Executive/Corporate/Business

It was determined that the aircraft impacted ground after the pilot continued the approach in below minima weather conditions.
The following findings were identified:
- The pilot continued the descent below MDA until the aircraft impacted ground,
- Few seconds prior to the accident, ATC instructed twice the pilot to initiate a go-around procedure, but this was too late,
- The pilot was approaching the airport at an excessive speed and below the glide,
- Poor visibility due to low clouds (below minimums).

Findings as to Causes and Contributing Factors:
1. Suspended water in the fuel system precipitated out of solution and froze in the fuel distributor valve. This blocked the fuel supply to the fuel nozzles and led to the loss of engine power.
2. The aircraft was being operated without a fuel additive icing inhibiter. Use of such an additive would have inhibited ice formation in the aircraft’s fuel system and would likely have prevented the fuel system blockage.
Findings as to Risk:
1. The fuel distributor valve on the Aero Commander 500B is exposed directly to the cooling blast of the outside air, which under extremely cold conditions, can lead to the freezing of super-cooled water droplets present in the fuel stream.
2. The operator did not have procedures to describe how fuel additive icing inhibiter should be used during winter operations.

Findings as to Risk:
1. Because aircraft EWH information is not readily available to pilots, crews may continue to conduct approaches with an aircraft mismatched to the visual glide slope indicator (VGSI) system, increasing the risk of a reduced TCH safety margin.
2. Due to limited knowledge of the various VGSI systems in operation and their limitations, flight crews will continue to follow visual guidance that might not provide for safe TCH.
3. Jetport did not develop an accurate company risk profile. This precluded identification of systemic safety deficiencies and development of appropriate mitigation strategies.
4. If adequate safety oversight of POC operators is not maintained by the regulator, or the delegated organization, especially during SMS implementation, there is an increased risk that safety deficiencies will not be identified.
5. The fact that the Canadian Business Aviation Association (CBAA) did not insist that milestones for SMS implementation and development be followed may result in some POC operators never reaching full SMS compliance.
6. If Transport Canada does not ensure that the CBAA fulfills its responsibilities for adequate oversight of the Canadian Aviation Regulations (CARs) subpart 604 community, safety deficiencies will not be identified and addressed.
7. The audit of Jetport’s SMS, conducted by the CBAA–accredited auditor, did not identify the deficiencies in the program or make any suggestions for improvement. Without a comprehensive audit of an operator’s SMS, deficiencies could exist resulting in the operator’s inability to implement an effective mitigation strategy.
8. Contrary to the recommendations made in the Transport Canada/CBAA feasibility studies, the CBAA did not have a quality assurance program for its audit process. As a result, there is a risk that the CBAA will fail to identify weaknesses in the POC audit program.
9. At the time of the accident, no one at Fox Harbour (CFH4) had been assigned responsibility for regular maintenance of the APAPI, therefore preventing timely identification of APAPI equipment misalignment.
10. Jetport’s risk analysis before the introduction of the Global 5000 did not identify the incompatibility between the EWH of the aircraft and the APAPI at CFH4.
11. Not wearing shoulder harnesses during landings and take-offs increases the potential risk of passenger injuries.
12. Passengers not wearing footwear could impede evacuation, increase the risk of injury, and reduce post-crash mobility and (potentially) survival.
Other Findings:
1. A SMS integrates sound risk management policies, practices, and procedures into day-to-day operations and, properly implemented, offers great potential to reduce accidents.
2. Contrary to its own assessment protocol, Transport Canada did not document its decision to close off the CBAA assessment even though the CBAA had not submitted an acceptable corrective action plan.
3. Depiction of the different types of VGSIs differs, depending on the publication.

The pilot's failure to maintain a positive climb rate during an instrument takeoff. Contributing to the accident was the low visibility.

The pilot's intentional visual flight rules (VFR) flight into instrument meteorological conditions (IMC), and his failure to maintain clearance from the trees and terrain during climb. Contributing to the accident were the weather conditions of fog and a low ceiling, and the mountainous/hilly terrain.

The pilot's failure to maintain aircraft control during the landing.

Failure of both engines in flight due to fuel exhaustion. The following contributing factors were identified:
- Poor judgment on the part of the pilot who considered that the quantity of fuel present in the tanks before departure was sufficient, which was not the case,
- Poor flight planning on part of the pilot who miscalculated the fuel consumption,
- The pilot failed to follow the procedures related to fuel policy.

The pilot's failure to initiate a missed approach and his failure to obtain the proper touchdown point while landing in the rain. Contributing to the accident were the operator's lack of standard operating procedures and the inadequate maintenance of the windshield.

Engine power loss during initial climb after the aircraft had been refueled with Jet fuel instead of Avgas 100LL.
The following contributing factors were identified:
- The low experience of the pilot on type,
- The non-compliance of correct refueling procedure and its supervision by IOC personnel and pilot or operator's representative.

Structural failure and damage:
From the detailed examination and study of the aircraft wreckage undertaken by ATSB investigation staff, it was evident that all principal structural failures had occurred under gross overstress conditions i.e. stresses significantly in excess of the physical strength of the respective structures. The examination found no evidence of pre-existing cracking, damage or material degradation that could have appreciably reduced the strength of the failed sections, nor was there any indication that the original manufacture, maintenance or repair processes carried out on the aircraft were in any way contributory to the failures sustained.

Breakup sequence:
From the localised deformation associated with the spar failures, it was evident that the aircraft had sustained a large negative (downward) loading on the wing structure. That downward load resulted in the localised bending failure of the wing around the station 145 position (145” outboard of the aircraft centreline). The symmetry of both wing failures and the absence of axial twisting within the fuselage section suggested that the load encountered was sudden and well in excess of the ultimate strength of the wing structure. Based upon the witness marks on both wing under-surfaces and the crushing and paint transfer along the leading edges of the horizontal stabilisers, it was concluded that after separating from the inboard structure, both wings had moved aft in an axial twisting and rotating fashion; simultaneously impacting the leading edges of both horizontal tailplanes. Forces imparted into the empennage structure from that impact subsequently produced the rearward separation of the complete empennage from the fuselage. The loss of the left engine nacelle fairing was likely brought about through an impact with a section of wing leading edge as it rotated under and to the rear. The damage sustained by all of the aircraft‟s control surfaces was consistent with failure and separation from their respective primary structure under overstress conditions associated with the breakup of the aircraft. There was no evidence of cyclic or oscillatory movement of the surfaces before separation that might have suggested the contribution of an aerodynamic flutter effects.

Findings
The following statements are a summary of the verified findings made during the progress of the aircraft wreckage structural examination and analysis:
- All principal failures within the aircraft wings, tailplanes and empennage had occurred as a result of exposure to gross overstress conditions.
- The damage sustained by the aircraft wreckage was consistent with the aircraft having sustained multiple in-flight structural failures.
- The damage sustained by the aircraft wreckage was consistent with the structural failure sequence being initiated by the symmetric, downward bending failure of both wing sections, outboard of the engine nacelles.
- Breakup and separation of the empennage was consistent with having been initiated by impact of the separated outboard wings with the leading edges of the horizontal stabilisers.
- There was no evidence of material or manufacturing abnormalities within the aircraft structure that could be implicated in the failures and breakup sustained.
- There was no evidence of service-related degradation mechanisms (such as corrosion, fatigue cracking or environmental cracking) having affected the aircraft structure in the areas of failure.