NLR tackles helicopter brownouts

Due to blowing sand, a helicopter pilot’s in-flight visibility can be severely restricted during landings in deserts.

At the request of the Dutch Ministry of Defence, the National Aerospace Laboratory (NLR) has recently started working on finding solutions to support pilots during these precarious desert landings. 

Missions in Afghanistan and Iraq have made the issue of brownouts a hot topic in the international aviation community. Owing to the clouds of sand and dust that helicopters generate when landing, pilots are often partially or totally blinded during the final seconds before landing. This can lead to potentially dangerous situations.

The Ministry of Defence has therefore asked NLR to recommend feasible and affordable solutions for the helicopters the Dutch military deploys during tactical operations, namely, for its transport helicopters, such as the Chinook.

One possible solution NLR will study is the use of Helmet Mounted Displays (HMD), which are helmets equipped with small displays positioned in the pilots’ sightlines. Projected onto this display are symbols and sensor information, which pilots can see in addition to the actual surroundings they are operating in.

The information projected onto the HMD is what the pilots would see if they were operating in clear conditions, but also if dust clouds have severely restricted their sight. This new technology will first be tested in the Helicopter Pilot Station (HPS), the NLR’s helicopter simulator.

The United Kingdom, the United States and Germany are also actively engaged in trying to solve the problem of brownouts. Studies of, for example, dust penetrating sensors – sensors that can see through dust and sand – are now being conducted, as well as computer-generated images of the landing area for the pilots in the cockpits.

To date however no ready-made solutions have yet been found; hence, the Ministry of Defence has asked NLR to evaluate the suitability of the various international technological developments for the Dutch situation – that is, with a view towards the types of helicopters the Dutch military uses and the kinds of missions it conducts. 

In the fields of helicopters, avionics, military operations and human performance, the NLR possesses the ideal mix of knowledge and experience with which to complete this assignment for the Ministry of Defence. NLR will test promising solutions for helicopter brownouts in its recently upgraded Helicopter Pilot Station (HPS) simulator.

By Netherlands National Aerospace Laboratory / Nationaal Lucht- en Ruimtevaartlaboratorium