This past weekend, one of the largest mass-delays of flights not due to weather affected more than 6,000 interisland passengers, and tens of thousands of travelers nationwide. Always Investigating sought answers about what happened.
Locally, Hawaiian Airlines was affected by a glitch that appears to be from a GPS software update. The Federal Aviation Administration, Hawaiian Airlines and other airlines nationwide still don’t have answers from the manufacturer about why it happened. No passengers were in any danger.
Hawaiian Airlines says this weekend was the most widespread delay and cancellation episode not caused by weather that they can recall at the usually punctual airline. Always Investigating asked more about what happened.
“It started with an enunciation that the GPS receiver is not receiving a GPS signal,” explained Capt. Ken Rewick, vice president of flight operations for Hawaiian Airlines.
“That alone would not ground the aircraft. The problem then was the transponder announced it wasn’t functioning correctly. That’s what grounded the aircraft.“
The transponder is what tells air traffic control where each plane is, and this glitch hit 14 interisland Hawaiian Airlines planes, plus many other airlines around the world, at midnight Greenwich Mean Time, or 2 p.m. Hawaiian time Saturday.
KHON2 asked, was there any warning it was coming?
“No, there was no warning,” Rewick said. “And it came as a surprise throughout the industry.“
A surprise especially since adding GPS data for transponders by 2020 is an FAA mandate, and conversions have been working fine for several months. Not so long ago, planes flew and air traffic control tracked them just fine without it.
KHON2 asked, was anyone ever in any danger, or were the pilots disabled in any way?
“No, not at all,” Rewick said. “The navigation of the aircraft was never compromised. We knew precisely where the aircraft were. The pilots operating the aircraft knew exactly where they were. The issue was that the air traffic and their system of radar coverage was not seeing the aircraft.“
Airlines across North America and Europe were hit. Locally only 14 out of 20 Hawaiian Airlines 717 interisland planes were affected. Hawaiian Airlines found a workaround by getting all 14 planes back to Honolulu to swap the malfunctioning GPS avionics with the original system. The FAA had them come in one by one.
“They (the FAA) only wanted one of those aircraft without a transponder at a time in the airspace,” Rewick explained. “So that’s what caused the delay.“
The delay pushed back 54 flights for more than 6,000 customers, ranging from 21 minutes to 5.5 hours. The glitch directly canceled 8 flight, plus 8 more that Hawaiian got up and running but too late for Lihue air-traffic control to accommodate. The latest restoration was a Maui flight at 1 a.m. Sunday. About 400 flights had to be canceled on Sunday on regional mainland carriers that use the same manufacturer’s GPS. Besides the 14 planes stalled by the glitch here in the islands, Hawaiian says the rest of its fleet was unaffected.
The FAA is investigating the incident nationwide and told KHON2 in a statement: “We are working to determine the cause of the problem, which may have resulted from a software update to the aircraft navigation systems.“
The FAA added that it “tracks flights on radar in addition to using satellite technology so airborne aircraft are under continuous surveillance by air traffic control.“
GPS system manufacturer Rockwell Collins did not yet respond to our questions about the cause. Hawaiian Airlines is waiting for an answer, too.
“There was evidentially a glitch of some sort in the upgraded avionics box that looks at the GPS and that was something that the manufacturer is trying to decipher now,” Rewick said.
KHON2 asked Hawaiian what they expecting of this vendor going forward?
“Transparency as to what the issue was, and a clear path forward to correct it and ensure it can’t happen again in the future,” Rewick said.
Airlines will have to continue conversions to include the GPS data for its transponders by the 2020 deadline.
“It will help in terms of efficient use of the airspace. It will mean that aircraft will burn less fuel, it will be very helpful,” Rewick said. “But clearly there was an issue here that nobody including the manufacturer nor the FAA had foreseen.“