F-15 Eagle: History, Performance & Discussion

Does appear to instantly transfer the HPRF lock to MPRF which is why there is a brief Memory track.

No.

The F15 IRL automatically transfers to MPRF from HPRF at around 30 Nautical Miles, which is done ingame and the only part which he read from the manual. IF the sparrow isn’t selected. It doesn’t go to MEM as you can see, straight from HPRF to MPRF at 35 NM.
What happens with HPRF track is that the lock has never been stable as you can see, it never gives an accurate vector as its just shaking around and only stops once it goes to MPRF

Didn’t notice it, I think you are right.

Spoiler

Shameless plug
Shameless plug 2

So guys, how’s the aim120 after the nerf? I heard a Lot of ppl complaining but i didn’t have time to test it myself.

Still top 3 missile. By far the worst maneuvering Fox 3 but its still the longest range although not by much now.

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This could be tested

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I will run it later unless someone beats me to it.

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These aswell would be nice to have but I dont have these shots

Could just ask @Flame2512 to run them again

Try it again. The v1 got changed in 2.37.0.79, so maybe it was a fix for this.

US usually gets worse maneuvering missiles, or just worse missiles kinematically, the only advantage is IRCCM which more and more countries are getting with their missiles.

I would not say that is the case… can’t really think of any time that truly applies.
IRL the thing the US lacked was IRCCM whereas the maneuverability was quite good for the time they were employed.

9M was deployed in early 80s, along with R-60M and R-73 for example
Thats not really lack, when 9L had chances to hit AB target that uses flares.
Just on time

early models of the 9M had quite iffy IRCCM which later models would resolve

But that still irccm, yes, worser than later models of 9M

Considerably worse than the IRCCM of the Magic 2 or the R-73 by quite a large margin at the time.

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Does anyone know what Load factor is used in this chart? Is it the normal load factor N_z like in the F-16 manual or the load factor n_z ?

(N_z is the forces perpendicular to the aircraft body divided by the aircraft weight, aka it is:
N_z = \dfrac{(Lift * cos(AoA) + drag * sin(AoA)}{Weight}

while n_z is perpendicular to the airflow: n_z = \dfrac{(Lift * + thrust * sin(AoA)}{Weight} ).

I’ve noticed at mach 0.3 sea level that both the F-16 and the F-15A are doing around 17 degrees per second, but the F-16 has an indicated load factor of less than 3 while the F-15 one is above 3.

Turn rate as a function of load factor n_z is: ω = \dfrac{g \sqrt{n_z^2-1} }{V} \dfrac{180}{π} , and in a sustained turn (right now not bothered to write how it is derived) in a sustained turn n_z = \dfrac{N_z}{cos(AoA)} .

If we take 2.9G as a value for N_z for the F-16, get n_z considering that AoA is ~23 degrees and we use the formula above (mach 0.3 at sea level is around 99m/s), we get exactly ~17deg/sec, which is the value of the manual.

Doing the same thing for the F-15A (AoA is close to 22 degrees) with the ~3.15G value we obviously get much more than 17 deg/sec, around 18deg/sec.
If instead we use 3.15G directly as n_z we get 17deg/sec.

So either the turn rate chart is wrong (discrepancy is too high for it to be just mach to m/s speed conversion due to air temperature/pressure) or the overload in the chart is n_z instead of N_z, which means that the aircraft is modelled wrong in game.

At higher speeds the F-15A seems to over perform in STR even if we consider the values in the chart as N_z (N_y in localhost because Russians use weird convention even for the axis of the frame of reference) .

F-15C instead seems to lack speed at high altitude, although @MaMoran20 already reported this and gaijin decided to be gaijin.
@MaMoran20 is there a thrust curve for the engine in that appendix for the manual? Because while they might not do adjustments for just speed at high altitude, they may adjust the thrust (at least they did so for other aircraft).

(before someone asks no, not going to bug report the sustained turn rate right now, when I’ll do (if I’ll do) it will be with other aircraft at the same time since at least half of planes above 11.0 seem to over perform right now, fm quality seems to have lowered considerably in recent years).

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FM are such a mess.

Appreciate your concern and dedication ;)

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I’m not a math expert by any means, just a few observations.
In the chart for the F-15A you see an engine trim of 97.7%. That means the engine is underpowered. This was used for peacetime because engine reliability was worse and thus expensive to operate. You need a chart for 102% trim, which is 100% of the F-100 engine thrust.
Maybe this picture will help you a little, but it’s for the F-15C…
figure 5

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102% is already modeled in the game, though the chart you provided is for 97% trim as well.
The F-15’s IRL would NEVER operate at 102% trim in war time anyway, no plane would. Turbines used in fighter jets generally are not at 100% healthy thrust output due to wear and tear. Some fighters of the past operated at thrust percentages as low as 70%.

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