Jowen G. Bruère-Dawson Posted November 2, 2019 Posted November 2, 2019 hi, It's been some months now that I saw on the HB F-14's section of the forum that the AIM-7 had a way too much drag. I decided to try to do a little test with the F-14 (because it's the aircraft related on the forum). Since I'm not a subject matter expert and I don't want to waste my time too much on a months old supposed bug again, I've done a fairly simple acceleration test with 3 different payloads on an F-14, here's what I found (this is not precise at all, it's just to have a rough idea of what's going on) : Other than the Sparrow/Phoenix differences, the airframes are always with 100% fuel, with full external 300gal tanks, Aim-9M on the 1A and 8A stations. Conditions are : Persian gulf, default weather, 29.92in.Hg, with no wind, all tests were conducted with autopilot and between 3050 and 3220ft ASL Full military power, from 300 to 450 IAS (in the info bar in F-2 view) - 6 Aim-54A Mk-60 : 39s - 6 Aim-7M : 35s - 2 Aim-7M under shoulder an 4x Aim-54AMk60 under fuselage : 38s Same, with full afterburner : 6x Aim-54A Mk-60 : 15s 6x Aim-7M : 16s 2x Aim-7M and 4x Aim-54A Mk-60 : 16s. Without Afterburner, from 300 to 500kts, same altitude and weather conditions : 6x Aim-54A Mk-60 : 52s 6x Aim-7M : 51s 2 Aim-7M and 4 Aim-54A Mk-60 : 53s. My thoughts about this : -All those numbers are quite close in my opinion... Which is a little bit confusing for me considering the size and weight difference between a -7M and a -54. -If we look closer, a 6xAim-7 'Cat is a little bit faster than a 6xAim-54 one, it seems pretty logic. But the difference is very small... - What I found very strange on the other hand is the fact that with 2 Aim-7 under the shoulder and 4 Phoenix under fuselage, the Tomcat is pretty much always slower than in a 6x Pheonix configuration. I tried the all Phoenix and mixed loadout 3-4 times each with the 300-450kts full burner and the 300-500kts dry power tests to have more ''data'' and it's pretty much always the same result, the mixed one, while lighter, is often slower. - The differences may seems small, but when you consider the actual weight of the aircraft, it feels like it's more important than that. Indeed the 6x Phoenix one weight 71807lbs, the 6x Sparrow one weight 68650lbs and the mixed one weight 70782lbs. The heaviest is pretty much as fast as the lightest (in average, a little bit slower), and the mixed one is often slower than the heavier... -There are many other factor to consider, some of them are human related like the time I took to go full military power without hitting the AB, when I start and stop the chronometer etc etc. -Plenty of other tests can be useful (climb rate with different payloads, same test but with different altitudes/speeds etc) but I wanted to keep it simple and see how it goes. As for drag indices, I allowed myself to copy/paste the posts of lunaticfringe in the ''AIM-54 palette weight/drag'' thread on the HB F-14 section of the forum. (https://forums.eagle.ru/showthread.php?t=252921) ''The big winners in the tunnel are Sparrow; they're indexed as 2 in the tunnel versus 6 on the stubs. The pallets incur a significant penalty in and of themselves. Drag indices are as follows: Pallets (any or all four stations): 10 AIM-54 on forward stations (3, 6): 12 each AIM-54 on rear stations (4, 5) behind AIM-54s on 3, 6: 8 each AIM-54 on 4, 5 with no AIM-54 ahead: 12 each AIM-54 stub (1, 8 ) pylon: 3 each AIM-54 on stub pylon: 12 each Also note: drag indexes for the tunnel are reduced by 5 as a whole. Thus four Sparrows in the tunnel become a total index of 3 (from 8 ), whereas four Phoenix are 45- 10+(12+8 )+(12+8 )-5.'' ''The rest of the story: Sparrow stub adapters: 2 each Sparrow on 1b, 8b: 6 each Sidewinder adapter: 1 each Sidewinder on any position: 8 each And for reference: External tanks: 11 each Tank fairings: 1 each'' Given those number (if we consider them correct, but lunaticfringe said that those numbers are included in the F14AAP-1.1), I expected a higher difference between the loadouts and I certainly didn't expected the 6x PH loadout to be often faster than the 2xSP+4xPH configuration. If you have any correction to add, or you see that I'm mistaken, please share your thoughts/advice with me. I would like the ED devs to take a look on this please to see if there are mistakes with the AIM-7 model. Thank you, have a good day.
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