MH370’s takeoff, as far as we know, was normal in every respect. Preflights were completed by the pilot and copilot, cabin crews helped seat the 227 passengers from 14 nations who were flying to Beijing. A few passengers are known to have made phone calls, texted, and emailed loved ones and associates wherever they happened to be around the world prior to takeoff. Even “no-shows” were less than 2%, half of what they would normally have been. All was well.
The aircraft pushed away from the gate normally, taxied to the runway normally, took off into the midnight sky normally. Exchanges between the pilots and ATC were normal. Everything was normal.
The plane’s flightpath went according to plan as the Boeing 777 lifted off and climbed to altitude. All systems, as far as anyone knows, were working as they should have. ADS-B, the Automatic Dependent Surveillance-Broadcast, reported the plane’s position and altitude 40 times between Kuala Lumpur International and Waypoint IGARI in the Gulf of Thailand.
The first ADS-B record was initiated at 16:42:47 with Kuala Lumpur’s Subang Airport. A new radar contact record was created roughly every minute. At 16:58:42, ADS-B records were logged by Penang International Airport. Then, as the plane flew northeast across the Malaysian Peninsula, Kuala Terengganu logged 3 records, then finally, Kota Bharu, northeast of Kuala Lumpur on the Gulf of Thailand, logged the remaining 16 contacts. The last ADS-B log entry was at 17:21:03 at Kota Bharu – 38 minutes, 16 seconds after the first. Everything, as far as anyone knows, was still normal.
The moment MH370 disappeared was not immediately recognized as the disaster it was about to become. It couldn’t have been because radar and communication stopped while the plane was passing through an air traffic control black hole. Normally, air traffic control responsibility for each aircraft is handed from controller to controller directly or via automated affirmative transfer. But when shared radar coverage doesn’t exist, such as between Malaysia and Vietnam in the middle of the Gulf of Thailand, it often falls to the pilot to contact the next ATC once it returns to active radar contact within radio range.
For MH370, air traffic control responsibility was relinquished by Malaysia near Waypoint IGARI. It was beyond radar range at that moment and would remain in a radar limbo, as a rule, for three or four minutes before Ho Chi Minh City acquired it. That is the way it works. There was still nothing unusual about anything we know at that point.
In today’s commercial aircraft world, life is a parade of small anomalies punctuated by medium-size anomalies, but seldom by large anomalies: navigation has a hiccup, but you work around it; a tire blows on takeoff or landing, but you work around it; a passenger goes berserk, but you work through it. Training and experience help keep things running smoothly, and that usually helps keep small and medium sized anomalies from becoming life-threatening emergencies.
But the anomaly in the case of MH370, whatever it was, wasn’t small. Moreover, far below on the ground the painfully slow realization by air traffic controllers and others that a large commercial airliner had vanished unfolded like a slow-motion landslide: something might be amiss with that plane …; something almost surely seems amiss with MH370 …; something definitely is happening that shouldn’t be happening…!
At 17:30 UTC, nine minutes after radar contact was lost, Vietnamese ATC asked another plane under its control to contact MH370. The pilot of the plane that tried to make contact, another MAS plane on a flight to Japan, reported that MH370 responded, but that the reply was indistinct mumbling and radio static. It is not known if that pilot was actually in contact, even briefly, with MH370.
Then, at 17:37 UTC, it was later learned, a scheduled ACARS transmission was not received. That was the first absolutely clear indication that something was seriously amiss. Loss of radar contact, failure to get positive transfer to Ho Chi Minh City, and failure to get an articulate response on an emergency frequency had alternative explanations. They were potentially small anomalies. But it was the failure of ACARS to report as scheduled that indicated beyond question something was seriously wrong aboard MH370. Sadly, it could not have been known at the time by ATC or anyone else who wasn’t on that plane.