What happened
The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.
On January 15 2018, Alaska flight 33, a B737-990ER, scheduled to fly from Boston logan international airport (bos) to portland international airport (pdx) collided with a deice truck operated by swissport ground handling. The collision occurred in the "juliet" deice pad at Boston airport.
Flight 33 was instructed by ground control to taxi to the juliet deice pad via taxiways bravo and juliet to the approach end of runway 14. As flight 33 approached the intersection of taxiways j and J-1, ground control reiterated their clearance for AS33 to proceed on juliet to the approach of runway 14, as a united 737 in the deice pad was facing taxiway juliet, and waiting for AS33 to pass before they could taxi out. When flight 33 approached the united aircraft, the captain offset his taxi about 6 feet to the right of centerline to ensure clearance from united's nose. After passing, the captain returned to centerline. An unattended swissport deice truck was parked in the j pad area, which is also a part of taxiway juliet. After passing the truck, the pilots reported feeling a small jolt. During this time, the first officer was repeatedly trying to contact the iceman on the published company frequency, but never received a reply. While flight 33 was holding short of closed runway 14 and waiting to deice, a deice employee noticed the collision and stopped the aircraft using signal wands. Also at this time, a flight attendant called to inform the pilots a piece had fallen off the aircraft's left wing. They received ATC clearance to return to the gate.
Causal factors include,
The investigation showed swissport had parked an unattended deice truck too close to taxiway juliet. Taxiway way juliet is approximately 60 feet wide and the wingspan of N263AK is 113 feet, with an approximate 26 foot overhang from the taxiway edgelines.
The deice truck was parked in an area that would normally be protected during deice ops.
As the FAA filed it
ON JANUARY 15 2018, ALASKA FLIGHT 33, A B737-990ER, SCHEDULED TO FLY FROM BOSTON LOGAN INTERNATIONAL AIRPORT (BOS) TO PORTLAND INTERNATIONAL AIRPORT (PDX) COLLIDED WITH A DEICE TRUCK OPERATED BY SWISSPORT GROUND HANDLING. THE COLLISION OCCURRED IN THE "JULIET" DEICE PAD AT BOSTON AIRPORT.
FLIGHT 33 WAS INSTRUCTED BY GROUND CONTROL TO TAXI TO THE JULIET DEICE PAD VIA TAXIWAYS BRAVO AND JULIET TO THE APPROACH END OF RUNWAY 14. AS FLIGHT 33 APPROACHED THE INTERSECTION OF TAXIWAYS J AND J-1, GROUND CONTROL REITERATED THEIR CLEARANCE FOR AS33 TO PROCEED ON JULIET TO THE APPROACH OF RUNWAY 14, AS A UNITED 737 IN THE DEICE PAD WAS FACING TAXIWAY JULIET, AND WAITING FOR AS33 TO PASS BEFORE THEY COULD TAXI OUT. WHEN FLIGHT 33 APPROACHED THE UNITED AIRCRAFT, THE CAPTAIN OFFSET HIS TAXI ABOUT 6 FEET TO THE RIGHT OF CENTERLINE TO ENSURE CLEARANCE FROM UNITED'S NOSE. AFTER PASSING, THE CAPTAIN RETURNED TO CENTERLINE. AN UNATTENDED SWISSPORT DEICE TRUCK WAS PARKED IN THE J PAD AREA, WHICH IS ALSO A PART OF TAXIWAY JULIET. AFTER PASSING THE TRUCK, THE PILOTS REPORTED FEELING A SMALL JOLT. DURING THIS TIME, THE FIRST OFFICER WAS REPEATEDLY TRYING TO CONTACT THE ICEMAN ON THE PUBLISHED COMPANY FREQUENCY, BUT NEVER RECEIVED A REPLY. WHILE FLIGHT 33 WAS HOLDING SHORT OF CLOSED RUNWAY 14 AND WAITING TO DEICE, A DEICE EMPLOYEE NOTICED THE COLLISION AND STOPPED THE AIRCRAFT USING SIGNAL WANDS. ALSO AT THIS TIME, A FLIGHT ATTENDANT CALLED TO INFORM THE PILOTS A PIECE HAD FALLEN OFF THE AIRCRAFT'S LEFT WING. THEY RECEIVED ATC CLEARANCE TO RETURN TO THE GATE.
CAUSAL FACTORS INCLUDE,
THE INVESTIGATION SHOWED SWISSPORT HAD PARKED AN UNATTENDED DEICE TRUCK TOO CLOSE TO TAXIWAY JULIET. TAXIWAY WAY JULIET IS APPROXIMATELY 60 FEET WIDE AND THE WINGSPAN OF N263AK IS 113 FEET, WITH AN APPROXIMATE 26 FOOT OVERHANG FROM THE TAXIWAY EDGELINES.
THE DEICE TRUCK WAS PARKED IN AN AREA THAT WOULD NORMALLY BE PROTECTED DURING DEICE OPS.