L2016-03 Serious Incident at Helsinki-Vantaa Airport on 28 October 2016

A serious incident occurred at Helsinki-Vantaa Airport when a tower controller cleared a taxiing aircraft (FIN7PN) to cross runway 22L, onto which another aircraft (SAS1706) had landed and was still in its landing roll. SAS1706 had not yet passed the intersection point of the two aircraft’s paths. The incident occurred during busy morning rush-hour traffic and the tower controller was managing several simultaneously taxiing aircraft which were waiting for clearances to cross RWY 22L from holding points Y, ZD or ZG. The tower controller mixed up the positions between the two aircraft and instead of issuing the clearance intended for the aircraft taxiing to holding point ZD the controller issued the clearance to the aircraft taxiing to holding point ZG.

The pilots of the aircraft cleared to cross the runway noticed the aircraft that was in the middle of its landing roll. They then requested the tower controller to confirm their clearance, at which time the controller corrected the mistake. The control tower did not have a technical ‘safety net’ that could have warned the controller of the incorrect decision.

Owing to the position of the terminals at Helsinki-Vantaa Airport, departing aircraft must taxi across RWY 22L when RWY 22R is in use for departures. The Aerodrome Chart designates the crossing points as Hot Spots. Finavia has evaluated the hazards of crossing an active runway in 2002.

To support tower controllers, Helsinki-Vantaa control tower uses a surface movement monitoring and positioning system (Advanced-Surface Movement Guidance and Control System, A-SMGCS), an electronic flight progress strip system and a stop bar system. According to air traffic control instructions, stop bars are not used in places where aircraft are repeatedly crossing the runway.

The work of air traffic controllers is demanding and critical to safety. They are expected to take rapid decisions and to prioritise various tasks. Their goal is to achieve safe and smoothly flowing flight operations. Many changes have recently taken place in airspace management, equipment and systems as well as in work practices. Technically oriented issues associated with the changes have taken priority in the air traffic controllers’ refresher/recurrent training, while human factors training has got less attention.

During the time of the investigation Finavia’s air navigation services were turned over to a new company, Air Navigation Services Finland Oy (ANS Finland). It started operating on 1 April 2017.

Safety Investigation Authority, Finland recommends that

• Finavia and ANS Finland, together, conduct a risk assessment on crossing an active runway during parallel runway operations at Helsinki-Vantaa Airport.

• Finavia and ANS Finland, together, ensure procurement of a technical warning system which is based on the systems presently in use at Helsinki-Vantaa control tower.

• ANS Finland safeguard sufficient and high-quality human factors (HF) training as well as the instructors’ HF competency in air traffic controllers’ refresher/recurrent training.

• ANS Finland, together with the company operating weather balloons, develop their action associated with launching the balloons so as to reduce the workload at the control tower in terms of telephone communications.

L2016-03 report (in Finnish) (pdf, 0.95 Mt) L2016-03 accimap (in Finnish) (pdf, 0.01 Mt)