To lift off, Cl × ρ x v2 x A / 2 > G (m1×m2) / r2 must be true.It can then be rearranged to Fnet = Cl × ρ x v2 x A / 2 - G (m1×m2) / r2 to calculate the net force when taking off.
Cl × ρ x v2 x A / 2 > G (m1×m2) / r2
Fnet = Cl × ρ x v2 x A / 2 - G (m1×m2) / r2
NaN N
G = 6.674×10−11 m3/(kg s2)