Boeing 787 "Blacklisted" From Some Air Traffic Control Services (flightglobal.com)

An anonymous reader writes: A software glitch causes the Boeing 787 to report its position incorrectly, which has led Australia and Canada to 'blacklist' the aircraft from using ADB-S and until it is resolved the latest Boeing is treated as an aircraft without ADS-B capabilities. The practical implication is that the aircraft is not allowed to use reduced separation procedures and an maximum altitude limit of 29,000 feet was also considered. Boeing denies that the bug causes a safety hazard because existing services (radar) still allow safe operation. A bugfix is coming to restore ADS-B functionality.

Comments

Re:It's not really a blacklist then, is it?

[Anonymous Coward]

It's graceful degradation.

No, a graceful degradation would be the plane recognizing it's not operating correctly and falling back to the older service. This is a case where the plan is actually trying to use the newer/better service, failing to do so correctly, and it not aware that it is failing to do so. The humans involved are noticing the error and have had the blacklist the plan from the newer system and manually force a fallback to the old system.

I mean seriously, the second sentence in TFA even says:
Boeing says a service bulletin with instructions for operators to correct the position reporting error will be released “imminently"

Re:So the plane tells ATC where it is...

[brambus]

I know you were trying to be snarky, but you did accidentally ask a good question where the answer isn't trivial:

• Since the dawn of radar ATC, civilian radar has been SSR - Secondary Surveillance Radar, meaning, it requires cooperation from the aircraft. SSR gives you the horizontal location of the target, but not its elevation. Instead, together with the actual radar return, the aircraft responds using a short digital code that identifies it and tells you its altitude (as read from the onboard altimeter by the SSR equipment on the aircraft). SSR has numerous advantages over PSR, mainly its not as complex, doesn't require as much power and has greater range, all of which are useful in a civilian environment. Also, it has no military application, so it carries far fewer export concerns.
• Even so, SSR is still very expensive and providing good coverage is difficult to impossible. Even modern industrialized countries such as the USA have many places where radar coverage is simply unavailable (especially at lower altitudes). In less well of places, such as large areas of Africa, radar coverage is nonexistent.
• The vast majority of all aircraft (and nearly all commercial aircraft) have some sort of navigational equipment that is completely independent of radar coverage and is reasonably accurate to provide traffic separation services. Put simply, aircraft are able to navigate without any ground assistance.

And so the natural evolution is to largely abandon SSR (except for areas of extremely high traffic density) and instead place around the country only small receiver stations that listen to aircraft position reports. Using those then, ATC can build a complete traffic picture and provide separation services without having to maintain expensive ground equipment.

Re:at least is not tcas off

[DesertNomad]

I run a number of ADS-B receivers and feed the data into FlightAware. I have seen a number of a/c locally that are in very wrong positions (well over the 70 km mentioned in TFA) and suddenly jump into the "right" positions. Sounds like interface problems.

The ADS-B system is fairly simple, and as long as the right lat-lon string is inputted, it should transmit the right position. Maybe it's a "units" issue similar to the "units" issue that caused the Mars spacecrafts more than a decade ago to make an unexpected and unfortunate (very) hard landing...

Re:at least is not tcas off

[parkinglot777]

Here is the cause on the TFA (which is what Boeing said)...

In rare cases, after passing a planned turn upon crossing a waypoint, the data packets that arrived at the transponder would contain either the aircraft’s latitude or longitude, but not both. In those cases, the ADS-B transponder’s software would extrapolate the 787’s position based on the previous flight track before it made a planned turn at a waypoint. It would continue reporting the aircraft erroneously on the incorrect track until it received a data packet containing both the latitude and the longitude of the aircraft.