Monday, January 26, 2015

High Time for Satellite Tracking of All International Flights

This coming March 8 will mark one year since Malaysia Airlines Flight 370 disappeared from radar en route from Kuala Lumpur to Beijing somewhere over the Indian Ocean.  The wreckage has never been found, although communications experts used some almost accidental satellite-transponder data to estimate the last known location of the plane.  At the time, I recall thinking that if I was an airline and owned a number of high-value mobile assets known as airliners, I would want some way of knowing where each one was every minute or so, anywhere in the world.   After all, the technology for tracking the much cheaper assets called semi-trailer trucks has been around for years.  The little white domes on truck cabs report minute-by-minute locations to a data center where operators can pay a monthly fee to any one of a number of firms to keep tabs on shipments, and truck drivers too, for that matter.  But there is no international requirement for airlines to do the same.

Last week, the U. S. National Transportation Safety Board (NTSB) waded in with a recommendation for all passenger airliners to be equipped with improved location technology.  The board admitted it was motivated partly by Flight 370's disappearance, and called both for improvements in in-flight tracking and in "black-box" technology. 

The in-flight tracking part seems to be pretty straightforward technologically.  It would operate more or less the same way as the truck-tracking system.  Every minute or so, a GPS receiver on the plane would send its location to a satellite in view, and the satellite would relay that information to a data center, where it would be logged and made available in the event of an incident of interest.  The only slightly tricky part would be identifying which satellite to use.  But there are already geostationary satellites in orbit such as Inmarsat which provide virtually world-wide coverage, and the missing bits of Earth near the poles could be made up for by linking to numerous low-earth-orbit satellites in polar orbits. 

The technology is not nearly so much a hurdle as the cost and the peculiar structure of international aviation regulations.  The NTSB's recommendations went to the U. S. Federal Aviation Administration, and if the FAA adopts them they will be obligatory for all U. S. airlines—but nobody else.  Because the U. S. operates only a fraction of international flights over large bodies of water where the technology would be most useful, the idea will not succeed without international cooperation, and that means the International Civil Aviation Organization, or ICAO.

The ICAO is a United Nations body in charge of international standards for, well, civil aviation, as you might expect.  As such, its rulings have no force of law in individual countries unless the countries' own aviation regulations require that its carriers follow ICAO rules as well, which most do.  It was a 2008 ICAO ruling, for example, that required all air traffic controllers and flight crew members involved in international flights to be proficient in English.  I'm rather surprised that it took until 2008, but after all, everything takes a while at the UN.

The question is whether and when the ICAO might follow the NTSB's lead if the NTSB prevails with the FAA to make international-flight GPS tracking mandatory.  Enough alphabet soup for you?  The whole process—from tragic accident to technical recommendations to changes in laws and regulations—is typical of how safety technology develops in coordination with regulations requiring its use.  And the regulatory part is particularly tricky when it involves spending money.  The requirement that pilots speak English can be met by changing hiring practices, but GPS tracking will involve both up-front and ongoing expenses for new hardware—which itself needs to be standardized somehow—and rental fees to the commercial firms that operate the satellite transponders used to convey the location data.  Fortunately, we are not talking about large bandwidths here—the equivalent of a single cellphone text message every minute or so would be sufficient.  But coordinating all this will take some doing, and coordination of any kind at the level of the ICAO is a challenging and slow-moving process at best.  If they took till only seven years ago to agree on a common language for radio communications from international flights, the ICAO isn't going to churn out new GPS-location rules overnight, you can be sure. 

The other part of the NTSB recommendations concerns the nature of the onboard flight data recorders.  Now that video cameras and recording equipment are so inexpensive, the NTSB says we should have cockpit video as well as audio recorders, and that controls for the entire system should be inaccessible from the cockpit.  (There is some suspicion that the radar-transponder system of Flight 370, which works only within range of ground-based tracking radars, was intentionally disabled by the pilot.)  Also, the NTSB floated the idea (so to speak) that the flight recorders should be housed in buoyant housings and ejected upon impact so that they can remain on the surface, where their radio signals could be more easily received than the limited-range and limited-time sonar emissions that the units currently send out underwater. 

All these are good ideas, and if the FAA adopts them they will make an already safe U. S. air-travel system even safer, or at least increase the likelihood of finding any flights that go down in deep water.  And the information from such accidents is always valuable in preventing the next one, whether it was caused by mechanical failure, human error, or evil intent.

Nevertheless, I am not going to be holding my breath until the ICAO follows suit.  You would think that the international carriers themselves would have adopted something similar to the truck-tracking systems years ago, but there may be a mentality in place that makes such a system seem unnecessary because of the vanishingly small number of incidents in which it would turn out to be useful.  But once GPS tracking for international flights is in place, I bet folks find other uses for it, for things like fuel-economy efforts and even weather tracking.  But first, the ICAO has to get in gear, so stay tuned.

Sources:  The article "NTSB:  Planes Should Have Technologies So They Can Be Found" by Joan Lowy of the Associate Press was carried by numerous outlets, including ABC News on Jan. 22 at  I also referred to Wikipedia articles on Malaysia Airlines Flight 370, Inmarsat, and the ICAO.

Addendum Feb. 1:  Edwin Doetzal wrote me on Jan. 31 as follows:

"Your analysis of MH370 contained a couple issues:
Airliners do often have SATCOM tracking 'like trucks'.  On MH370, this system was turned off along with the radio transponder.
ADS-B is the new satellite based air traffic control system that will replace the radio based air traffic control system and is already being implemented through efforts by NAVCanada and ICAO.
What is currently in discussion are new systems such as AFIRS that would stream amounts of data automatically or by trigger in an emergency as well as explosive jettisoned FDR/CVR units.  Knowing where an aircraft was is of course not enough without the detailed DAQ information that might explain why the emergency happened and what action was taken by the flight crew.  A truck's limited DAQ can be retrieved from the ditch.  Please be assured that an airliner is a much more sophisticated system than a truck.
It was somewhat troubling to see such an article on an 'engineering ethics' blog.  With respect, it would seem that you are speaking outside your professional scope.  A retraction would appear appropriate.

Edwin Doetzel

Lay Person"

It was careless of me to imply that airliners had no such tracking systems, and I apologize
for leaving that impression.  In the space I had, I meant to concentrate not so much on the technology as on the international coordination that would be needed to implement it uniformly so that flights such as MH370 would not slip through the cracks.  My thanks to Mr. Doetzel for the correction.  

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