01 Dec 2016, 17:53

I have those charts up right now. First of all, looking at the chart it take 68s to accelerate from 0.8-1.2M, not 90s.

F-15C with (4) AIM-7, (4) AIM-9, CL pylon, PW-220 engines, and at 48,000lb (~14% lighter than the Eagle sheet on the previous page) 40K 0.82-1.22 acceleration is 77s. Weight corrected to 42,000lb gives 67.4s. (Gives performance advantage relative to PW-200 engines on previous page)

F-15C clean, PW-220 engines, and at 40,000lb (~5% lighter than the Eagle sheet on the previous page) 40K 0.82-1.22 acceleration is 50s. Weight corrected to 42,000lb gives 52.5s. (Shows how much drag is caused by the air-to-air load)

F-15E with no CFT, PW-220 engines, and at 42,800lb (~2% heavier than the Eagle sheet on the previous page) 40k 0.84-1.24M acceleration is 60s. Weight corrected to 42,000lb gives 58.9s. (Shows the intrinsically higher drag of the F-15E canopy)

F-15E with no CFT, PW-229 engines, and at 43,600lb (~4% heavier than the Eagle sheet on the previous page) 40k 0.84-1.24M acceleration is 45s. Weight corrected to 42,000lb gives 43.3s. (Shows the performance advantage of the PW-229)

F-15E with CFT, (4)AIM-7, (4)AIM-9, PW-229 engines, and at 59,600lb (~42% heavier than the Eagle sheet on the previous page) 40k 0.84-1.24M acceleration is 92s. Weight corrected to 42,000lb gives 64.83s (Shows the higher drag of the weapons and CFT)

Weight correcting the accelerations allows a more direct comparison of excess thrust and can be done since the planes are the same. Comparing the F-15C -200 and -220 times and then the F-15E -220 and -229 times it stands to reason that the F-15C with (4) AIM-7, (4) AIM-9, CL pylon, and a PW-229 motor would have a .8-1.2M acceleration time of 49.5s at 42,000lb. So while the F-15C accelerates 12.2% faster than the F-15E when they are both clean and using PW-220 motors at the same weight, once they are both loaded up and using PW-229 motors the F-15C accelerates 31% faster. This shows the wave drag difference the CFTs have.

"Spurts"

-Pilot

-Aerospace Engineer

-Army Medic

-FMS Systems Engineer