JS31, Fort St. John BC Canada, 2007
JS31, Fort St. John BC Canada, 2007
On 9 January 2007, a Peace Air British Aerospace Jetstream 31 on a scheduled service flight from Grand Prairie, Alberta made an instrument approach to Runway 29 at Fort St. John, British Columbia and touched down 320 feet short of the runway striking approach and runway threshold lights.
Description
On 9 January 2007, a Peace Air British Aerospace Jetstream 31 on a scheduled service flight from Grand Prairie, Alberta made an instrument approach to Runway 29 at Fort St. John, British Columbia and touched down 320 feet short of the runway striking approach and runway threshold lights. The right main and nose landing gear collapsed and the aircraft came to rest on the right side of the runway, 380 ft from the threshold.
There were no injuries to the 2 pilots and 10 passengers. At the time of the occurrence, runway visual range was fluctuating between 1800 and 2800 ft in snow and blowing snow, with winds gusting to 40 kts.
The Investigation
An Investigation was carried out by the Canadian Transportation Safety Board. The very low levels of actual Instrument Flight Rules (IFR) flight experience of both flight crew were considered to have played a major part in the occurrence.
Their findings as to Causes and Contributing Factors were as follows:
- A late full flap selection at 300 ft above ground level (agl) likely destabilized the aircraft’s pitch attitude, descent rate and speed in the critical final stage of the precision approach, resulting in an increased descent rate before reaching the runway threshold.
- After the approach lights were sighted at low altitude, both pilots discontinued monitoring of instruments including the glide slope indicator. A significant deviation below the optimum glide slope in low visibility went unnoticed by the crew until the aircraft descended into the approach lights.
Their findings as to Risk were as follows:
- The crew rounded the decision height (DH) figure for the instrument landing system (ILS) approach downward, and did not apply a cold temperature correction factor. The combined error could have resulted in a descent of 74 ft below the DH on an ILS approach to minimums, with a risk of undershoot.
- One other Finding of the Investigation was given. This was that as “the cockpit voice recorder (CVR) was returned to service following an intelligibility test that indicated that the first officer’s hot boom microphone intercom channel did not record. Although the First Officer voice was recorded by other means, a potential existed for a loss of information, which was key to the investigation.
Related Articles
Further Reading
- The TSB Report was published on 2 October 2007.