These are only a selection, and have been taken directly from the TAIC report.
See here for the full TAIC report.
- Icing conditions were forecast, and optimum icing conditions existed along the route at the altitudes planned and flown by the pilot.
- The pilot was probably unaware of any forecast or reported icing conditions along the planned route.
- The pilot may not have been aware of ice forming on his aircraft.
- Ice probably formed rapidly to a critical level on the aircraft, causing it to stall and enter a spiral dive.
- A defect in the combustion heater was likely to have led to an unacceptable level of carbon monoxide in the aircraft cabin.
- A progressively increasing level of carbon monoxide probably caused significant pilot mental confusion and impairment, and may have led to a subsequent loss of situational awareness.
- The pilot was unlikely to have been rendered unconscious or suffered total incapacitation by the carbon monoxide contamination during the early stages of its onset.
- Spatial disorientation, likely during the descent, would have reduced the pilot's chance of successfully regaining control of the aircraft in the short time available.
- A coherent safety culture did not exist within United Aviation.
- No effective means were used to ensure pilots understood or complied with documented United Aviation operating procedures.
- United Aviation’s safety-related procedures and supervisory practices were inadequate.
- United Aviation's competency checking and training of its pilot was inadequate.
- United Aviation did not ensure the pilot had access to necessary meteorological information.
- United Aviation did not actively discourage the use of invalid and inappropriate meteorological information.
- United Aviation had not analysed the particular risks associated with the accident flight, or put in place suitable defences to counter the risks.
- United Aviation did not ensure that its pilots had sufficient knowledge of the dangers associated with in-flight icing conditions to plan their flights to avoid these hazards.
- As United Aviation was responsible for compliance with CAA legislation and the safe operation of its aircraft, it was incumbent on it to respond in a timely and appropriate manner to CAA audit findings to ensure the safe operation of its aircraft.
- United Aviation did not respond in a timely and appropriate manner to CAA audit findings.
- The CAA auditing process detected some uncorrected deficiencies in the United Aviation operating and maintenance procedures over a period of at least three years before the accident.
- Safety concerns raised in CAA audits of United Aviation did not result in an appropriate response such as the imposition of sanctions by CAA to ensure United Aviation rectified its non-compliances and non-conformances.
- Given the number of new and repeat non-compliances and non-conformances detected during each audit, the CAA should have taken firmer action, if necessary suspending United Aviation's Air Service Certificate, well before it did.
- No safety recommendations could be made to United Aviation, as a result of the Director of Civil Aviation revoking United Aviation's operating certificates, and United Aviation entering receivership.
- As a result of recognising deficiencies within its audit process, including audit findings not being followed up effectively, the CAA began restructuring its auditing operations from November 1996. The CAA advised it has put in place procedures intended to follow up on audit findings effectively. These procedures require individual auditors to ensure operators carry out any corrective action necessary to rectify deficiencies and shortcomings identified during CAA surveillance. If an auditor discovers that corrective action has not been carried out by the due date the auditor will send a reminder notice to the operator. The auditor will send a second notice if corrective action is still not carried out. If a third notice is necessary the Controller Safety Audit will issue the notice and advise the operator that unless corrective action is carried out a recommendation will be made calling for a suspension of the operating certificates.