- Serious malfunctions on modern commercial jets exceptionally rare
- Traffic controller admits human errors occur on "daily basis," often due to language barrier
- Technology helps avert errors, but most important is trust between pilots and controllers
As authorities continue to search for the Malaysia Airlines jet that went missing on March 8, thoughts turn to air safety.
It's exceptionally rare for planes to experience malfunctions, especially serious ones. "Planes don't fall out of the sky at 36,000 feet," says CNN's aviation correspondent Richard Quest.
Even when errors do occur, most often human in nature, airlines and traffic controllers employ a vast array of procedures to ensure our safety.
Hong Kong Airlines was involved in nine incidents in which pilots apparently disregarded instructions from air traffic controllers (ATCs), including a plane taxiing onto a runway without permission and failure to follow instructions about altitude and direction.
Hong Kong's Civil Aviation Department is still investigating those incidents.
Other recent cases of miscommunication between pilots and ground controllers include:
• July 2010: The captain of an Air Blue flight disregards instructions from traffic control and crashes into mountains near Islamabad, killing 152.
• June 2013: Two Boeing 747s narrowly miss colliding over Scotland when one plane turns right and the other left -- effectively doing the opposite of ATC instructions.
• December 2013: A British Airways jumbo jet crashes into a building at Johannesburg airport when the pilot goes down the wrong taxiway.
According to Ady Dolan, an air traffic controller at London Heathrow Airport who spoke with CNN for this story, human errors between pilots and air traffic controllers occur on "a daily basis."
But while common, most errors go unnoticed and are of no threat to safety, thanks to established systems of communication and technology.
English ... but whose English?
According to Dolan, controllers at Heathrow deal with 85 airlines and 1,350 flights a day.
Controllers need to be able to communicate with pilots of many different nationalities, he says.
English is the language of aviation and vital for pilot-controller communication.
"We're lucky that English is the language of the air," says Dolan. "If English is not the pilot's first language and they only come to Heathrow occasionally, we need to afford extra care to that pilot.
"We can't speak with speed and abbreviation as we would to someone who comes here several times a day."
A pilot who often flies to China and Southeast Asia, and who spoke with CNN on condition of anonymity, says pilot