Incident
On an unspecified date at 0844 Newfoundland standard time, a Beech 1900D aircraft, registration C-GLHO, serial number UE-266, operating as Lab Air 8333, was taxiing on Runway 02/20 at St. John's Airport when it struck a two-foot-high windrow that lay across the runway just north of taxiway Charlie. The aircraft sustained substantial damage. There were no injuries to the 10 passengers and two crew members.
Airport and Snow Removal Operations
St. John's Airport is a certified, controlled airport with three runways: 11/29, 16/34, and 20/02, all used year-round. Snow removal and winter runway maintenance priorities are established in the St. John's Airport Winter Maintenance Plan. Due to its Category II instrument approach capability, snow clearing efforts initially focus on Runway 11 and associated surfaces, unless wind conditions clearly favor Runway 16/34. Airport surfaces are designated under three priorities for snow clearing. Priority 3 surfaces are cleared last. Runway 02, north of taxiway Charlie to the entrance of taxiway Bravo, is designated as a priority 3 surface when either Runway 11/29 or 16/34 is active.
Several factors prevented the windrow from being reported. Neither the lead-hand nor the ground controller were made aware of its creation because windrows on non-active runways were not reported. The windrow's location was not used by ground vehicles or aircraft until Runway 29 became active, and it was outside the areas inspected by the night lead-hand during his shift. The night shift had an increased workload due to freezing drizzle, a stranded Airbus, and frequent runway changes, likely diverting attention from ensuring the taxi route north of Charlie intersection was usable. The shift change for snow removal crews coincided with the towing of the Airbus, the runway change, and the issuance of taxi clearance to Lab Air 8333. The windrow resulted from snow plowing activities; it is likely that whoever had knowledge of it had departed the field before the taxi clearance was issued. The oncoming lead-hand did not perform the customary field survey because of the pressing need to prepare Runway 29 and move the stranded Airbus. A field inspection would have allowed detection and removal or communication of the windrow.
Runway 02 north of Charlie was a low-priority surface, not used before Lab Air 8333 by vehicles or aircraft. It had not been cleared, was not usable, and was not necessary, yet it remained open. The St. John's Airport winter maintenance plan does not contain guidance for closing and reopening non-essential surfaces.
Crew Actions and Conditions
The crew's previous safe transit through the intersection and lack of warning of obstructions led them to proceed without extra vigilance. Flat-light conditions and the white background of uncleared airfield areas made the windrow blend into the background, less conspicuous from a distance. Approaching the intersection, the crew's attention was diverted by snow removal vehicles on Runway 16/34 approaching their location. During the subsequent taxi check, the first officer was reading the checklist and the captain was verifying flight instruments, preventing earlier detection.
The taxi speed and icy runway conditions hindered stopping, preventing the captain from applying reverse thrust or initiating the "Propeller Collisions during Ground Operation" checklist. Lower taxi speed would have provided more time to recognize and react.
Findings
The Transportation Safety Board completed an investigation, including FDR and CVR analysis (report LP001/03). Findings as to causes and contributing factors include:
- The aircraft was damaged when it collided with a windrow lying across its taxi path.
- Runway 02 north of Charlie taxiway was left open throughout snow removal even though not usable or required.
- Taxi speed did not allow sufficient time to respond once the windrow was seen, increasing risk.
- Lighting conditions made the windrow difficult to see.
- The windrow had not been reported to the night lead-hand, ground controller, oncoming lead-hand, or crew.
- A stranded Airbus, high maintenance workload, and shift change circumvented normal reporting procedures.
The St. John's Airport Winter Maintenance Plan does not require reporting windrows on non-active runways or contain instructions for closure and reopening of low-priority surfaces. The Airport Authority has issued a memorandum allowing the lead hand to close Runway 02/20 when conditions require.