The Belgian transition to NH-90

After many years of operations with the Alouette III and Sea King the Belgian military is currently conversing to the NH-90NFH. In August 2015 the NH-90NFH received initial operational capability for Search and Rescue (SAR) missions within the Belgian Air Component. Only a few days later the first successful mission was flown. This however means not that the transition period was over yet. The NH-90NFH is not operational for frigate operations at the moment. The end of the transition period is set for 2018 when the Alouette III and Sea King will be phased out. Till then some of the missions will still be carried out by the Alouette III and Sea King.


The backbone of the Belgian maritime helicopter force consists of two types for the last decades. The Sud Aviation SA316B Alouette III, in service since 1971 and the Westland Sea King Mk48 in service since 1976. Both types are active in two different roles. The main task of the Alouette is that of frigate helicopter on board of the Belgian Navy ships. Therefore, the Alouette was part of the Belgian Navy until 2004. The primary role of the Sea King is SAR in the Belgian part of the North Sea. Today both helicopters are operated by the 40th squadron of the Belgian Air Component.


After many years of service for both the Sea King and Alouette III it’s time for replacement. The reason for replacement is clear, both the Sea King and Alouette are outdated and at the end of their technical life. In 2006 Belgiaum decided to become partner in the NH-90 project and decided to buy eight helicopters, with an option for another two, a year later. The purchase was evenly distributed between two subtypes, namely four NH-90TTH’s (Tactial Transport Helicopter) and four NH-90NFH’s (NATO Frigate Helicopters). The latter where to replace both the Alouette III and Sea King.  

The NH90 is replacing this forthy year old Allouette III helicopter which is currently used as frigate helicopter.

Naval operations

The introduction of the NH-90NFH is a big improvement, especially for the Belgian Navy. There is an immense difference between an Alouette III and a NH-90, both operationally as well as capability wise. Contrary to the Alouette, the NH-90 is suitable for anti-submarine warfare (ASW) and anti-surface warfare (ASuW). To make the task easier the NH-90NFH can use its radar and Forward Looking Infra-Red (FLIR) for ASuW. This means a big improvement for both the navy as the Alouette III simple lacks all these items. For ASW the NH-90 can be adapted with an ASW station and dipping sonar to locate submarines. It is even possible to put torpedoes under the helicopter to attack submarines but Belgium did not acquire any torpedoes yet.

To make the navy frigates suitable for the much larger and heavier NH-90 the ship’s helicopter decks have been enlarged and strengthened. Furthermore the hangar of the ship has been enlarged to fit the helicopter.

SAR Operations

For SAR operations the differences between the Sea King and NH-90NFH are small. One of the main improvements is the speed of the NH-90 in comparison with the Sea King. Both the cruise speed and maximum speed is much higher than that of the Sea King. For example the maximum speed of a NH-90 is 50 knots higher than that of a Sea King. The range of the NH-90 is slightly lower but due to the higher speed it will not have impact on the time over target of the NH-90. Besides that due to the central location of Koksijde Airbase the Sea King almost never flew with full fuel tanks to save weight. Despite the advantages, the NH-90 has also a big disadvantage. The inside of the NH-90 is much smaller than a Sea King. Most of the work has to be done on the knees because the helicopter is too low to stand. This is makes the work for the crew in the back harder.  Another disadvantage is the enormous downwash of the NH-90. Because of the difference in size and engine power the downwash of the NH-90 is much larger than from its predecessors. A bigger downwash is not very comfortable to work in and requires more skills from for example the winch operator.

One of the pilots posing in front of the NH-90 helicopter. 

Area of responsibility

The Belgian SAR unit is responsible for the Belgian part of the North Sea. Much of the shipping traffic through the Channel passes through Belgian waters, making it a busy shipping lane. Besides that the Belgian Air Force also assists their neighbouring countries. Due to the central location of Koksijde Airbase many missions have been carried out in French, Dutch or Britain waters. The Belgian Air Force has one helicopter on standby 24 hours a day, seven days a week. During the transition period the Sea King and NH-90 share their missions increasing the share of the NH-90 over time. With the limited amount of crews available it is hard to keep a crew available at any time. A regular SAR shift will last for 24 hours. The crews sleep on base and have 45 minutes to respond to a call at night. During daytime the time required to take off is 15 minutes.


Most calls come in at the Rescue Sub Centre (RSC) on Koksijde airbase. For each request the Centre will decide if they can handle it and is allowed to handle . When the RSC decides it is a go they will scramble the SAR crew. The crew gets briefed by the RSC and after take-off the RSC coordinates the mission and keeps the helicopter informed. The RSC has radar images of all flying and sailing traffic in the area. With this information the RSC can give the crew valuable information on the mission status. A normal search operation will often start at the most probable point which has been calculated by a computer. The RSC calculates this point based on the time and location of the call and the current, wave and wind information. With the introduction of the NH-90 the RSC can respond quicker due to the higher flying speed of the helicopter. This can make a live saving difference in the future.


It will take until approximately 2019 before the NH-90 becomes the sole maritime helicopter for the Belgian Air Component. The Sea King is set to retire in 2018 after 42 years of active duty. The Alouette III will fly even longer. This helicopter is set to retire in 2019 after 48 years of active duty. By then the NH-90 will be the only  use of Koksijde Airbase. In the past there where some rumours about a possible closure of the airbase. A few years ago however, the decision was made to keep the base open for helicopter operations. This means that NH-90NFH will be based at Koksijde Airbase into the future. With the combination of both SAR helicopters and the RSC, Koksijde Airbase stay to play a central role in safe maritime traffic through the Belgian part of the Channel. It is for sure that the NH-90 will be the key player in this role.

We would like to thank Gilze-Rijen Aviation Society (GRAS) and the Belgian Air Force for making this visit possible.