Spit/109 sea level speed comparisons in 1.08 beta patch

[NZtyphoon]

Originally Posted by Crumpp

Grab a dictionary and look it up....

Also, go to the local airport and ask a mechanic about the number of airplanes that just have longitudinal trim controls. It is pretty common for a well designed control system. Most modern SE airplanes have fixed trim for everything but the elevator.

So what? As per ususl Crumpp conflates modern civilian practices for sports aircraft and says this should have been the same on high speed fighters during WW2 How many high speed WW2 fighters has Crumpp flown?

Originally Posted by Crumpp

Why do you think the trim on the Bf-109 is set to 400 kph IAS???
Having a fixed trim condition is a great way to set the combat speed for your airforce.

Utter balony, it's a great way to ensure that once in flight pilots do not have the ability to trim the aircraft to suit the circumstances - the 109E rudder became increasingly heavy, to the point where it was almost impossible to use - it's interesting that later "tall tailed" 109 variants had a trim tab to help overcome this problem. Setting the "combat speed" to a uniform and abitrary 248 mph? What's the point of that?

Any WW2 fighter that used trim controls rather than fixed trim was, by Crumpp's definition, badly designed and therefore inferior to uber Luftwaffe aircraft.

[Robo.]

Originally Posted by NZtyphoon

Utter balony, it's a great way to ensure that once in flight pilots do not have the ability to trim the aircraft to suit the circumstances - the 109E rudder became increasingly heavy, to the point where it was almost impossible to use - it's interesting that later "tall tailed" 109 variants had a trim tab to help overcome this problem. Setting the "combat speed" to a uniform and abitrary 248 mph? What's the point of that?

Any WW2 fighter that used trim controls rather than fixed trim was, by Crumpp's definition, badly designed and therefore inferior to uber Luftwaffe aircraft.

It's not a question of which airforce had 'better' trim system.

It was just a different approach in USAAF and LW. LW fighters had no variable rudder trim and a/c was trimmed for certain cruise speed, so at most typical cruise speed pilot would not have to kick the rudder to compensate for sideslip. Allied fighter pilot would twist the rudder trim and climb or fly with feet off. No biggie imho, just more comfortable.

What Crumpp is saying that Emil was trimmed for 400kph because that was best combat speed. That is obviously wrong, 400kph was typical cruise speed (achieved at some 1.15ata and 2200 U/min). This worked in game btw, but then the devs changed the fixed trim value for 300kph for some reason, which is too low and now LW pilots complain because the Emil is very unstable during combat phase:

See bugtracker issue No. 387: http://www.il2bugtracker.com/issues/387

There is nothing wrong with 109E turning well at 400kph, it's actually pretty obvious to any virtual pilot in here, e.g. fast Emil will outturn slow Spitfire with no problem for long enough to score some hits. But as for sustained turn advantage in typical horizontal turnfight and as for 400kph turn used in TnB combat for long enough to be called sustained turn, that's all nonsense. 109 will win if the pilot keeps the speed up, but not via sustained turn performance advantage. At co-E situation, Spitfire would outturn and hit a 109 turning at 400kph flat with no problem. Just for long enough to score hits.

I'd say Crumpp is not entirely wrong here but his statements are irellevant to what is actually important in TnB combat (re: sustained turn argument). I don't blame him for he has no experience with combat sims.

He's wrong in his statement that 109E was trimmed for 400kph purely for combat purposes. Fixed trims are usually set for cruise speed even for fighter aircraft.

[Crumpp]

That is obviously wrong

Do the math....

[JtD]

The 12lb boost calculation done by the RAE is an absolutely reasonable extrapolation.

[Kurfürst]

Originally Posted by JtD

The 12lb boost calculation done by the RAE is an absolutely reasonable extrapolation.

I have my doubts about it having been made by RAE. It's an obvious farce.

[Crumpp]

The 12lb boost calculation done by the RAE is an absolutely reasonable extrapolation.

Well, then walk us through the explaination of how the engine data aligns with the graph. I would love to hear it.

Performance graph showing FTH of 11,000 ft:

http://www.spitfireperformance.com/s...-rae-12lbs.jpg

Engine data with RAM effect at max level speed showing FTH of 8,500 feet:

http://www.spitfireperformance.com/merlin3curve.jpg

[41Sqn_Banks]

Originally Posted by Crumpp

Well, then walk us through the explaination of how the engine data aligns with the graph. I would love to hear it.

Performance graph showing FTH of 11,000 ft:

http://www.spitfireperformance.com/s...-rae-12lbs.jpg

Engine data with RAM effect at max level speed showing FTH of 8,500 feet:

http://www.spitfireperformance.com/merlin3curve.jpg

Let's have a look at +6.25 boost ...

FTH at 17,000 ft (http://www.spitfireperformance.com/merlin3curve.jpg)
Max level speed at 19,000 ft (http://www.spitfireperformance.com/s...-rae-12lbs.jpg)

Looks like max level speed is achieved 2,000 feet above the FTH. Pretty much in line with the difference for +12 boost.

Edit: I want to make clear that this 2,000 ft difference between FTH and max speed must not be present in reality, it's more a systematical difference between the two charts that must be considered when they are compared.

[JtD]

Originally Posted by Crumpp

Engine data with RAM effect at max level speed showing FTH of 8,500 feet:

It's not with ram effect. That's painfully obvious from all the engine and plane data on 6.25lbs around. The power level generated by the engine on this chart has the designation "all out level" and that's all there is to it. Assuming otherwise is like assuming "combat" power is only available when the aircraft is in actual combat.

[JtD]

Originally Posted by Kurfürst

I have my doubts about it having been made by RAE. It's an obvious farce.

I agree it looks simplistic, but technically it is sound and I see no reason it not being an original document. No reason for it being one either, but I will accept it on face value as I see no reason to mistrust Mr.Williams on this issue. If you have more than a gut feeling, I'm willing to re-evaluate my opinion.