F-15 Eagle: History, Performance & Discussion

Where does this come from?

Nvm found it. At M0.2 the F16C thats for an empty fuel F16 and its outside the cat 1 limiter. While the figure for the F15 is for 7500 lbs (55.5% internal), not clean. Clean it woukd be higher. AoA figures given by 23 sound good.



Tests done at 20kft by F15D

The info given by you and AoA info on the F-15 indicate it should have a higher lift coefficient than F16 so no need to pull lots of AoA imo. It can be closer to the max in the L/D curve.

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Are “units” in your source local or true AoA? It looks to be speaking to “true” AoA but says “units”… this is part of the confusion I was discussing.

I’ll read the document completely(tomorrow) to see if data comes from the ADC or just looking at instrument. I’m looking at the -1 and AoA instrument uses the 2 probes at each side of the front fuselage, measuring local AoA. Interestingly the ADC(air data computer) seems to convert that to True AoA for the lead computing gyro, central computer and True AoA is shown on hud when landing gear is down. AoA instrument shows local.

On flight characteristics section.

Departures should not be encountered below 30 units AOA at any altitude, airspeed or loading. The aircraft is resistant to departure at lower altitudes. Above 30 units AOA, external stores or asymmetry increases the departure susceptibility

The aircraft exhibits a slight reduced directional stability (yaw) in the 0.50 to 0.76 Mach and 40-44 units AOA region. In this region, departure resistance is decreased and spin susceptibility is increased. If controls are neutralized at the first indication of departure(large uncommanded roll or yaw), the aircraft will recover immediately. Even though the aircraft exhibits high directional stability, large lateral asymmetries can cause the aircraft to quickly enter a spin if not promptly recovered from a departure

A symmetrically loaded aircraft in this region will usually exhibit one or more classic signs of an impeding stall, such as wing rock(it may only be one) or yaw excursions.

I have seen 4 different formulas from degrees to AoA units on the F15. So dunno

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It’s an interesting discussion to be had before the F-15 gets here. Need to handle our expectations so when it’s not an AoA monster people aren’t surprised Pikachu face cuz it doesn’t match DCS

AoA(units) = AoA(°) + 10

Screenshot_20231028_215042
Screenshot_20231028_214856
Screenshot_20231028_214752

40-45 AoA units before departure

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Well, in level vertical pull-up scenario. When there is banking involved the forces of gravity and other conditions cause premature departure. In the F-15, it seems this is a bigger discrepancy than for aircraft like MiG-29… since MiG-29 can pull quite a lot of AoA in a turn whereas F-15 seems to suffer from lateral motions more.

No. If you look on the charts above. The wing rock excursions (70° bank) were in a less amount (±12°) than a 1g(level flight) stall(25°) and was pulling up to 40units.
And for 10° and 30°

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Is that not more than the MiG-29? MiG-29 can pull quite a lot more AoA than that, with stability during a bank iirc.

I have no serious knowledge on the mig 29 besides its radar so I can’t tell.
But there’a wing rock. Yaw starts to be in the 40 unit range at low speeds

I’d have to dig for a bit since I can’t read Russian but ultimately I think I have furthered my point and you’ve validated it well enough. The F-15 is not some AoA monster.

F-15 is not an AoA monster

Ofc not but 30°-35° is still quite a thing

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With a high level of buffet, wing rock, would not be able to really pull the nose to shoot someone like that. Quite a hail mary… and I don’t think it will come with AIM-9X so there will be little ability to do that while scissoring and little reason to do so when you have the high T/W and energy capacity… Just because you can doesn’t mean you should. On the same note, the MiG-23 can pull similar AoA just fine, doesn’t make it usable in the one circle against say a Kfir or M2K.

People make the F-15 out to be this one circle fighting king and superior to the Tomcat in that regard (due to DCS) when in reality, the Tomcat has better high alpha.

12° wing rock doesn’t sound too bad, had worse in the F4E. Just let the stick go like the manual states and voila. And you can see the trend for wing rock ° to decrease when bank angle increases per AoA unit. Thats a one time trick. But it has its merrit, high TWR will help it to just hang. I have never really depended on AoA in a fight. At high altitudes the high AoA helps

I don’t really think max AoA is the ultimate performance shit to die on. If you are pulling AoA you are a sitting duck eitherway.

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That’s another good point, I get stuck on a specific performance metric when discussing stuff sometimes. Good to look at the big picture of things.

The only thing I care for the F15 is fast acceleration, fly high, turn without bleeding half my speed, amazing radar and launch sparrows without RWR finding out

No cw illuminator
STT signal == signal sparrow homes in

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I think they’re gonna hand it AMRAAM to begin with to make it more than just variety.

I think they should add them before active missiles. Fox 2 era is better either way. No need for active missiles ingame and radars aren’t modled good enough nor aspect dependent RCS is a thong whicj should be a thing. Range doppler maps aren’t even used as you saw last discussion. Theres a reason you use FM in HPRF.

Just gonna bump this up with hopes and dreams we’ll see this baby soon XD

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I hope if the F-15 ends up coming this patch (not a believer till I see it) that gaijan finally models PDI, was hoping the F-16C wouldve been the one to do it (since afaik APG-68’s modded for sparrows lacked a CW illuminator and had a special high prf tracking mode for sparrows) but that ended up not being the case, but the F-15 is a more clear case with it lacking a CW illuminator

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F-15 will be excellent whenever its added, the APG-63 in its base form will be superb and the over all characteristics will resemble what the F-4E was several years ago. The best top tier all rounder.

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