Dalia flies an ultralight plane with a tailwind to a nearby town in 1/3 of an hour. on the return trip, she travels the same distance in 3/5 of an hour. what is the average rate of speed of the wind and the average rate of speed of the plane? initial trip: return trip: let x be the average airspeed of the plane. let y be the average wind speed. initial trip: 18 = (x + y) return trip: 18 = (x – y) dalia had an average airspeed of miles per hour. the average wind speed was miles per hour.