how to turn of flying?

integer gFlying = FALSE;

default
{
   attach(key id)
   {
      if (id == llGetOwner()) {
         // Start timer to check for flight when attached
         llSetTimerEvent(0.1);
      }
      else {
         llSetForce(ZERO_VECTOR, FALSE);
         llSetTimerEvent(0.0);
      }
   }

   timer()
   {
      integer flying = llGetAgentInfo(llGetOwner()) & AGENT_FLYING;
      if (flying) {
         if (!gFlying) {
            // When start flying, impose a downward "gravity" force
            // since SL won't be applying one
            llSetForce(<0.0, 0.0, -9.8 * llGetMass()>, FALSE);
            gFlying = flying;
         }
         // Cancel out avatar's upwards movement
         vector vel = llGetVel();
         llApplyImpulse(<0.0, 0.0, -vel.z> * llGetMass(), FALSE);
      }
      else if (gFlying) {
         // Release downward force
         llSetForce(ZERO_VECTOR, FALSE);
         gFlying = flying;
      }
   }
}