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Newbie Joined: Oct 18, 2006 Posts: 2 Status: Offline

Hi, I am looking for the drag (D), area (S) and drag coefficient (Cd) values of F16 for simple flight calculations.

The formula I use for Drag is:
D=0.5*S*p*Cd*v^2 ,

where
S : area
p: density
Cd: drag coeff.
v: velocity (tas)

Please state the units you used for the parameters.

Regards,
Tolga

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Elite Joined: Aug 19, 2004 Posts: 1089

If you can find a copy of the "HFFM manual" for Falcon 4 (an F-16 combat flight simulation), you'll find a full range of drag coefficient approximations for the F-16. You'll also find a full range of flight performance calcualtions based on this data. HFFM stands for High Fidelity Flight Models (block 15 through 52 and MLU). I develop these flight models with a French engineer. Unfortunately, the Manual is way too large to send via e-mail. You may be able to find it on some Falcon 4.0 sites though.

Newbie Joined: Oct 18, 2006 Posts: 2 Status: Offline

Hi Raptor_One, thanks for your answer. I found the HFFM-manual.rar link only at www.falcon5.nl site but the link does not work, so I could not download the manual. Can you send the manual in pieces or can you upload it to a site that I can download? You can send it in pieces to the mail address:
kilinc{at}tis{dot}havelsan{dot}com{dot}tr
thanks , regards..

Elite Joined: Aug 19, 2004 Posts: 1089

Try here...

http://www.checksix-fr.com/downloads/fa ... manual.pdf

Nice post. I don't have any references to give to find the drag in thrust or Cd values for the F-16, however this explanation applies to ANY airplane. The equation stated is correct and I will say this much, if the jet is flying at a constant airspeed, thrust does equal drag. Assuming we're cruising at a given value of thrust, the drag is equal to that much thrust regardless of configuration, externals included. The equation now changes to D=Cd(.5qVsq)(300). The 300 is our sq ft wing area. Depending on our velocity and dynamic pressure, lets take a hypothetical, say:

q=[0.00339(RHO)Vsq], V=TAS=845 ft per second which equates to 500 Knots, RHO@10,000 ft standard day = 0.7385, RHO@FL100=0.7385, thats 10,000' pressure alt. (flight levels are used from the surface on upwards instead of starting @ 180 for engineering purposes, OK?

We now have Drag, say our powerplant is delivering 10,000 lbs of thrust; 10,000=[0.7385(500)sq]/295*300*Cd, which equals: 10,000/187,754.253=Cd, Cd=.053. thats our drag coeffiecient, lift equals aircraft weight, say full fuel with center bag and some bombs, say 32K, Drag = Cd/Cl, (10,000 = 0.053/Cl, Cl = 530.000), our drag simply means the thrust setting we're developing at the nozzle. That's another thread, dude.... Shocked

Our units are as follows:
Drag = lbs
Thrust = lbs
Cd, Cl = dimensionless number
RHO = dimensionless number
q = air density, slugs per cubic foot
V = feet per second, converted to knots, divide by 6,076'

Refer to any book on aerodyn......or try NAVWEPS 00-80T-80, Aerodynamics for Aviators. Any other problem, give specific conditions. Confused

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F-16 drag value