I am not able to apply lenz's law?

an aeroplane having awing span of 30.48mdue north at a speed of 89.41m/s. calculate the potential diff. b/w the tips of wings over agiven locality if earth's magnetic field is 24wb/m^2&angle of dip is 60. if aeroplane is flying in northern hemisphere,what is the direction of p.d. produced?