A prosecutor in Marseille has said the Germanwings plane may have been deliberately crashed by the co-pilot, with the pilot locked out of the cockpit. How could this situation arise?
After 9/11, changes were made to the security of cockpits in an effort to make hijackings more difficult. According to the US Federal Aviation Administration, doors should typically be tough enough to withstand a grenade blast. They are usually left locked throughout the flight.
Cockpit security systems are supposed to allow a pilot the ability to access the cockpit. But access can be deliberately denied from within the cockpit.
Cockpit doors on an Airbus – according to this video understood to have been produced by the company – have three modes that are operated from the pilots’ seats: unlock, normal, lock.
In the event of whoever is in the cockpit being incapacitated there is a touchpad that will allow cabin crew who know the code to enter.
In “normal” mode the cockpit is locked but can be accessed – after a 30-second delay – by touchpad should the cabin crew get no response from inside.
“Unlocked” mode is what a pilot would use to open the door for a colleague returning from the toilet.
“Locked” means the locking mechanism ignores the touchpad entry code and remains locked for five minutes (it can be repeated). It’s easy to see how this would be used to prevent hijackers who have managed to get hold of the code from cabin crew from entering the cockpit.
Some planes may have a screen to tell the pilots who is outside the cockpit door.
If a pilot is unable to access the cockpit, it suggests that his colleague has denied entry.
There is also the question of how many people must be in the cockpit at any one time. Flight attendant Heather Poole tweeted: “In the US a flight attendant always goes into the cockpit whenever a pilot takes a break/leaves.”
In contrast, Germanwings cockpit protocols are in line with rules established by the German aviation safety authority, the Luftfahrt Bundesamt. This dictates that when there are two crew, one can leave the cockpit – but only for the absolute minimum time.
Other airlines have a “rule of two”, where if a pilot leaves the cockpit for any length of time, another crew member must replace them. However, this is not the case with Lufthansa or other major airlines.
The pilot had been with the airline group for 10 years and has more than 6,000 flying hours. The co-pilot joined the airline in 2013 and had 650 flying hours.
Helios Airways Flight 522 (Aug. 14, 2005)
The Boeing 737 crashed in the mountains near Athens, killing all 121 on board, after the co-pilots became incapacitated after they mistook an in-flight depressurization — which deprives the plane of oxygen — for an air-conditioning malfunction. Moments before the plane exhausted its fuel, a flight attendant had managed to enter the locked cockpit using an emergency code and attempted unsuccessfully to control the plane. The Guardian reported in 2006 that on this flight, only the senior steward had been permitted to know the code, raising questions of whether open doors — or less protected doors — would have allowed the flight attendant to reach the cockpit sooner. (It is not known how the flight attendant obtained the code.)
Mozambique Airlines Flight 470 (Nov. 29, 2013)
The Embraer 190 crashed in Namibia en route to Angola after descending rapidly from an altitude of 38,000 ft., killing all 33 passengers and crew. Investigators believe the captain had a “clear intention” to crash the jet. “[Moments before the crash] you can hear low and high-intensity alarm signals and repeated beating against the door with demands to come into the cockpit,” a Mozambican Civil Aviation Institute official said after the jet’s cockpit voice recorder was retrieved — but the person banging on the cockpit door could not get inside.
Air New Zealand Flight 176 (May 21, 2014)
Midflight, the captain of a Boeing 777 carrying 303 people locked the first officer out of the cockpit after they had an argument over a take-off delay, the New Zealand Herald reported. The captain did not immediately respond to requests from the crew to open the door, alarming the first officer and cabin crew. After two minutes, the first officer used “an alternative method” to access the cockpit, the airline said, though it did not specify what method for security reasons. After the incident, both pilots were ordered to receive counseling and training.
Pacific Southwest Airlines Flight 1771 (Dec. 7, 1987)
This routine flight between Los Angeles and San Francisco crashed after a newly terminated employee, who had brought a gun on board the jet, shot five people. The plane entered a nosedive, resulting in the deaths of all 43 people aboard, investigators said. Analysis of the cockpit voice recorder suggests a flight attendant had opened the cockpit door to warn the pilot that a gunshot had been fired in the cabin, after which the suspect shot the woman and both pilots and seized controls. Though fortified cockpit security may have prevented the crash, investigators were concerned primarily with how exactly the employee managed to board the plane with a gun. They attributed the incident to a now-defunct policy that had allowed airline employees to bypass normal security if they displayed credentials, which the suspect had not surrendered upon termination.
JetBlue Flight 191 (March 27, 2012)
The 100-some passengers on the New York to Las Vegas flight had a scare when the captain began to behave erratically, telling the first officer things like “we’re not going to Vegas,” according to an FBI statement. When the captain left the cockpit to go to the lavatory, the first officer asked a flight attendant to bring an off-duty captain aboard the plane into the cockpit. The two pilots locked the door, ordering passengers on the intercom to restrain the on-duty captain as he attempted to enter the cockpit with his emergency access code. All on board were unharmed.
United Airlines Flight 1074 (March 17, 2015)
A flight headed from D.C. to Denver returned to the airport 20 minutes into the flight after a passenger became violent and ran toward the cockpit, the airline said. The man was immediately restrained by other passengers while the pilot safely landed the Boeing 737, carrying 33 passengers and six crew. During the process, the pilot reassured the controllers that the cockpit was locked, according to recordings of the radio communications from the flight.
Source – www.bbc.com/news
www.time.com