Casa 212 Aviocar

Factors:
1. The flight was in VFR however both pilots agreed to fly into the cloud, consequently, the flight crew had lack of situation awareness due to lost of visual references to the ground and no or late recovery action prior to impact due to low visibility.
2. There was lack of good crew coordination due to steep cockpit transition gradient.
3. There was no checklist reading and crew briefing.

The accident was caused by the loss of control of the airplane while performing the tailwind leg through the channel between the islands of Robinson Crusoe and Santa Clara to an estimated height of 650 feet or less, during the circuit approach to Runway 32 in a very low trajectory (with little height difference above the runway), where very adverse airflow conditions were found, including wind shear, which exposed the crew to extreme flight conditions.
Adverse airflow conditions were the results of a combination of different factors, including:
- Very unstable atmosphere, with strong turbulence and possibly eventually powerful down gusts arising from the presence of open cells after a front passed,
- The presence of the two counter-rotating vortexes in the Santa Clara Island downwind wake,
- The presence of strong and gusty crosswinds that were very variable in strength and direction in a very short time.

Conclusions
Findings as to Causes and Contributing Factors:
1. The right engine lost power when the intermediate spur gear on the torque sensor shaft failed. This resulted in loss of drive to the high-pressure engine-driven pump, fuel starvation, and immediate engine stoppage.
2. The ability of the left-hand No. 2 ejector pump to deliver fuel to the collector tank was compromised by foreign object debris (FOD) in the ejector pump nozzle.
3. When the fuel level in the left collector tank decreased, the left fuel level warning light likely illuminated but was not noticed by the crew.
4. The pilots did not execute the fuel level warning checklist because they did not perceive the illumination of the fuel level left tank warning light. Consequently, the fuel crossfeed valve remained closed and fuel from only the left wing was being supplied to the left engine.
5. The left engine flamed out as a result of depletion of the collector tank and fuel starvation, and the crew had to make a forced landing resulting in an impact with a concrete noise abatement wall.
Findings as to Risk:
1. Depending on the combination of fuel level and bank angle in single-engine uncoordinated flight, the ejector pump system may not have the delivery capacity, when the No. 1 ejector inlet is exposed, to prevent eventual depletion of the collector tank when the engine is operated at full power. Depletion of the collector tank will result in engine power loss.
2. The master caution annunciator does not flash; this leads to a risk that the the crew may not notice the illumination of an annunciator panel segment, in turn increasing the risk of them not taking action to correct the condition which activated the master caution.
3. When cockpit voice and flight data recordings are not available to an investigation, this may preclude the identification and communication of safety deficiencies to advance transportation safety.
4. Because the inlets of the ejector pumps are unscreened, there is a risk that FOD in the fuel tank may become lodged in an ejector nozzle and result in a decrease in the fuel delivery rate to the collector tank.
Other Findings:
1. The crew’s decision not to recover or jettison the birds immediately resulted in operation for an extended period with minimal climb performance.
2. The composition and origin of the FOD, as well as how or when it had been introduced into the fuel tank, could not be determined.
3. The SkyTrac system provided timely position information that would have assisted search and rescue personnel if position data had been required.
4. Saskatoon police, firefighters, and paramedics responded rapidly to the accident and provided effective assistance to the survivors.

Factors contributed to the accident are as follows:
• The flight test was not properly well prepared; there was no flight test plan.
• The current and applicable CMM is dissimilar the According to the CASA 212-100 and Garrett TPE331-5 Maintenance Manuals related to flight test requirement after the change of only one engine.
• The left engine was shut down using normal/ ground shut down procedure. It used the fuel shut off switches off followed by pulling the Power Lever rearward to reverse, as indicated by the propeller pitch.
• The right engine most likely shut down by wind milling prior the impact, it was indicated the propellers piston distance position to the cylinder was about normal flight range position and no indication of rotating impact on the blades.
• The Casa Service Bulletin No. 212-76-07 Revision 1 issued dated 23 December 1991 (Anti Reverse) that applicable for Casa 212 -100/200, was not incorporated to this aircraft.
• The PIC with pareses or paralysis vestibular organ or system could not response normally to the three dimensional motion or movement. This condition may the subject more sensitive to suffer Spatial Disorientation (SDO). The SDO is the pilot could not perceived rightly his position motion and attitude to the earth horizontal or to his aircraft or other aircraft and could as the dangerous precondition for unsafe action.
• The Director (DGCA) decree No 30/II/200 issued on 20 February 2009 stated that for issuing medical certificate for pilot after 60th birthday require several additional medical examination items. Point 1.b of this decree states the Video Nystagmography examination.(differed the ICAO Doc 8984).

Controlled flight into terrain.