Last Wednesday evening a Northwest Airbus 320 jet airliner from San Diego to Minneapolis (Flight NWA188) went for over an hour without talking to air traffic controllers (NORDO) and subsequently overflew its destination by 150 miles before its pilots became aware.
(This is the second big newsworthy incident for Northwest airlines: in 1990 a Northwest crew flew a B727 jet carrying 91 passengers from Fargo to Minneapolis while intoxicated.)
Initial reports said that the flight was out of radio contact for over 75 minutes, but the FAA letters revoking both pilots’ licenses said that they had been out of contact for 91 minutes.
For a few days immediately afterwards it was a mystery as to what the pilots were doing and many speculated that they had fallen asleep. But both the the pilot and co-pilot denied that from the very beginning instead claiming they had become distracted by a conversation.
In February of 2008 a Go! Airlines commuter flight flew past its destination when both the pilot and co-pilot flew asleep. It was later found that the pilot suffered from sleep apnea.
The ensuing investigation in the Northwest incident showed that the crew said they had been working on their laptop computers using a flight crew scheduling program. Now there isn’t an application in the world that has the potential to engage me to the point that I have no idea about what’s going on around me for over an hour, especially if I was supposed to be doing something else (like flying an airplane), so I’m still skeptical but that’s really beside the point now.
Not surprisingly both the airline and the pilots union are trying to downplay this incident, but it’s a pretty big deal for a reason none of the major news agencies have yet reported.
Airlines don’t tend to completely fill their aircraft with fuel. Fuel is weight, and carrying extra weight on an aircraft uses more fuel to operate. So the airlines usually load just enough fuel for the flight so they’re not carrying extra weight in the form of fuel. They’re also supposed to consider weather that might impact the flight.
The Federal Aviation Regulations (FAR) Part 121.639 dictates that at a bare minimum airlines have to load enough fuel on the aircraft to get to the destination, have enough to fly to their “most distant alternate airport” (if they can’t land at their intended destination), plus 45 minutes of extra fuel.
Considering the Northwest jet flew almost a half hour past its destination, by the time it landed it could have been fairly close to using the reserve 45 minutes of fuel (or worse been using that reserve fuel). Time will tell if we ever get to hear how much fuel was left on board the jet when it landed.
Since the flight crew missed various audio alerts/alarms, including the one from the flight computer (FMS) when it overflew its last programmed waypoint (Minneapolis), any warnings that it was running out of fuel would probably have been missed as well. On the Airbus 320 when the aircraft overflew its destination the FMS would have continued to fly on it’s last heading until it ran out of fuel.
But just as notable is that even though air traffic controllers hadn’t talked to the flight in over an hour and it overflew its destination, fighter jets never got airborne to intercept the wayward flight.
The Federal Aviation Administration violated its own rules by taking more than 40 minutes to alert the military after losing communication with a Northwest Airlines flight last week, according to officials familiar with internal reviews under way at several federal agencies.
The delay has sparked consternation within the military, concern within the FAA and special oversight by the White House, these officials said, particularly because such time lags were supposed to be eliminated as a result of the lessons learned from the Sept. 11, 2001, terrorist attacks. In the event of a hijacking, the military would order fighters into the air to intercept an aircraft and possibly shoot it down.
This incident is likely going to cost the pilots their jobs. The FAA certainly didn’t delay in revoking their pilots licenses.
But they’re not the only ones who didn’t do their jobs the way they were supposed to that day…