TOTAL POWER LOSS
At 0835 Eastern Standard Time on 26 September 2011, a flight instructor and student pilot in a Cessna Aircraft Company 152 registered VH-HCE (HCE), were operating at Bankstown Airport, New South Wales, on a training flight.
The student was in the early stages of obtaining a private pilot licence. The instructor planned on demonstrating a series of rejected takeoffs followed by circuits encompassing emergency procedures.
Pre-flight checks were completed with the instructor obtaining a combined sample of fuel from both wing tanks and the fuel strainer. The instructor showed the combined sample to the student with both agreeing that the sample looked and smelt normal with no impurities present. The engine run-up was conducted with no problems identified.
The instructor obtained clearance from air traffic control (ATC) to conduct a series of practice rejected take-offs on runway 11/29 centre. Once satisfied that the student had demonstrated the learning outcomes, the instructor obtained circuit clearance from ATC, departing from runway 11 Centre for circuits to Runway 11 Right.
The student conducted the initial circuit before handing control to the instructor who demonstrated a go-around. The instructor then demonstrated a glide circuit before handing control back to the student to complete the approach and touch-and-go. The student completed this procedure and the aircraft became airborne approximately two thirds distance from the Runway 11 Right threshold.
Engine power loss
At an altitude of approximately 200 ft above ground level, the instructor heard the engine noise reducing and observed the engine RPM decreasing. The instructor immediately assumed control and lowered the nose of the aircraft to maintain airspeed. With engine power further reducing, the instructor determined that ability to land on the remaining runway was restricted and identified a clear grassed area at his 10 to 11 o’clock position.
The aircraft was manoeuvred for an emergency landing and a MAYDAY declared to ATC. The instructor reported that there was insufficient time to conduct troubleshooting or to place the flaps in the down position as he was focussed on conducting the forced landing.
Shortly after the main wheels contacted the ground, the engine power increased significantly. The instructor immediately pulled the throttle to idle, having assessed that landing was the safest option. As the engine power reduced to idle, the nose wheel contacted the ground and detached. The aircraft nosed-over and slid a short distance before coming to rest inverted. After assessing that the student was uninjured, the instructor asked the student to immediately vacate the aircraft before exiting the aircraft himself.
The instructor held a Grade 2 (aeroplane) flight instructor licence with night VFR endorsement with a total of 2,400 flying hours. He commenced flight training in 2007 and had been employed as an instructor by the same training school since 2008.
The student commenced instruction 16 days prior to the accident flight and had a total of 9.2 hours.
HCE was a tricycle, fixed gear, utility aeroplane manufactured in the United States in 1979. At the time of the accident the aircraft had a total time in service of 16,604 hours.
HCE had been fuelled to full capacity on the afternoon of Friday, 23 September 2011. The aircraft was operated for a 1.1 hour circuit flight the following morning, then parked in the open until the accident flight on Monday, 26 September 2011.
The aircraft fuel system consisted of two standard fuel tanks (one in each wing), a fuel shutoff valve, fuel strainer, manual primer and carburettor. The system had three fuel drain locations – two wing tank sump drains and a fuel strainer drain.
The Bureau of Meteorology (BoM) released a METAR at 0700 on the morning of the accident indicating that 27.8 mm of rain was recorded at Bankstown Airport in the previous 24 hours from 0900, Sunday, 25 September 2011. Additional data from the BoM indicated that while the aircraft was parked at Bankstown Airport a total of 43.4 mm of rain was recorded.
The Australian Transport Safety Bureau (ATSB) was advised that HCE landed on firm ground in long grass. About 15 m from the touchdown point there was a 300 mm high mound of dirt (invisible in the long grass) which the nose wheel struck causing it to collapse.
Post-accident fuel sample
While the aircraft was still inverted, a sample of the fuel from the main fuel filter was drawn through the primer line pickup. The fluid in that sample was identified as water with no fuel evident.
A fuel sample could not be obtained from the carburettor due to damage sustained in the accident.
When the aircraft was righted, further fuel samples were drawn from both wing tanks. The left tank indicated clear fuel with the right tank showing significant water present in that fuel sample.
Both fuel tank filler caps and receptacles were inspected. The left wing filler cap appeared to seal correctly. The right filler cap and seal showed signs of wear, but was still considered to be in a serviceable condition.
The right fuel tank receptacle lip showed signs of significant water contact in the form of surface rust. The receptacle was also found to be distorted, with the forward lip appearing to have been pushed down along its inner edge.
Water contamination was identified in the post-accident fuel samples taken from the fuel filter and the right fuel tank.
Surface rust on the right tank fuel cap receptacle indicated that water had most likely entered the system through that point during the heavy rainfall that occurred the previous days while the aircraft was parked in the open.
The water contamination in the fuel was not identified during the pre-flight fuel drain check that was conducted by the instructor and witnessed by the student.
Whether or not the ATSB identifies safety issues in the course of an investigation, relevant organisations may proactively initiate safety action in order to reduce their safety risk. The ATSB has been advised of the following proactive safety action in response to this occurrence.
As a result of this occurrence, the aircraft operator advised the ATSB that they were taking the following safety actions:
• Immediately following the incident, the operator inspected their fleet with one additional aircraft identified as having water present in the fuel system.
• Information evenings with students to discuss recent fuel contamination issues that resulted in partial or full loss of power were conducted.
• Compulsory instructor training on the incident as well as specific training on the Cessna type fuel system was conducted.
• Emergency checklists were reviewed in particular the way emergency checks were instructed and assessed, looking specifically at the use of memory item checks at low altitudes.
Reported engine water contamination events
A review of ATSB accident and incident data between 1998 and 2011, involving water contamination in single engine Cessna aircraft highlighted 18 events.
• C150/152 8 events
• C172/C182 4 events
• C206/C210 6 events
Given the volume of single-engine aircraft operations in Australia, 18 reported water contamination events is relatively low, but this accident is a prompt that such events can potentially have catastrophic outcomes. Operators and pilots are reminded that following periods of heavy rain, or aircraft down time, extra vigilance is required during pre-flight checks to ensure that any fuel carried or sourced is free of water contamination.
AO-2011-118: VH-HCE, Total power loss
Date and time: 26 September 2011, 0858 EST
Location: Bankstown Airport, New South Wales
Occurrence category: Accident
Occurrence type: Total power loss
Aircraft registration: VH-HCE
Aircraft manufacturer and model: Cessna Aircraft Company, 152
Type of operation: Flying training – dual
Persons on board: Crew – 2 Passengers – Nil
Injuries: Crew – Nil Passengers – Nil
Damage to aircraft: Serious