boost and 50% rads
Spit 1 270mph
Spit 1a 240mph
Spit 1a 100oct 240mph (blown engine)
Spit 11a 225mph
Hurri DH5-20 255mph
Hurri mk1 100oct 220mph (blown engine)
Hurri Rotol 245mph
conclusion :- 2 speed prop is faster on both types, 100oct is fragile,

ta. did you look at the 1a? (the 87 octane version)
Oh, I see now that someone else has added the 1a to this thread.

So... the 100octane planes are slower and the Hurricane is faster than the Spitfire. I actually couldnt get 50 percent radiator on the 100 octanes as they blew before I got an accurate measurement.

Can I ask what is it they did do right in this 'simulation'?

Ffs...

Morning! Bit more 'compus mentus' here too!

Thanks for posting this Trademe, It's something I hadn't really noticed as being such a marked difference. Something is definately out of whack here by the looks of things, so thanks for posting the thread up.

Great thread with great input from everyone.

Agreed, seems every time I fly on ATAG I eek out a bit more performance out of the red planes thanks to the input on here, will try the Spit 1 later
Salute to all

I used the table in the game manual to convert to TAS, but of course figs were given for 16,000 and 18,000ft, so the conversions are very rough. I'd be happy to stand corrected if they look off.

DH5-20 320mph
Hurri 100oct - 292mph

Spit I - 338mph
Spit Ia - 296mph
Spit IIa - 296mph
Spt Ia100oct - 295mph
SpitIIa - 295mph

thanks for those conversions

Our server, 71st and ACG Combined, runs with temps off. Try them there.

Dont forget there is a difference between TAS and IAS...

During the Storm of War Campaigns: Battle of Britian we went through 3 patches of the game and you can see the reds switch aircraft each patch.. I thought this was quite interesting also.

Interesting. I get in the case of the Spit MKI DH 2 Pitch and Spit MKIA CSP a 20MPH IAS diff at FTH. With the DH 2 Pitch being 20MPH IAS faster with Coarse pitch +6lbs. Compared with real life this is a little bit out as they should be a lot closer than this. Converting to TAS results in my test to a 16MPH TAS differrential


TAS in figures below.
http://i40.photobucket.com/albums/e2.../cspv2ptch.jpg

I don't suppose posting the chart, with conversions, will be a problem in an IL2 forum:
Red = trademe900
Blue & red = ATAG_Dutch conversions
Brown & red = RAE figures from Price - The Spitfire Story 2010

http://i91.photobucket.com/albums/k3...-page-006a.jpg

Just did some more testing, 1000ft with boost, 50% rads and 2500 revs when appropriate
Spit 1 250mph
Spit 1a 265mph
Spit 1a 100oct 290mph
Spit 11a 280mph
Hurri DH5-20 262mph
Hurri mk1 100oct 274mph
Hurri Rotol 258mph
conclusion :- 100 octane give superior performance at low altitude

Thanks Momod. I've done a lot of testing recently, and quite honestly I'm glad other people have 'taken up the baton' as it were!

This is as it should be, the 100oct should only have improved performance up to a certain altitude, which I forget at the mo.

The whole issue though, brings the problem of altitude inaccuracies in the game back to the fore. The fact that none of the aircraft can achieve documented operational ceilings makes one wonder how the 'atmosphere' is modelled. So the performance we get at 17.000 may reflect RL performance at 25,000 or something like that. This is one of the reasons I've done most of my testing at low alt. I don't trust the 'atmosphere'.

That still doesn't explain the DH5-20 Hurri being so much faster than the IIa however, at any height! :grin:

Last month I flew the Hurricane DH5-20, This month I`ve been flying the Spit 100 octane but last night I tried the Spit 1 and it seemed very good climbing out and at 15000 plus but on one flight I tangled with a 109 at different altitudes and ended up low where the performance seemed poor compared to the spit 100 octane, This seems to be confirmed by the top speed tests I`ve done at the different altitudes, It almost feels like they have recreated the High fighter/Low fighter configuration of IL2 1946
~S~ 56RAF_Rumba

Yes, that is also what I discovered, Spit 1 can actually stand half a chance at high altitudes on ATAG. The spit 1 is no joke, can get to 20,000 feet in 10 minutes standing it on it's tail.

I also get your same figures at low altitude, but I couldn't get 290mph in the Spitfire 1a octane.

Game is whacked.

Conclusion: If you are on Repka or flying low on ATAG pick Spit 2a. If you are doing high altitude flying and climbing, pick Spit 1.

For testing I set up a mission in full mission builder, for 1000ft it was set up to spawn at 1500ft and 490kmh as soon as it spawned engage autopilot, wait till it settles down and gets up to max speed then disengage autopilot, still flying level adjust radiator and revs then shallow dive to 1000ft hold it level for 20 seconds while any speed from diving has bled away then press pause and take a reading of the speed.
~S~ 56RAF_Rumba

The 100 Octane improves performance up to c. 10,000 feet, after which the boost drops off rapidly. The constant-speed props (de H and Rotol) provided the best overall improvements in T/O and landing distances, climb rate and ceiling.

Huh? Have you been on the tinnies old bean? The DH wasn't a constant speed unit......:confused:

NZ was referring to Real Life, not CoD's interpretation, old chap!


http://spitfiresite.com/2010/06/batt...ropellers.html

Ah, thanks mate. Easy to get confused, what?! As with MkI, MKIa, etc. ;)

There is one thing you are missing. You need much longer than 20 seconds for an accurate measurement. Put the game on 2x or 4x speed (trimmed properly of course), hold the altitude and then you can get a very accurate reading. 20 seconds is not long enough, it will hold speed from a slight dive for longer than you think, throwing measurements off.

Anyway... our figures are the same.

Oh another thing worth noting is that all the aircraft (including 109 a little but by far most notably RAF planes) perform way better with CEM off, completely differently actually. Much closer to real life performance.

Perhaps with the game in it's current porked state ATAG can try turn off CEM to give the reds a bit of a chance? Just a thought.

Snapper mate, do you have anything to add at this point? :lol:

Trademe, we've been working on this stuff for a few weeks now, and I agree completely. ;)

Edit: but not necessarily with ATAG turning temps off. :D

It gets a little confusing! A2A's Wings of Power Spitfire 1a has the 2-speed prop (with a hand control that looks like a bicycle pump! LOL) and the undercarriage is hand pumped up & down. To top it off, A2A asserts that the RAF pilots figured out how to create a variable speed effect by carefully manipulating this bicycle pump control in the middle of its travel, which A2A have modelled in. It's not Constant Speed, though, so it has to be carefully monitored since the engine rpms will wander up or down with maneuvering.

A2A's 2a is very similar to CoD's 2a, except it uses (correctly) a cartridge starter.

A2A "pro's"

Much more detailed cockpit - every switch, lever works
Engine performance considerably more powerful (similar to CoD's über Sissyfire 2a ver 1.05)
Engines harder to overheat (but they will)
Merlin engines sound like.....Merlin engines! (Not CoD's "Diesel Merlins")
Very detailed systems are modelled, including Oxygen
Maintenance on engine highly detailed

A2A "cons"

Gun button doesn't work!
Damage modelling largely confined to engine wear & abuse
Pilot figure uglier than CoD's pilot figure -- how can THAT be possible?

Trademe, have a look at this thread, from post #149 on. ;)

http://forum.1cpublishing.eu/showthr...839#post455839

IMHO Trademe hit the same conclusion independently as us re CEM off. Then you, Dutch, refined it down further to simply just turning Engine Temperature Management off (but leaving CEM on) here:

http://forum.1cpublishing.eu/showpos...&postcount=162

Then began a lot of work over at ATAG, not without some heated debate, but everyone pitched in with a wide series of tests on both of our Servers. I note that some squad servers have arrived at similar conclusions of their own and are running with ETM off. Although LW fighters gain some performance as a result, the RAF fighters receive the greatest benefit by far. The top of the line fighters are, in engine performance, almost equal. The RAF fighters still experience neg g cutout, self-destruct above 420 mph IAS in a dive, but their top speed matches their LW counterparts at sea level. It is still possible to overheat in a RAF fighter, 109's can still boom & zoom, but if two opposing pilots of "equal ability" meet on a co-energy basis....it makes for a long and exciting encounter.

It should be noted, though, that the ATAG servers are all operating "Full Switch" as always, with Engine Temperature Effects turned on.

No problem I should have calcifided...collaguated...er...clarified that point. :cool:

Awesome, you guys are way ahead of me.

I would love to play with just temperature management off but CEM on. For now it would bring this game back to life!!! Would be good times for sure. I for one can live with temperature off for the time being if it brings all flight models into spec.

It would actually be fun to fly 109 again.

Ahhhh, the fifth horseman of the apocalypse!!
My sentiments exactly!

:lol:

Ok, signature amended here too. :D