Malaysia Flight #370: Charts, the Filed Flightplan, and a few Notes

The news coverage of the disappearance of Malaysia Flight #370 seems to be lacking critical details about the ATC airspace and the filed flightplan. Most of these details are available online, but some are difficult to locate, and nobody has yet compiled them. So, to help us all start to understand what may have happened, here are some navigation charts and here is the filed flightplan route for MAS370 (from Flightaware.com):

DCT PIBOS R208 IKUKO M076F290 R208 IGARI M765 BITOD N0480F330 L637 TSN N0490F350 W1 BMT W12 PCA G221 BUNTA N0480F350 A1 IKELA N0480F350 P901 IDOSI N0480F390 DCT CH DCT BEKOL K0890S1160 A461 YIN K0890S1190 A461

Translated, the planned route/attitude was as follows:

  • takeoff from Kuala Lumpur, expecting radar vectors to PIBOS intersection, where route R208 would be joined.
  • proceed via route R208 to IKUKO intersection (at the boundary between airspace controlled by Malaysia vs. controlled by Singapore).
  • continue on route R208 (at speeds Mach .78 and altitude 29,000′ MSL) to IGARI intersection. The chart shows this distance is 74 nautical miles. See the enlarged chart further down in this Post; note that IGARI intersection is just prior to the boundary with Vietnam controlled airspace.
  • make a slight right turn and proceed via route M765 to BITOD intersection. The chart shows this distance is 37 nautical miles.
  • make a slight left turn and proceed via route L637 to [TSN], the Tan Son Nhut fix/navaid, essentially at Ho Chi Minh City. The flightplan indicates intention to climb to altitude 33,000′ MSL.
  • make a slight right turn and proceed via route W1 to [BMT], the Buonmathuot fix/navaid. The chart shows this to be a distance of 150 nautical miles. The flightplan indicates intention to climb to altitude 35,000′ MSL.
  • make a slight right turn and proceed via route W12 to [PCA], the Phucat fix/navaid.
  • make a slight left turn and proceed via route G221 to BUNTA intersection. The chart indicates distance is 173 nautical miles.
  • make a slight right turn and proceed via route A1 to IKELA intersection. The chart indicates distance is 197 nautical miles. IKELA is a boundary fix, at the start of airspace controlled by Hong Kong.
  • …and from there, proceed through Chinese airspace to land at Beijing. The flightplan indicates the final altitude (attained after burning off some fuel weight) was to be altitude 39,000′ MSL.

The Disappearance:

The latest news reports (eight days after the incident) included this:

“…Based on new satellite communication, we can say with a high degree of certainty that the aircraft communications addressing and reporting system (ACARS) was disabled just before the aircraft reached the east coast of Peninsular Malaysia. Shortly afterwards, near the border between Malaysia and Vietnamese air traffic control, the aircraft’s transponder was switched off. From this point onwards, the Royal Malaysian Air Force primary radar data showed that an aircraft which was believed but not confirmed to be MH370 did indeed turn back. It then flew into a westerly direction back over Peninsular Malaysia before turning northwest. Up until the point at which it left military primary radar coverage, these movements are consistent with deliberate action by someone on the plane….”

“…Today, based on raw satellite data which was obtained from the satellite data service provider we can confirm that the aircraft shown in the primary radar data was flight MH370. After much forensic work and deliberation, the FAA, NTSB, AAIB and the Malaysian authorities working separately on the same data … according to the new data the last confirmed communication between the plane and the satellite was at 8:11am Malaysian time Saturday 8 March. The investigation team is making further calculations which will indicate how far the aircraft may have flown after the last point of contact. This will help us to refine the search….”

These reports (from an excellent blog Post at Leehamnet.com) indicate that the actions were taken by an individual(s) with substantial knowledge of airspace control boundaries, Boeing 777 system control switches, etc. Also, that the key actions taken were to cut off satellite communications just prior to crossing the northeast Malaysian coastline, and then cut off radar transponder communications in the vicinity of IGARI intersection.

Here’s a blow-up of the high-altitude air navigation chart (from http://skyvector.com/), marked up with key flightplan fixes. Note that the distance between Malaysia’s northeast coast and the southern area of Vietnam is roughly 200 miles, making the critical area where the flight ‘disappeared’ roughly one hundred miles offshore (and midway across the Gulf of Thailand) — right near the limits of available ATC radar coverage. Certainly, a seasoned pilot would know the limits of radar coverage and be able to time his/her actions to avoid raising immediate suspicion.

Lastly, a NYTimes article had this:

“…Radar signals recorded by the Malaysian military appeared to show that the missing airliner climbed to 45,000 feet, above the approved altitude limit for a Boeing 777-200, soon after it disappeared from civilian radar and turned sharply to the west, according to a preliminary assessment by a person familiar with the data….”

Wikipedia lists the service ceiling at 43,100 feet. So, if the 45,000 foot altitude information is correct, the pilot was pressing the envelope to go as high as possible, likely with the intent of causing oxygen starvation within the cabin area.