Would the waypoint SCCI (Punta Arenas) even be in the plane’s navigation system?

Good question.

The Flight MH370 Boeing 777-200ER was originally delivered to Malaysia Airlines on May 31, 2002.  It was the 404th 777 built.  It most likely came installed with a first generation AIMS-1 Airplane Information Management System.   Second generation AIMS-2 did not arrive until 2003.  Although the B777 can be upgraded, there is no public record of this and the Malaysian Factual Information Report simply refers to the system as “AIMS,” which can be taken as a generic name for AIMS-1/2 or what AIMS-1 was referred to as before AIMS-2 came along.

This is important, because the AIMS-1 avionics system has very limited memory (PDF document from MITRE Corporation) for navigation and airport databases.  In fact, with databases continually growing, it not possible for an AIMS-1 system to hold the entire world catalog.   Databases are provided by suppliers (Boeing’s Jeppesen, Lufthansa’s LIDO, or Navtech/ EAG) in ARINC 424 format.   It is not clear which supplier Malaysian Airlines used for their 777s, but Lufthansa’s LIDO system was selected for Malaysian Boeing 737s and Airbus A380s.  Airlines practice database capacity management by restricting what is loaded to grid squares or use other techniques such as restricting airports, which consume a lot of space.  Another strategy could be to restrict airports by runway length.  World databases for runways of 5000 feet or more are around 8MB in size, whereas the AIMS-1 stores 2 MB, but by restricting to only 777-capable runways, the size would be less. It’s not clear if restricting to longer 777-capable runways, the world would fit in AIMS-1.  Airlines actually have limited capability to modify these databases, but would coordinate with the vendor.  GIven the popularity of the 777 as a “worldliner,” they have no doubt come up with solutions.

Accuracy is very important and navigation databases are generally regulated to be refreshed every 28 days, so every 28 days, 9M-MRO (MH370) should have received an upload of the latest database on a floppy disc (yes, typically a 3.5-inch floppy disc unless they had AIMS-2 and something better like Alaska Airlines).  The pilot and copilot can display the current database version and expiry dates on their respective displays (Control Display Unit or CDU).  According to Boeing, the diskettes are intended to be kept in a binder on the airplane. The uploads would have been done with something like a Maintenance Access Terminal (MAT) or Teledyne Controls Portable Maintenance Access Terminal (PMAT) (PDF).  PMATS can be kept in the aircraft’s E/E Bay (Main Equipment Center (MEC)), but there is a MAT terminal and PMAT port on the flight deck, and PMAT ports in the nose and right wheel wells and the Jack Screw area.  Here is an incredible video tour of a 777 E/E bay in-flight, with a shot of a PMAT device and the AIMS system (courtesy LGHamiltonUSA).

Newer versions of dataloaders are wireless, for example Teledyne’s eADL Wireless Ground Link.  These airborne data loaders can save airlines money, not to mention the hassle of floppy discs.  Such system are available for 777s but It is not clear what kind of system Malaysian Airlines would have used.

Malaysian Airlines flew to Buenos Aires, Argentina as recently as 2012, so it’s conceivable they would have had ARINC 424 format South American region navigation data on hand, at least in old versions.   These filghts were by Boeing 747s, however, likely due to ETOPs restrictions (twin engine planes are limited to how long they can fly on one engine in case of engine failure) on 777s that only recently were revised.  Punta Arenas’ Carlos Ibanez del Campo International has a runway capable of landing a 777 and would easily be in such a regional database as an alternate airport, I would guess.  If not, it could simply be there as a waypoint.

ATSB, in their June Underwater search areas report examined the possibility that MH370 flew through the waypoint RUNUT as discussed in The Destination.  This could perhaps be included in a southeast asia regional database, but it’s not clear whether ATSB was guessing or actually knew what was installed on MH370.

It is unknown what Malaysian Airlines may have subscribed to for their regular navigation database (NDB) subscriptions, or what regions they specified to be installed on their 777s.  Different planes could easily have different regions installed.   9M-MRO flew all over the world in it’s history, so it’s unclear how MAS would have managed the limited AIMS-1 memory for this plane.

All that to say: I don’t know, but it’s unlikely if the aircraft was using AIMS-1, depending on Malaysian Airlines navigation database policies.  Unless someone intentionally installed it there, however, the path coincidentally fits.

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One thought on “Would the waypoint SCCI (Punta Arenas) even be in the plane’s navigation system?

  1. Pingback: The brains of a Boeing 777, simple and complex | The Waypoint Hypothesis

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