/* Make list of all available planes.

	 * Also check to see if the previously selected plane is still available,

	 * and if not, reset selection to INVALID_ENGINE. This could be the case

	 * when planes become obsolete and are removed */

	sel_id = INVALID_ENGINE;

	for (eid = AIRCRAFT_ENGINES_INDEX; eid < AIRCRAFT_ENGINES_INDEX + NUM_AIRCRAFT_ENGINES; eid++) {

			const AircraftVehicleInfo *avi = AircraftVehInfo(eid);

			switch (bv->filter.acc_planes) {

				case HELICOPTERS_ONLY:

					if (avi->subtype != 0) continue; // if not helicopter

					break;