Acceleration comparisons

[SadoMarxist]

Originally Posted by majorfailure

Quote:
Originally Posted by gaunt1 View Post
Thank you again Horseback!



How can I check that? Is there an update/patch that adds acceleration graph? My version (4.11) has only summary, speed, rate of climb, ROC vs climb speed, turn time and fan plot.

I think initial acceleration is roughly proportional to max RoC.

Exactly. The climb vs TAS diagram for a certain altitude also represents the Ps diagram for that altitude. To get the exact value of acceleration an aero plane can have in level flight at a certain altitude and airspeed multiply Ps value for said altitude and airspeed by gravitational acceleration and divide it by airspeed. Comparison of the ability of two aircraft to accelerate in level flight takes only a look at the ROC vs airspeed diagram in IL- 2 compare with the two aircraft selected: that which can out climb can also out accelerate. To express that in percents for a certain airspeed just calculate the percentage of advantage in ROC one aero plane holds over the other. Off course, we only have these diagrams available for sea level, but MaxGunz already explained this.

[MaxGunz]

I thought we only have them for 1000m.

But for many speeds at whatever alt we can compare FW accel to other planes *at the same speed*.

For the math challenged who can use the Windoze calculator, if you take the speed of the faster plane and divide by the speed of the slower plane then subtract 1 and multiply the result by 100 you will get the percent that the faster plane is faster.

640 / 620 = 1.032258064516129032258064516129

subtract 1 to get .032258064516129032258064516129

times 100 is 3.2258064516129032258064516129

640 is 3.2% faster than 620.

Comparing acceleration is the same way only it's acceleration, not speed.

Now repeat after me: The Sky Is Falling! The Sky Is Falling! It's A Conspiracy! The Sky Is Falling!

[gaunt1]

According to that formula, La-5FN acceleration is 55.555...% better than La-5F. I think 15-20, maybe even 30% would be acceptable for a meager 150hp more powerful engine + a tiny little less drag (but 60-100kg higher weight). If you check NII VVS tests, you can see maximum 20-25% improvement in other performance charts, (speed, climb, turn time) nowhere near the 55%. Obviously prototype performance. If you still think this isnt suspicious...

[majorfailure]

Originally Posted by gaunt1

According to that formula, La-5FN acceleration is 55.555...% better than La-5F. I think 15-20, maybe even 30% would be acceptable for a meager 150hp more powerful engine + a tiny little less drag (but 60-100kg higher weight). If you check NII VVS tests, you can see maximum 20-25% improvement in other performance charts, (speed, climb, turn time) nowhere near the 55%. Obviously prototype performance. If you still think this isnt suspicious...

I really don't see where your 55% come from, from il2compare I get climb at sea level La-5F: 17.5 (21.5 with boost) and La-5FN 21.2 (25.3), which both is around 20% better acceleration for La-5FN

[SadoMarxist]

Originally Posted by majorfailure

I really don't see where your 55% come from, from il2compare I get climb at sea level La-5F: 17.5 (21.5 with boost) and La-5FN 21.2 (25.3), which both is around 20% better acceleration for La-5FN

Beat me to it

[MaxGunz]

Ps is for both altitude and speed.

There is no one ratio at any height that expresses La5 vs La5FN.
Even worse is trying to nail one number as the complete plane vs plane comparison.

I have IL2Compare 4.07m. I never bothered to upgrade since because why?

La5 at 0m alt ROC at TAS 280 kph is about 18 m/s and La5FN about 22.
La5 at 0m alt ROC at TAS 400 kph is about 12 m/s and La5FN about 16.
La5 at 0m alt ROC at TAS 500 kph is about 2 m/s and La5FN about 7.

La5FN to La5 Ps ratios?

At 280 kph, 122%. At 400 kph, 133%. At 500 kph, 350%.

FWIW, playing on performance margins is and has been part of aerial combat since fighter pilots noticed such margins in WWI.

And once you get over the charts (some never do) you might realize that what Pilot A can do in Plane X vs what Pilot B can do in Plane Y is -part- of the real difference with start conditions able to overturn that which is why aerial combat tactics always begins with initial positioning and speed.

IL2 has high realism. History tells of whining fighter pilots, at least in the USAAF where they wouldn't get shot for it.

[JtD]

Originally Posted by MaxGunz

At 280 kph, 122%. At 400 kph, 133%. At 500 kph, 350%.

Highlighted for importance.

[MaxGunz]

Originally Posted by JtD

Highlighted for importance.

La5FN to La5 Ps ratios?
At 280 kph, 122%. At 400 kph, 133%. At 500 kph, 350%.

Keep in mind that the last ratio is between La5 being near to zero climb at 2 m/s and La5FN at 7 m/s. The absolute differences all down the curves run La5FN as from 4/ms to 5 m/s more even though the ratios change so greatly.

Besides, the real shock is when the La5FN can still climb while the La5 has to fly a shallow dive to keep the same speed.

Compare a FW190A-3 to a contemporary Spit VB. Tactic for the 190 is to force the Spit to higher speeds. Tactic for the Spit is to force the FW to turn.

[SadoMarxist]

Originally Posted by MaxGunz

Ps is for both altitude and speed.

There is no one ratio at any height that expresses La5 vs La5FN.
Even worse is trying to nail one number as the complete plane vs plane comparison.

I have IL2Compare 4.07m. I never bothered to upgrade since because why?

La5 at 0m alt ROC at TAS 280 kph is about 18 m/s and La5FN about 22.
La5 at 0m alt ROC at TAS 400 kph is about 12 m/s and La5FN about 16.
La5 at 0m alt ROC at TAS 500 kph is about 2 m/s and La5FN about 7.

La5FN to La5 Ps ratios?

At 280 kph, 122%. At 400 kph, 133%. At 500 kph, 350%.

FWIW, playing on performance margins is and has been part of aerial combat since fighter pilots noticed such margins in WWI.

And once you get over the charts (some never do) you might realize that what Pilot A can do in Plane X vs what Pilot B can do in Plane Y is -part- of the real difference with start conditions able to overturn that which is why aerial combat tactics always begins with initial positioning and speed.

IL2 has high realism. History tells of whining fighter pilots, at least in the USAAF where they wouldn't get shot for it.

I guess I still prefer to have some idea where one fighter can outperform the other, but I guess that's why I'll never get over the charts. Off course, nothing beats experience .

[IceFire]

Originally Posted by SadoMarxist

I guess I still prefer to have some idea where one fighter can outperform the other, but I guess that's why I'll never get over the charts. Off course, nothing beats experience .

Having that knowledge gets you started I feel. It's good to know your opponents potential... but if that potential is exploited is another story altogether, isn't it?