II might as well post this now, because I won't have a chance to update it if the mystery of Malaysian Airlines 370 is solved in the next few days. I don't have any special insights about the disappearance of an entire Boeing 777, but as a pilot I have to wonder about it.
First off, despite what movies like Airport '77 depict, an airplane that crashes into the sea doesn't slip whole and undetected under the waves. With considerable skill, or even questionable skill and some luck, it could alight on the surface of the water without substantial damage. Handled as if it were being landed on land, an airplane can skim over the surface of the water the way a skipped pebble or a snowmobile does. (Unlike the snowmobile, an airplane doesn't immediately sink, because the fuselage is full of air, and buoyant). No sane person would deliberately ditch an aircraft without a substantial emergency, because if something goes slightly wrong, the picture is substantially different. The video below is of a hijacked Ethiopian Airlines aircraft that was out of fuel. The captain was trying to ditch it while fighting with the hijackers. Even that fuselage stayed afloat for a reasonable amount of time, and many of the deaths were not due to crash injuries, but because passengers inflated their life vests before exiting the aircraft, impeding evacuation.
There's a post being shared on Facebook that purports to show the aircraft recovered, but you can tell from the still that it's actually a Lion Air landing accident from last year. Don't click that one because it's probably a virus.
When an airplane comes into contact with it, water is really quite a bit like ground. Do it in landing configuration, descending towards the water at a shallow, about three degree angle, then touching down wings level, slightly nose up and it is quite survivable. Do it at high speed, or inverted, or any other way that doesn't involve control at a low descent rate, and the result is catastrophic. Swiss Air 111 hit the water 20 degree nosedive, and at a bank turn angle of 110 degrees, and disintegrated into millions of pieces. Only one of the passengers was visually identifiable. Alaska Airlines 261 was a similar story. Many of the millions of pieces that make up an airliner and its contents float, so the debris is visible on the surface and drifts ashore. Jet fuel is oily, and floats on water leaving a visible slick. Also both those crews were in contact with air traffic control during the sequence that led to the crash.
When an aircraft suddenly disappears from radar and stops transmitting, one good guess is that it broke up in midair. But when that happens the pieces are in the water in roughly the area where the radar track stopped, and the last week has seen ships, helicopters satellites and and airplanes tasked to search that area with no results. Plus substantial other evidence exists that the airplane did not explode, crash, alight or otherwise make contact with the water in the area they've been looking for it. SATCOM, an automated system on board the aircraft, and one a very diligent Boeing pilot of my acquaintance says he doesn't know how to turn off, continued sending transmissions. It's a passive system that pings about once an hour, sending what's basically a "ready to transmit" signal but no data links were opened, because the companies involved had not subscribed to that level of service from the satellite operator.
Here's what I have gleaned of the timeline. Times are Malaysian local.
- 12:41 a.m. Take off
- 1:07 a.m. The ACARS data transmission system stopped communicating. ACARS is a two-way data transmission system in the cockpit. The pilots can use it to request weather data and the airline will use it to send them connecting flight information, and even to update the flight management system. It automatically transmits some data on phase of flight and things like fuel status and engine performance, so the airline can detect a need for maintenance before it is urgent. It can also be used for communication with ATC, but as far as I know is generally only used with ground controllers to get the complex initial clearance for a flight. It might be used in flight for a complex rerouting, but I don't know. Check the comments to see if one of my more knowledgeable readers does. The ACARS system can be turned off from the cockpit.
- 1:21 a.m. The crew is 'handed-off' by Malaysian ATC. That is they are told to contact the next controller on a specific frequency. They reply normally to this call, implying that they will comply, but do not call the Vietnam ATC.
- 1:21 a.m. The transponder is turned off. The transponder is a simple device that works in concert with ATC radar. Before take-off ATC assigns the airplane a four digit code, which the pilot sets on the transponder. When it receives a ping from radar, it sends back a signal encoded with the aircraft altitude and the four digit code. that the pilot has set on the device. The ATC computers match the code with the aircraft type and destination in its flight plan, plus calculate and display a speed based on consecutive returns. If an aircraft does not have a working transponder, ATC may still see the aircraft on radar, but it is a "primary target." The transponder can be turned off from the cockpit. Transponders malfunction pretty frequently, and an aircraft like the B777 probably has two, for backup and to facilitate changing codes without an interruption in radar track.
- 1:22 a.m. Vietnam ATC expect a check in from the airplane but instead the radar track shows an almost 180 degree turn.
- 1:38 a.m. Civilian radar lose primary target. Without the positive identification of the transponder reply, controllers only know that their radar is hitting something there. Based on the speed and location, they can sometimes deduce that the target is a train, ship, or flock of birds, and they can be pretty confident that a blip going the speed of an airliner, in the location where an airliner transponder just stopped transmitting, is that airliner. Primary and secondary surveillance radars may have different coverage, so an airplane that could normally be tracked by its transponder signal may not be visible as a primary target.
- 2:15 a.m Malaysian military radar detects an unknown aircraft, possibly MH370, on a track that suggests it made another turn.
- 2:30 am Another possible military radar contact with the missing jet. I'm not sure if it shows the jet on the same track or not.
- 8:11 a.m. Final SATCOM ping received from the aircraft.
The aircraft had about eight hours of fuel on board at the speed it was going, and more if they reduced the power settings. I don't know the radar structure of the airspace they were in to say where they could get to without the aircraft being detected by an agency that would recognize and report its significance.
I don't know what it all means. I have a friend who is livid at the apparent lack of cooperation among the various military agencies who almost certainly have more information on the track of the missing airplane, but don't want to divulge their capabilities to one another. He also suggests that if the SATCOM signals were received by multiple satellites their source location could be triangulated. He also implied that a team of children with expertise at Where's Waldo should be put on the case, but I think the former suggestion was the more serious one.
Here is a link that answers some basic questions I didn't think people would ask, but people have some odd questions about airplanes. Someone asked me if this could be a case of pilot incapacitation, with the autopilot or random chance making those turns. I'd say no. The autopilot wouldn't be programmed to make those turns, and if the autopilot wasn't on, I would expect significant altitude changes. It's an odd incapacitation that would cause you to turn off two separate systems, one fourteen minutes before a normal call to ATC.
This one gives a pretty good explanation of tracking technology, and addresses the question of "how can we apply technology so this can't happen, and why haven't we done so already?"
Because I don't like to think of airplanes crashing if it's not necessary, I imagine that the pilots have stolen the aircraft, kidnapping the passengers. Although probably worse. It sounds like some cellphones were still switched on and even logged into social media accounts. Given the attachment some people have for their phones, it seems unlikely that that many people could be taken alive without anyone managing to get a message of some sort away. Despite my recent rewatching of the television Series LOST, I don't believe that the airplane has been spirited away to a mysterious island guarded by a smoke monster.
The facts that there will be wreckage if an airplane crashes, and that they haven't found wreckage, don't mean that the airplane didn't crash. It's a really BIG ocean, and it takes a long time to search. I liked this picture of Malaysian SAR crews. Of course it's probably posed, but I'm always attracted to shots that depict a group of people engrossed in something, not looking at the camera. It suggests expertise, focus, teamwork, and an important task. I also like the simplicity of the way the women's hijabs work with their flight suits.
I'll give the final word to The Onion, a satirical publication that doesn't know the phrase "too soon."
Update: They've pulled some location information out of the satellite data, but don't have enough satellites receiving the signal to resolve the position ambiguity.