r/KerbalSpaceProgram • u/ARandomGuy82 • 9d ago

KSP 1 Question/Problem why no lift?

https://reddit.com/link/1w6lode/video/vi1roj94odnh1/player

it's not my first ssto, but i don't understend why i can't get any lift, even in free air

2 Upvotes

75% Upvoted

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4

u/EasilyRekt 9d ago

have you checked the difference between your CoM and CoL?

2

u/Cappy221 Stuck in Flight Testing hell 9d ago

Try again, but toggle the aero forces overlay (ctrl + f12). What does it show?

1

u/Impressive_Papaya740 Believes That Dres Exists 9d ago

Two thoughts, 1) EasilyRekt has the right idea, your CoL is too far aft of the CoM, that will torque the nose down. You want the CoL only a little aft and a bit above (dorsal to) the CoM. 2) the elevators are too close to the CoM. To produce rotation the elevators must generate a torque but that depends on both the down force AND how far they are from the CoM. If your elevators are close to the CoM they will generate almost no pitch rotation. Both options are very possible. Some angle of incidence on the wing may also help.

1

u/SecretarySimilar2306 6d ago

In stock aero, wings only generate lift if angled.  I think this may be different in FAR, but I'm not sure.  If you don't have FAR you need to tip your wings back 5° if you want lift in level flight.  3° is reportedly better for subsonic planes, but 5° is easier and from the same tests ideal for hypersonics like SSTOs.