FM's the State of Play with empasis on Climb performance.

[Kurfürst]

IMHO another thing that needs to be looked into is best climb speed. AFAIK the best speed for climb for the 109E in the sim is 270-280 kph IAS. This would be correct for the 109G, but the E's best climb rate was at 250 kph IAS.

This might sound as a small thing, but it seriously effect the climb curve. The FM calculates climb via a generic formula, where Vi=best climb is the peak and Vi= max level speed is 0. Shifting Vi=best climb to higher speed will thus reduce low speed (steep) climb performance and too low Vi= max level speed will reduce high speed climb, zoom etc.

This can and does effect tactics such as climbing turns, using different climb angles etc.

[IvanK]

My E4 Climb test flown at 250Kmh IAS 1.35/2350RPM (AUTO)

[Kurfürst]

A bit of a clarification, I wasn't suggesting you made your tests badly, dear Ivan! However from what I remember from the SFS files is that the best climb speed of the 109E in the sim is defined as 270 kph instead of 250.

[Crumpp]

My E4 Climb test flown at 250Kmh IAS 1.35/2350RPM (AUTO)

Did you write down the climb speeds you used as well?

AFAIK the best speed for climb for the 109E in the sim is 270-280 kph IAS. This would be correct for the 109G, but the E's best climb rate was at 250 kph IAS.

Kurfurst is correct. All aircraft performance occurs at a specific velocity and it fixed by the design.

If the relationships of lift and drag are correct in the model, it will reflect in the best rate of climb speed.

Those airspeeds are listed in the appropriate Operating Handbook for the type.

I would also suggest conducting saw tooth climb schedules to determine the Vy and Vx of the models in the game.

[IvanK]

The speeds used for these tests are those listed in the RAE test schedules so as to replicate the conditions in the test to those of the chart being used to plot the data. These speeds conform with those climb schedules in the relevant Pilots notes.

I am aware of best climb speeds Vx Vy etc and methods used to determine them.

[5./JG27.Farber]

the 250 IAS is for sea level, it drops over altitude.

For example the Bf109T

Alt - 0m's
Speed IAS - 250

Alt - 1000m's
Speed IAS - 243

Alt - 2000m's
Speed IAS - 236

Alt - 3000m's
Speed IAS - 229

Alt - 4000m's
Speed IAS - 222

Alt - 5000m's
Speed IAS - 215

Alt - 6000m's
Speed IAS - 208

Alt - 7000m's
Speed IAS - 200


So merely maintaining 250kmh for a 109 climb test is actually not its best climb. Just a thought.

[Crumpp]

the 250 IAS is for sea level, it drops over altitude.

Of course it does. This was another 100 page argument with folks on this forum. It changes with density altitude.

the Bf109T

Those are the same as the Bf-109E Flugzeug-Handbuch.

[Ernst]

The relative climb speeds, i.e., the difference between the climb speeds of all aircraft each other are in good agreement with RL.

Since to me there is no difference in the "fighting" aspect if the strategy used was to degrade RAF fighters or upgrade the LW ones.

Obviously I prefer that the LW ones upgraded to its RL curves. But if someone is complaining that they were being shot down because the RAF are uncompetitive in climb area I disagree.

[Robo.]

Originally Posted by Ernst

The relative climb speeds, i.e., the difference between the climb speeds of all aircraft each other are in good agreement with RL.

Well they are certainly not.

[Ernst]

And more there were some error due the fact there is no guarantee that the pilot used the maximun aircraft performance only because he is human. Was the tests repeated extensively do determine an average that the pilot can climb the aircarft? Yes or no? Due to this the relative (difference in) climbs are in good agreement. Second the quantity represented is not rate of climb.

From the error theory the error should be the minimun grade/2, i.e, sigma = 2.5ftm/2 = 1.25m = 1m15s. Considering this error the relative climbing can be considered in good agreement.