Add hot water to gelatin mix; stir until completely dissolved. Add lemonade concentrate; stir until thawed. Set aside to cool. (Do not refrigerate.)
Beat heavy cream with mixer fitted with wire whip attachment on medium speed until stiff peaks form. Temper warmed gelatin mixture into a portion of the cream then beat into remaining cream.
Spoon 3 cups of the mixture into each pie crust.
Refrigerate 1 hour or until firm.