Beartrap (hauldown device)

The beartrap was developed in response to the difficulties encountered when attempting to land larger helicopters on smaller ships.

Until the hazard was effectively addressed, it was impractical to conduct such operations, thus multiple navies looked into various methods of easing ship-based landings under adverse conditions.

A second series of trials onboard HMCS Assiniboine (DDH 234) during the early to mid-1960s led to the beartrap being cleared for operational use with the Royal Canadian Navy during April 1967.

By the mid-1950s, many navies around the world were in the process of introducing ship-based all-weather helicopters to perform a variety of functions, from logistical support to anti-submarine warfare.

[1] However, a common difficulty that was encountered was a practical means of landing helicopters, particular larger ones, on a flight deck of a ship that was either rolling or pitching.

[2] Starting in the 1950s, the Royal Canadian Navy, which had encountered the same challenge in its early helicopter operations, undertook investigations into new methods of resolving the issue.

[7][8] Canada's Sea King replacement, the Sikorsky CH-148 Cyclone, which entered service in June 2015, is also outfitted to work with the beartrap.

[14] Typical use of the beartrap involves a helicopter hovering over the landing pad on the deck and lowering a line with an attached probe on the end.

As the pilot decreases the power, the helicopter is slowly pulled by the winch to the "low hover" position just above the deck while maintaining sync with the ship.

[1][15] The rate of pull applied by the winch is under the direct control of the landing safety officer (LSO), who can opt to increase or decrease the helicopter's descent based on moment-by-moment conditions.