Experts investigating Tokyo airplane crash

Crash ‘could have been caused by runway incursion’

Former air traffic controller Michele Robson has said initial information suggests the collision was caused by a runway incursion – such as the Coast Guard aircraft entering the runway when it shouldn’t have. 

She said there “needs to be proper investigation” before conclusions are drawn, but a series of factors meant the larger Japan Airlines plane might not have known the Coast Guard aircraft was on the runway. 

One such factor is that because it was dark, there was less visibility both from the air traffic control tower and for the Japan Airlines pilot. 

Tokyo International Airport has “all the safety equipment you’d expect at major airport”, including a runway incursion alert system. 

But Ms Robson said the alert likely wouldn’t have set off because the Japan Airlines flight was not on the runway when the Coast Guard plane entered. 

She also said it appeared the Coast Guard aircraft did not have an ADS-B transponder, which is used to transmit highly accurate information about an aircraft’s position to ground controllers and directly to other aircraft.

Normally you would expect all flights from a large international airport to carry these transponders, Ms Robson said, but this appeared to be an unusual situation where the Coast Guard flight was travelling to help with earthquake relief. 

Ms Robson said the lack of ADS-B transponder would have made the Coast Guard plane “less visible” if it didn’t do what it was expected it would do. 

The “split second timing” would have meant it “wouldn’t have taken more than a few seconds for the aircraft to get on the runway as the other plane was landing”. 

“At that point, with a large passenger jet, it probably wouldn’t have seen the smaller aircraft in the dark,” she said. 

The former air traffic controller said this is “one of the most dangerous factors in terms of airport incidents”. 

Another factor may have been that the airport uses a “mixed mode” runway – meaning both departures and arrivals use the same runways. 

Although they still have a “generally good safety record”, it is safer to use separate runways for departures and arrivals – as is the case at Heathrow Airport, for example. 

International Air Transport Association offers thoughts

The IATA has said its “thoughts are with” the passengers and crew of both the Japan Airlines flight and the Coast Guard aircraft.

“The last two days have been difficult for Japan,” it said, referencing the New Year’s Day earthquake that killed at least 48 people. 

“Our thoughts are with the people of Japan during these challenging times.” 

Pilot on Coast Guard flight was injured

Japan’s transport minister has confirmed the pilot of the Coast Guard flight was injured. 

The pilot was the only person on board the smaller plane to survive. 

Minister Tetsuo Saito said the airport is currently closed while the collision is under investigation by aviation safety investigators and police.

However, there are hopes it can be reopened by tomorrow or even sooner. 

He added that officials are doing their best to prevent any delays to earthquake relief.

The Coast Guard flight had been headed to an earthquake-hit region of Japan.