1. The problem statement, all variables and given/known data An a/c has an approach speed of45 m/s with descent angle of 7.1 deg. if the a/c load factor is 1.2 and constant deceleration at touch down is .25g (g=9.81).its total landing distance approx over a 15m high obstacle is 2. Relevant equations R=v/g(n-1) Sa=(h-hf)/tan( teta) Sf=Rsin(teta) hf=R(1-cos(teta) Sg=v2m/(2*F) R-radius,hf-flare height,Sa-approach dist,Sf-flare distance,Sg-ground roll S=Sa+Sf+Sg 3. The attempt at a solution well i have found value for approach and flare distance.but for ground roll im lacking mass to consider for calculation or do i miss smeting?.. any suggestion wld be helpfull.