A South Korean man was issued an arrest warrant last month, after he opened the emergency exit door minutes before an airplane landed.
SINGAPORE: Making exit doors on airplanes harder to open could create more problems during an actual emergency, aviation experts cautioned, in the wake of a passenger on South Korea's Asiana Airlines flight opening the door minutes before landing.
Last month, an arrest warrant was issued to the man, known as Lee, who said he felt "suffocated" and wanted to get off quickly.
Similar incidents took place on India’s IndiGo planes recently: In April, a drunk passenger was arrested for allegedly attempting to open the emergency door flap midair; while last December a passenger accidentally opened the emergency exit.
Experts told CNA such occurrences are rare and that emergency exit doors are not supposed to open midair, as the plane is pressurized.
This means the aircraft's ventilation system pumps air in to make it easier for passengers to breathe, as it climbs into the skies and the air gets thinner, said former airline executive Chow Kok Wah.
“The secondary effect ... is the pressure is higher inside than outside, which pushes the door towards the frame and therefore you cannot open the door,” he added.
For the Asiana incident, Mr. Chow, who has more than 30 years of experience in aerospace, said it was possible that the pressurization was “very, very low so that there was almost no pressure pushing on the door”, allowing the passenger to open it.
The FlightGlobal website's Asia managing editor Greg Waldron said exit doors can be opened when the aircraft is close to the ground, as part of a safety feature.
“If the plane is on the ground and there's an emergency on the aircraft like a fire, people need to be able to open the emergency exits. So yes, it is physically possible to (open the door),” he said.
“However, you're not supposed to do it unless directed to do so by the flight crew."
Most airlines require passengers occupying seats next to the emergency exit to be at least 15 years old on the date of the flight.
According to guidelines by Singapore Airlines (SIA) as well as its subsidiary Scoot, these passengers must be fully able-bodied, and capable of opening and moving quickly or reaching and passing through the emergency exit doors.
DOES BLOCKING OFF SEATS WORK?
Following the incident, Asiana Airlines announced that from May 28, some of the emergency seats on its 14 A321-200 jets will no longer be offered for sale.
But Assistant Professor Terence Fan from the Singapore Management University said: “Even if you don't assign passengers to sit there if people really intend to open the doors, they can still unbuckle their seats, walk right up to those vacant seats, sit there and open the door."
Mr. Chow, the former airline exec, added that while the airline has stopped selling its "A" seats, B and C remain available.
“(These) are not that far from the door. One step and you’re touching the door. So technically the risk is still there,” he said.
“The trade-off in aircraft design is that the more systems you put in, the more problems you create. In this case, you also have to weigh the risk in an emergency (where) I do not want anything to fail; I must open the door," Mr. Chow added.
“But to prevent silly people from opening the door, I have to put in a lot of interlocks … which if it fails, now prevents me from escaping in a real emergency.”
Mr Waldron said the safety profile of an aircraft changes when airlines start “playing around with blocking exits”.
“Changing the exit capabilities in the cabin is a very sensitive thing because if there is an emergency, people need to get out of that plane quickly. And if you reduce the number of doors, you make the doors harder to open, that could create other problems as well,” he added.
“You don't want people opening the door when they're not supposed to. But if there's an emergency, you definitely want to have people able to open the doors to help people escape and save lives.”
ADHERING TO SAFETY
In response to queries from CNA, SIA and Scoot said the safety of their customers and staff were of top priority, that both airlines adhere to safety regulations imposed by the relevant authorities, and that they ensure that operating crew are up-to-date with the latest safety protocols and procedures.
“From boarding to disembarking of a flight, we have in place (a) comprehensive set of safety measures and protocols,” an SIA spokesperson said.
Neither airline gave more details, with Scoot saying in a statement that it was a matter of "safety and security".
CNA also contacted other airlines including Jetstar, AirAsia and Cathay Pacific for more information.
Responding to CNA's queries, the Civil Aviation Authority of Singapore's (CAAS) senior director of safety regulation Alan Foo said cabin crew play a "key role" in ensuring that aircraft exit doors are not opened during flight.
"They are trained to be vigilant and to detect and respond to any unsafe situations during flight. They actively monitor aircraft exit doors when carrying out cabin services and during cabin checks in flight.
"In addition, during take-off and landing, CAAS’ regulations require Singapore air carriers to have at least one cabin crew member to be seated next to the exit doors," Mr Foo said, adding that cabin crew members act as an additional defence against any tampering of the doors by passengers.
"ONE-OFF INCIDENT"
Experts described the Asiana Airlines incident as a "one-off".
“If you look at the risks over the past 20 years, we just have not heard a lot," said Asst Prof Fan, a transport specialist. "The risk is probably not high enough to warrant a lot of intervention or action at this point.”
He added that he would be “very careful in applying or designing blanket rules or additional safeguards to arbitrarily prevent the doors from being opened”.
Moreover, retrofitting existing airplanes is a “very complex matter”, said Mr Chow, adding that any changes would entail a retraining of crew as well.
“In aviation, you have to weigh between the value you get for all the extra effort that you've to put in, and all the risk that comes with the extra effort,” he said.
Mr Waldron said airline passengers were generally “very sensible and well-behaved” - and not inclined to open emergency exit doors on a whim.
“They don't do this kind of thing ... I don't think this (incident) is part of a trend by any means."
Source from Channel News Asia
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