Doing some flight tests
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Wiki says F-16c service ceiling 15000+ fts in clean configuration. What does clean configuration mean? Do AA missiles only configuration count as “clean”. How high can I go with only 5 AIM120s and 1 AIM9? Do I need AF to maintain this alt?
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Are you sure about the 15000+ service ceiling?
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I think you mean to say 50,000+. Clean means still in Cat I. Mostly means no air to ground stores, and no wingtanks.
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This post is deleted! -
+1…That’s what I found also.
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Probably 15,000m. Units!
Ceiling is approximately 1000’ different at 100 DI than 0 DI. Two AIM-120 on wingtips is DI=9 so assume the DI=0 line. Gross weight matters much more. Every 3,000 lbs. is ~1000’. After DI=250 it matters much more (250 vs 350 is ~3,000’).
49,213’ is possible under MIL with very low DI (probably 25 or less). But the big catch is GW which is 21-20 klb. maximum. This is for combat ceiling (500 fpm Ps), you can add 1,340’ for service ceiling (100 fpm Ps) or half this much for cruise ceiling (300 fpm Ps).
With MAXAB the ceiling is about 6,000’ more but of course is very short.
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Yeah, it was a typo. I meant 15k meters, not feet. Please don’t bombard me with technical abbreviations. What is DI? Drag Index? What about fpm ps? If 2 aim120s is 9 then 4 AAMs is about less than 20. Then I have full internal tank, no wing bags. Then, I can barely make 49k fts with full MIL?
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Yes drag index. Ps is “specific Power” which is a measure of energy-add potential rate (expressed as a climb rate, feet per minute climb). It is common to make definitions about ceiling not at absolute (Ps = 0) but a little less (500 fpm, 300 fpm, 100 fpm). At full fuel, no chance. If you are on the last 1000 lbs. or so yes your climb rate through 49,000 should be ~500 fpm at this weight.
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More correctly, Ps is “Specific Excess Power”. If you have excess power at a given flight condition, you can “power through” that condition - like being able to zoom through an advertized ceiling or perform excursions from balanced flight with less penalty.
http://www-mdp.eng.cam.ac.uk/web/library/enginfo/aerothermal_dvd_only/aero/perf/climb/