[Sascha]

here we go (with Stigg's function)

pawn Код:

public OnGameModeInit()
{
    SetTimer("CheckAircrafts", 500, true);
    return 1;
}

forward CheckAircrafts();
public CheckAircrafts()
{
    for(new i=0; i<GetMaxPlayers(); i++)
    {
        if(IsPlayerConnected(i) && IsPlayerInAnyVehicle(i))
        {
            if(IsAFlyingVehicle(GetPlayerVehicleID(playerid)))
            {
                new Float:hp;
                GetVehicleHealth(GetPlayerVehicleID(playerid), hp);
                if(hp < 200)
                {
                    YOUR WARN CODE HERE
                }
            }
        }
    }
    return 1;
}

stock IsAFlyingVehicle(vehicleid)
{
  switch(GetVehicleModel(vehicleid))
  {
    case
        460,464,476,511,512,513,519,520,553,577,592,593,//flying vehicle models
        417,425,447,465,469,487,488,497,501,548,563:
    return true;
  }
  return false;
}