After several years of delays Denmark has decided to buy nine American MH-60R Seahawk anti-submarine helicopters. Two years ago Denmark was planning to buy twelve MH-60Rs. This was interrupted by money shortages and the need to also check out the competing British AW159. The MH-60R won the competition and money was found to make the purchase. This was helped along by the growing problems with the elderly Lynx helicopters the navy was currently using.
This MH-60R is a navalized version of the 11 ton U.S. Army UH-60. Denmark will use the MH-60Rs for search and rescues, as well as for ASW (Anti-Submarine Warfare). The latter involves using computers, sonar, and radar to search for submarines. This work involves staring at a screen most of the time, while manipulating the sensors and computers to detect and locate subs. Once you have a solid location fix, you can launch a torpedo and sink the enemy vessel.
The MH-60R uses a sonar that operates in active (broadcasting) and passive (just listening) mode. The sonar system consists of a dipping sonar and sonobuoys, that are dropped and communicate wirelessly. The dipping sonar is lowered into the water from the helicopter using a 806 meter (2,500 foot) cable and winch. The MH-60R is also equipped with a radar system for detecting subs on the surface or just beneath the surface (with only the periscope or snorkel, which provides air for the diesel engine, and gets rid of the exhaust fumes).
For search and rescue work the sonar and all its associated electronics is removed but the radar stays. The MH-60 can hover low enough to deploy a line to people in the water and winch them aboard.
Denmark has long used British helicopters and still has bought four Westland EG101 Merlins, along with older Super Lynx models. The Lynxs were refurbished but are still so worn out that less than half of them are available for service at any one time.