Terrain Avoidance Warning System (TAWS) Will Not Overcome Inadequate Flight Planning and Operation

The announcement by the National Transportation Safety Board (NTSB) that the Sikorsky S-76 which crashed with Kobe Bryant, his daughter and seven other people on board did not have a Terrain Avoidance Warning System (TAWS) installed has caught the attention of the media.  Some have even suggested that if the aircraft had been equipped with such a system the crash would not have happened.   Response:  MAYBE.

It must first be said that we do not yet know what we need to know to conclude that the pilot was flying a healthy aircraft, did not suffer some in-flight incapacitation, or something else happened that caused him to fly close to terrain. Until we have answers about the aircraft, its systems, and the health of the pilot, we cannot conclude that this was a case of Controlled Flight Into Terrain, known as CFIT.

TAWS senses the aircraft position, speed and direction data from the aircraft’s GPS, adds the aircraft’s altitude and configuration information, and then compares them to a highly accurate database of the relevant  terrain and manmade obstacles. TAWS superimposes the aircraft’s position and tracking information and issues relevant alerts for the pilot to take appropriate action to prevent CFIT.  Of course, it is then up to the pilot to take appropriate action.

I would never argue against any system that enhances safety and TAWS certainly meets that criterion. Such a system should be mandatory on all helicopters aircraft used in commercial operations—not just medical helicopters.

But TAWS only helps when the helicopter is already in or approaching a precarious situation.  It would be better, obviously, if the helicopter were not close enough to terrain or other obstacles that the TAWS would activate. This means good decision-making not only in the air but also on the ground prior to departure.

Here the analysis of helicopter accidents by the IHST discussed in a previous post is instructive.  Among the SEVEN factors cited for causes of errors and violations are THREE that speak to operational error:

• Lack of attention to the training in decision-making for departure taking into account the possible complications of flight conditions
• Weak safety culture
• Deficiencies in training and not transfer of skills, professional care and the ability to make decisions

Each of these addresses factors that can result in poor operational decision-making and judgment.  They point to situations on the ground that can directly cause safety situations in the air.  By then, it could be too late.

Once everyone shows up at the airport or the heliport there is great pressure to launch.  People want to go.  But good judgment, and courage, often demand that air transportation be cancelled in favor of ground transportation.  This has shown to be true in helicopter medical operations and is equally true in other commercial helicopter operations.  With proper mission analysis and planning, reliance on TAWS is greatly reduced.