MIL-R-85111A

Abstract

This specification establishes the performance, design, development and test requirements for the helicopter Recovery Assist, Securing and Traversing (RAST) System. <b><u>Intended Use:</u></b> The RAST system to be supplied in accordance with this specification is intended to provide the capability to operate LAMPS MK III helicopters in adverse weather conditions from the small flight decks of LAMPS MK III ships experiencing extreme motions. A requirement exists to provide the capability to operate helicopters in all weather conditions, up to and including upper Sea State 5, from the decks of nonaviation ships operating within the LAMPS mission profile. It is anticipated that helicopter recovery operations aboard LAMPS ships will be conducted in the following manner. The helicopter will approach from astern of the ship, flying to arrive in a hover position at a safe altitude above the flight deck. After the messenger cable has been lowered to within reach, the ship's personnel ground the cable and attach the messenger link to the recovery assist cable which had previously been faked out on the deck. The messenger cable will be reeled up causing the recovery assist cable to lock into the main probe of the helicopter. The recovery assist cable is then reeled in until taut whereupon the control system automatically maintains a constant hover tension. To optimize the guiding effect of the cable, the hover altitude is decreased to an acceptable minimum and the cable tension is increased as desired for the existing environmental conditions. During a quiescent period, the LSO assists the pilot to land and actuates the RSD to capture the helicopter main probe. The pilot actuates the tail probe which engages the tail grid. Following the usual helicopter post flight operations, the tailguide winch cables are manually attached, the tail probe is retracted, and the recovery assist cable is released. Using a combination of tailguiding and traversing controls, the helicopter is maneuvered to the required position for traversing. With the tailguide winch cables removed, the helicopter can be traversed into the hangar. After the helicopter has been traversed to the takeoff position and readied for flight, the tail probe may be retracted leaving the helicopter secured to the RSD by the main probe alone. When suitable conditions for takeoff are obtained, the LSO operates the console control to disengage the RSD and the helicopter is free to takeoff. When ship motions are not too extreme and with due consideration to other environmental and atmospheric factors, the pilot may land without the assistance of the recovery assist cable. During untethered operations, the LSO guides the pilot so that the helicopter lands with the main probe inside the RSD; subsequent actions are then the same as for tethered landings. Although outfitted with a recovery system, LAMPS ships will also conduct flight operations with unequipped helicopters. In this situation, the RSD will be traversed away from the landing area. <br>