Spit/109 sea level speed comparisons in 1.08 beta patch

[Crumpp]

Without this calculation the charts you posted are of little value

Problem is we don't have any good data on the 100 Octane.

The only data we have does not match our engine curves. Find some good data and I will be happy to do the calculations.

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

Takes but a second to change the values.

[Crumpp]

It just does not do it under all conditions or speeds. That is important, Glider.

That is how airplanes work, Glider.

It is not going to outperform the Bf-109 without changing the physics. The Spitfire has to be faster and have more excess thrust.

It is going to be very tough for the heavier Spitfire to overcome the weight differences when the Bf-109 maintains power parity.

It is that simple.

[NZtyphoon]

Originally Posted by Crumpp

Why do you think the trim on the Bf-109 is set to 400 kph IAS???

You do understand they can trim the aircraft for whatever speed they desired?? Having a fixed trim condition is a great way to set the combat speed for your airforce.

This is priceless - doesn't Crumpp know that apart from the variable incidence tailplane of the 109 the trim for all control surfaces had to be set on the ground, whereas the Spitfire could be trimmed in flight by the pilot using tabs on the elevators and rudder? For example, the speeds for aerobatics posted in the Spitfire II PNs:



The optimum trim for a 109 was set for 400 kph (248 mph)? No wonder the controls got so heavy at higher speeds.

[Glider]

Originally Posted by Crumpp

Problem is we don't have any good data on the 100 Octane.

The only data we have does not match our engine curves. Find some good data and I will be happy to do the calculations.

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

Takes but a second to change the values.

What exactly would be your definition of good data?

[Christop55her]

I don't care if the failure rate is 100% at 6 minutes it's just highly unrealistic to have guaranteed failure at 5:01.

[Crumpp]

What exactly would be your definition of good data?

Data that matches the characteristics of the engine and makes sense.

If our engine has a RAM FTH of say 12,000 feet and our data shows a FTH of 8,000 feet....

It is not the same engine in the airplane. If we use the power data from the wrong engine with the wrong speed....our result's will be just as incorrect!

[Crumpp]

NzTiffoon says:
109 the trim for all control surfaces had to be set on the ground

Crumpp says:
fixed trim

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.

[Al Schlageter]

Originally Posted by Crumpp

It is pretty common for a well designed control system. Most modern SE airplanes have fixed trim for everything but the elevator.

So you are saying that the Americans did a bad job in designing the control system of their fighters as the had to put trim on the elevator, rudder and ailerons?

How many modern s/e a/c have a speed range of a WW2 fighter?
How many modern s/e a/c have a disposable load that a WW2 fighter has?
How many modern s/e a/c swing a 10' plus prop turned by 1500hp plus engine?

[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.