Pilot information
Instructor
General information
The instructor held an Air Transport Pilot Licence (Aeroplane), a flight instructor rating with a Grade 1 training endorsement and a Class 1 aviation medical certificate.
At the time of the accident flight, the instructor had over 3,200 hours of flying experience, of which over 170 hours were on the DA40.
Spin training and knowledge
The regulations required that an instructor complete training in developed spin recovery techniques prior to obtaining an instructor rating. After this initial training, there was no regulatory requirement for an instructor to undergo further spin training.
A review of the instructor’s training records showed he underwent developed spin recovery training on 18 January 2011, while training for his initial instructor rating. His employment records and logbooks show no subsequent spin training or assessment. However, there was no requirement to record spins or spin training in pilot logbooks.
Students of the flying school later reported that the instructor advised them of a recent incipient spin (see Spin classifications and recovery) occurrence. About a week prior to the accident flight, the same pairing of student and instructor as the accident flight entered an incipient spin during advanced stall recovery training. The instructor had described the student mishandling the recovery of the incipient spin which led to the aircraft entering an incipient spin in the opposite direction. The instructor then took control of the aircraft and recovered to stable flight.
On the day before the accident, the instructor conducted the ground school training of another pilot as part of the training for the issue of an instructor rating. During this training, the pilot presented a briefing on advanced stall recovery training to the instructor, which the instructor reviewed, took notes and provided feedback.
The ATSB assessment of the instructor’s feedback and notes indicated that the instructor’s knowledge of incipient spin recovery was consistent with established guidelines.
Student
The student was not required to hold, and did not hold, a flight crew licence. The student held a Class 2 aviation medical certificate and had 58 hours of flying experience, of which 19 hours were on the DA40.
Medical information
The ATSB found no indicators that increased the risk of either the instructor or student experiencing a level of fatigue known to have an effect on performance.
Witness reports from family and acquaintances indicate that the instructor and student were in good health and a good mental state prior to the flight. A review of the instructor and student’s medical history and the instructor’s mobile phone data found no indication that the health and or mental state of the instructor or student contributed to the accident. Post-mortem and toxicological examinations of the instructor and student did not reveal any medical issues that may have contributed to the accident.
Wreckage examination
The aircraft impacted terrain at an elevation of 167 ft above mean sea level. On-site examination of the wreckage and surrounding ground marks indicated that the aircraft impacted terrain left wing first, nose-down and rotating to the left at low forward speed. This was consistent with a left upright spin (Figure 2).
The forward fuselage separated at the engine firewall. The wings, centre fuselage, and rear fuselage all separated in a direction consistent with a left spin. Evidence from examination of the engine and propeller was consistent with the engine producing low power at the time of the accident. Although the throttle position could not be determined from the wreckage, evidence from the engine and propeller corresponds to the recommended power setting for spin recovery (idle).
The positions of the rudder, ailerons and elevator at the time of the accident could not be determined, however the wing flaps were retracted. Both fuel tanks were ruptured and the fuel selector was selected to the left fuel tank.
Figure 2: Wreckage comparison
The figure provides a comparison between the wreckage of VH-MPM and the expected wreckage pattern for a spin accident as described by Wood and Sweginnis (1995), Aircraft Accident Investigation.
Source: ATSB and Endeavour Books
Examination of the wreckage and maintenance documentation found no evidence of a pre-existing problem that may have contributed to the accident. The accident was not survivable.
Purpose of the flight
The purpose of the flight was to prepare the student for an upcoming RPL flight test. On the day before the accident, the instructor and student conducted a simulated RPL flight test in accordance with Civil Aviation Safety Authority (CASA) form 61-1486 - Recreational Pilot Licence – Aeroplane. During this flight, the instructor determined that the student was not ready for the test. For the flight on the day of the accident, the instructor and student intended to conduct a similar flight to revise the sequences requiring attention.
A handwritten note (Figure 3) was found in the cockpit and was determined to relate to the accident flight. The note listed the following sequences to be conducted in the training area:
- unusual attitudes
- steep turns
- stalls
- advanced stalls
- practice forced landing
- precautionary search and landing.
The order of sequences and markings on the note aligned with the aircraft movements captured by radar. The note indicated that the sequences up to and including stalls had been completed. At the time the aircraft entered the spin, the instructor and student were likely conducting the next incomplete item on the list, which was advanced stall recovery training.
Figure 3: Instructor’s note from accident flight
Source: Queensland Police annotated by ATSB
The advanced stall recovery training component of the simulated RPL test required a student to demonstrate recovery from incipient spins (see Aircraft information) and stalls conducted with different engine power settings, aircraft configurations and entry attitudes.
This sequence requires an instructor or student to configure and manoeuvre an aircraft in a manner that is conducive to an incipient spin. An instructor may also deliberately induce an incipient spin. A student must then demonstrate the correct recovery to stable flight.
The aircraft should not be permitted to enter a developed spin, however, slow recovery action or mishandling during the incipient spin recovery may lead to an aircraft entering a developed spin. If the student does not demonstrate prompt and correct recovery actions, an instructor should take control to prevent the aircraft entering a developed spin.
Aircraft information
General information
The Diamond Aircraft Industries DA40-180 is a four-seat, low-wing, fixed-tricycle-undercarriage aircraft with a glass and carbon fibre reinforced polymer construction. It has a single reciprocating engine driving a variable pitch two bladed propeller (Figure 4). The aircraft was equipped with dual controls for the student and instructor and Garmin G1000 instrumentation. It was not equipped with an aircraft parachute system.
Figure 4: VH-MPM
Source: Operator
VH-MPM was manufactured in 2006 and had a total time in service of 678 hours. It had a valid maintenance release showing no outstanding issues and the last scheduled maintenance was completed on 22 August 2017.
Weight and balance
The aircraft was loaded within weight and longitudinal balance limits for the duration of the flight.
Fuel system and distribution
The aircraft was fitted with a main and auxiliary fuel tank with a combined capacity of 92.5 L in each wing, providing a total fuel capacity of 185 L. A fuel tank selector, positioned on the centre console between the student and instructor, provided for the selection to use fuel from the left or right fuel tanks or to select the fuel off.
Fuel records indicated that the aircraft was loaded with 139 L of fuel prior to departure, sufficient for the planned flight.
The aircraft flight manual contained the following fuel limitation:
Maximum permissible difference between right and left tanks: 8 US gallons (approximately 30 L)
It was not possible to determine the fuel level in each tank prior to take-off or during the flight. The fuel tanks ruptured during the accident and a significant amount of fuel escaped from each tank. Therefore, the distribution of fuel on board at the time of the accident could not be determined.
Intentional spinning limitation
The aircraft flight manual included a limitation stating that intentional spinning was not permitted in the aircraft.
The manufacturer provided the following comment regarding the conduct of incipient spins in VH-MPM:
The DA40 used in this accident is not approved for intentional spins, incipient or otherwise. Inducing a spin is outside of the approved envelope of the DA40.
The manufacturer also advised:
Using rudder deflection to enter an incipient spin, even if the aircraft is immediately recovered from that incipient spin, is an intentional spin and therefore not allowed to be performed with a DA40.
Certification spin testing
The aircraft type was certified in the Normal and Utility categories in accordance with European Aviation Safety Agency (EASA) Joint Aviation Regulations (JAR) part 23.
The aircraft was not approved for intentional spinning, but had been evaluated to meet the requirements of JAR Part 23.221, namely:
a. Normal Category aeroplanes. A single engined, normal category aeroplane must be able to recover from a one-turn spin or a three-second spin, whichever takes longer, in not more than one additional turn, after initiation of the first control action for recovery. In addition –
1. For both the flaps-retracted and flaps-extended conditions, the applicable airspeed limit and positive limit manoeuvring load factor must not be exceeded;
2. No control forces or characteristic encountered during the spin or recovery may adversely affect prompt recovery;
3. It must be impossible to obtain unrecoverable spins with any use of the flight or engine power controls either at the entry into or during the spin; and
4. For the flaps extended condition, the flaps may be retracted during the recovery but not before rotation has ceased.
b. Utility category aeroplanes. A utility category aeroplane must meet the requirements of sub-paragraph (a).
The certification report stated that the aircraft exhibited prompt incipient spin recovery behaviour within the certification requirements. The manufacturer was not required to and did not test the aircraft for fully developed spin behaviour and recovery.
Developed spin recovery
While, the flight manual prohibited intentional spinning, the manual provided the procedure shown in Figure 5 to assist in recovery from an unintentional spin.
Figure 5: Unintentional spin recovery checklist
Source: Diamond Aircraft
Aerodynamic spins
An aerodynamic spin is a sustained spiral descent in which an aircraft’s wings are in a stalled condition, with one wing producing more lift than the other. This difference in lift sustains the rotation and keeps the aircraft in the spin. The nose angle can also vary considerably. In a fully developed, upright, left spin, an aircraft will simultaneously roll[5] to the left while yawing[6] to the left, making a vertical corkscrew path through the air. A spinning aircraft will descend more slowly than one in a vertical dive and it will also have a lower airspeed, which may oscillate.
Spin classifications and recovery
The United States Federal Aviation Administration publication Airplane Flying Handbook, Chapter 4: Maintaining Aircraft Control: Upset Prevention and Recovery Training provides the following further information regarding spin classification and recovery:
Incipient phase
The incipient phase occurs from the time the airplane stalls and starts rotating until the spin has fully developed. This phase may take two to four turns for most airplanes. In this phase, the aerodynamic and inertial forces have not achieved a balance. As the incipient phase develops, the indicated airspeed will generally stabilize at a low and constant airspeed and the symbolic airplane of the turn indicator should indicate the direction of the spin. The slip/skid ball is unreliable when spinning.
The pilot should initiate incipient spin recovery procedures prior to completing 360° of rotation. The pilot should apply full rudder opposite the direction of rotation. The turn indicator shows a deflection in the direction of rotation if disoriented.
Incipient spins that are not allowed to develop into a steady-state spin are the most commonly used maneuver in initial spin training and recovery techniques.
Developed phase
The developed phase occurs when the airplane’s angular rotation rate, airspeed, and vertical speed are stabilized in a flightpath that is nearly vertical. In the developed phase, aerodynamic forces and inertial forces are in balance, and the airplane’s attitude, angles, and self-sustaining motions about the vertical axis are constant or repetitive, or nearly so. The spin is in equilibrium. It is important to note that some training airplanes will not enter into the developed phase but could transition unexpectedly from the incipient phase into a spiral dive. In a spiral dive the airplane will not be in equilibrium but instead will be accelerating and G load can rapidly increase as a result.
The New Zealand Civil Aviation Authority booklet, Spin Avoidance and Recovery provides further useful information. The booklet also provides the following guidance regarding developed spin recovery:
The minimum altitude loss for a textbook recovery will be about 1000 to 1500 feet.
The Australian Civil Aviation Safety Authority did not provide guidance defining the incipient spin manoeuvre.
During the investigation, the ATSB discussed the manoeuvre with the operator’s Head of Operations, the operator’s previous Head of Operations and the Head of Operations of the instructor’s previous employer.
- The operator’s Head of Operations described conducting ‘wing-drop’ manoeuvres in the DA40.
- The previous Head of Operations commented that incipient spins in the DA40 were risky as spins were prohibited for the aircraft type. This made training in the aircraft difficult.
- The Head of Operations of the instructor’s previous employer advised that the flight test requirement was to conduct ‘wing-drop stalls’ and that this did not constitute spinning.
Civil Aviation Safety Authority
Appropriate use of aircraft
CASA provided the following comment regarding training operations using aircraft which are not approved for intentional spins:
If the operator does not have a suitable type of aircraft for a particular kind of training, then CASA would expect the operator to make appropriate arrangements to acquire or loan a suitable aircraft. The Head of Operations of a training operator has the responsibility to ensure the proper allocation and deployment of aircraft.
Incorrect guidance
While the ATSB assessed that the instructor’s incipient spin recovery knowledge was consistent with established guidelines and did not contribute to the accident, the investigation identified incorrect incipient spin recovery guidance provided by CASA.
The CASA publication Flight Instructor Manual, provides the following guidance for incipient spin recovery:
RECOVERY FROM THE INCIPIENT STAGE
As soon as the aeroplane has stalled and commenced to yaw take the appropriate recovery action. Increase power, apply sufficient rudder to prevent further yaw and ease the control column forward sufficiently to un-stall the aeroplane. Point out that if power is to materially assist recovery action it must be applied before the nose of the aeroplane has pitched too far below the horizon otherwise its use will only increase the loss of height.
Increasing engine power prior to an application of sufficient rudder to prevent further yaw and applying sufficient nose-down elevator un-stall the wings as described is inconsistent with established guidelines and manufacturer guidance.
The United States Federal Aviation Administration publication Airplane Flying Handbook, Chapter 4: Maintaining Aircraft Control: Upset Prevention and Recovery Training provides the following guidance, consistent with established guidelines, regarding spin recovery:
To accomplish spin recovery, always follow the manufacturer’s recommended procedures. In the absence of the manufacturer’s recommended spin recovery procedures and techniques, use the spin recovery procedures in the spin recovery template. If the flaps and/or retractable landing gear are extended prior to the spin, they should be retracted as soon as practicable after spin entry.
Spin recovery template:
1. Reduce the Power (Throttle) to Idle
2. Position the Ailerons to Neutral
3. Apply Full Opposite Rudder against the Rotation
4. Apply Positive, Brisk, and Straight Forward Elevator (Forward of Neutral)
5. Neutralize the Rudder After Spin Rotation Stops
6. Apply Back Elevator Pressure to Return to Level Flight.
The handbook also provides further guidance regarding power use during spin recovery:
Reduce the Power (Throttle) to Idle. Power aggravates spin characteristics. It can result in a flatter spin attitude and usually increases the rate of rotation.
CASA advised the ATSB that this matter will be referred to Safety Education for review and correction as required.
Meteorological information
Data recorded by the automatic weather station at Beaudesert, Queensland, 7 km southeast of the accident site, was provided by the Bureau of Meteorology. The site recorded observations at 30-minute intervals. The recorded observations from 13 minutes prior to, and 17 minutes after the accident, indicated that light winds and clear conditions prevailed.
Video footage obtained from another aircraft operating in the Archerfield training area at the time of the accident showed smooth flying conditions, visibility in excess of 10 km and no cloud at, immediately above, or below 4,500 ft.
Flight data recording
The aircraft was not required to be, and was not, fitted with a flight data recorder.
The aircraft was equipped with Garmin G1000 instrumentation. When fitted with a data card in the relevant port, this system was capable of recording multiple parameters relating to the operation of the aircraft and its systems.
The aircraft did not have a data card installed in the relevant port during the accident flight, therefore no data was recorded.
Similar occurrences
A review of the ATSB occurrence database for the period 2009 to 2019 found the following occurrences involving incipient spin training in aircraft are not approved for intentional spinning:
Occurrence 201704820 – VH-YTE – S.O.CA.T.A. – Groupe Aerospatiale TB-10
At the end of the advanced stalling lesson, the instructor was intending to observe the student’s wing drop recovery. The instructor initiated a right wing drop, however the student’s incorrect use of full aileron during recovery led to spin entry to the right. The instructor took control and recovered the aircraft. The aircraft completed two full rotations and lost 1,200 ft during recovery.
Occurrence 201403058 – VH-EZT – Czech Sport Aircraft – PIPERSPORT
While practicing incipient spins, the instructor initiated a left wing drop. Once the aircraft stalled, the student was asked to recover. The student reduced power with slight delay and applied the incorrect rudder input. The aircraft then turned further left and the instructor directed the application of right rudder. The student did not respond and the instructor took control and initiated spin recovery. The aircraft continued to rotate before recovering about 20 to 30 seconds later. During the recovery the aircraft maximum design load factor was exceeded by 0.1G.[7]
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