Swedish NH90 Now Ready for Night Sub Hunting

Försvarsmakten, October 20, 2023 - by Per Åhlin - For several years, the Helicopter Flotilla's sea operations squadron has been working on developing a procedure for hunting submarines in darkness or zero visibility.

Now the procedure has been approved and crews have been trained. During Marine exercise Autumn 2023, the ability was included for the first time in an exercise context.

Hunting submarines in the Baltic Sea is a difficult task due to factors such as temperature layers and bottom conditions. But it is nevertheless one of Sweden's military parade branches.

The navy is responsible for monitoring and being able to assert Swedish maritime territory every day, all year round, both on the surface and below. They have the Air Force's maritime operational helicopters to help them, which contribute in both surface surveillance and submarine hunting. The helicopter's strength is being able to move quickly to search areas and surprise the opponent. In this way, the flying units complement the endurance of the ships.

Since the Swedish Armed Forces began hunting submarines by helicopter again in 2016, there has been a lack of an approved flight operational procedure for performing after dark and in poorer weather. This is because it is pitch black out at sea and there is thus a lack of visual references. The crew can therefore determine neither height nor flight position visually, but must rely entirely on instruments when descending towards the water surface.

Naval exercise in the Baltic

Since Sweden is located in a part of the world where it is dark for large parts of the year, it has been a priority to develop a procedure to operate after dark or when visibility is zero. This procedure was approved in 2021 and since then crews of the Helicopter Flotilla's third squadron have been trained and trained on the elements included in the procedure. During Marine exercise Autumn 2023, which was carried out in the Stockholm archipelago and the Gotska lake on October 11–18, the new capability was included for the first time in a larger exercise.

The platform, sensors and the procedure we had for submarine hunting in daylight have worked outstandingly since we reintroduced the capability in 2016. Both systems and crews have long been mature to develop the capability also in the dark, says division chief Major Meijer, who has been driving the work with the new the procedure.

We have nevertheless approached this procedure thoughtfully with a great measure of humility and caution while maintaining a certain momentum in the propulsion. As always, it is the highest priority that everyone comes home safe and sound after each flight, but of course it means increased risks when we do not include visual references, continues the division manager.

The new capability also means that the naval operational helicopter forces are no longer as weather constrained as the procedure can also be used when the weather makes it impossible to maintain visual references. It provides enhanced capabilities in other flight operational procedures that are preceded by a descent over water surface.

There are many people who have put a lot of effort into this over several years and now we are finally here. At all levels, from the head of the air force to the head of the navy and down the ranks, many have been involved. Now we have one more card to play to deliver operational effect in both the Air Force and the Navy, says Henrik Fridolfsson, deputy squadron commander of the third squadron at the Helicopter Flotilla.