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Last updated: 15 September 2019
Status:Final
Date:Thursday 20 February 2014
Time:16:41
Type:Silhouette image of generic AT76 model; specific model in this crash may look slightly different
ATR 72-212A (ATR-72-600)
Operator:Virgin Australia Regional
Registration: VH-FVR
C/n / msn: 1058
First flight: 2012-11-12 (1 year 3 months)
Total airframe hrs:2005
Engines: 2 Pratt & Whitney Canada PW127M
Crew:Fatalities: 0 / Occupants: 4
Passengers:Fatalities: 0 / Occupants: 48
Total:Fatalities: 0 / Occupants: 52
Aircraft damage: Substantial
Aircraft fate: Repaired
Location:47 km (29.4 mls) WSW of Sydney, NSW (   Australia)
Phase: En route (ENR)
Nature:Domestic Scheduled Passenger
Departure airport:Canberra Airport, ACT (CBR/YSCB), Australia
Destination airport:Sydney-Kingsford Smith International Airport, NSW (SYD/YSSY), Australia
Narrative:
A Virgin Australia Regional ATR 72-600 sustained damage in an in-flight pitch disconnect event near Sydney, Australia.

= Feb 20 accident =
Flight VA657 departed Canberra, Australia at 16:12 local time with the first officer as the pilot flying. A steeper-than-usual climb was carried out to reduce exposure to turbulence. However, other than the expected turbulence during the first 1,500 ft, there was nothing significant during the climb to FL170.
During cruise, the crew conducted a routine brief for the anticipated arrival to runway 16R, which was expected to be standard except for commencement of descent 5 NM (9 km) earlier than normal to compensate for a tailwind. The captain noted the need to be cognizant of managing airspeed during the descent as the anticipated decreasing tailwind would result in a temporary increase in the indicated airspeed.
The first officer commenced descent into Sydney with the autopilot engaged in vertical speed mode and a target airspeed of 235 kt (15 kt less than the maximum operating speed of 250 kt). The descent was reported to have been initially stable and smooth.
On first contact with Sydney Approach the crew were assigned runway 16L. This was different to the expected runway and required the crew to re-brief the approach and change the instrument approach diagrams and navigational aid frequencies.
Passing 8,500 ft above mean sea level (AMSL), the crew noticed a rapid airspeed increase. The first officer reported that the airspeed trend indicator was 'off the chart', indicating a very rapid increase in airspeed. The first officer reduced engine power and used touch control steering to temporarily disconnect the autopilot before manually raising the aircraft's nose to control the speed. The first officer expected that, in combination, the pitch correction and power reduction would be sufficient to arrest the speed trend.
The first officer reported that the aircraft felt 'heavy', as was normal for this aircraft at that speed, requiring two hands on the controls to move from the then -4° pitch angle.
The captain reported being unsure if the first officer's control inputs would be sufficient to avoid exceeding the maximum operating speed limitation, so put one of his hands on the controls and disconnected the autopilot to raise the nose further.
Shortly after, with both flight crew making simultaneous nose up pitch inputs on the controls, the aircraft rapidly pitched up with an associated increase in the g load. The first officer responded by immediately reversing the control input to nose down. Both flight crew noticed that the controls suddenly felt different and 'spongy'. At about the same time, aural and visual cockpit warnings activated. The crew verified that the aircraft was under control at a stable attitude and speed, observing that it was level or in a slight descent at an airspeed of about 230 kt.
One of the cockpit warnings was 'pitch disconnect', indicating that the left and right elevator control systems had uncoupled from each other. This allowed for independent movement of the left and right elevators via the captain's and first officer's control columns respectively.
The crew consulted the pitch disconnect checklist and worked to identify which control column was free and working normally. After determining that both controls were free, it was decided that the captain would be pilot flying for the remainder of the approach and landing at Sydney Airport. The aerodynamic loads generated during the pitch disconnect resulted in serious injury to the senior cabin crew member and significant damage to the aircraft's horizontal stabiliser.

= Inspection =
Two maintenance engineers were tasked to inspect the aircraft after landing. A readout of the aircraft systems computer revealed a maximum vertical load factor of 3.34 g at 16:41 hours. This load factor was abnormally high and prompted one of the engineers to discuss it with the crew, who were surprised about the high value. The crew added ‘associated with moderate turbulence’ to the maintenance log entry. Since this g-value was outside of the acceptable limits for the aircraft weight, the engineer he grounded the aircraft.
The applicable maintenance was determined to be the 'Inspection after flight in turbulence and/or exceeding VMO'.
That evening a visual inspection was conducted of the wing, using an elevated platform. The engineer also used a torch to inspect the rear fuselage and tail. However, no high-access platform was available, so no close visual inspection was performed on the horizontal stabilizer.
Other maintenance was carried out the next morning, which consisted of among others an operational test of the pitch uncoupling mechanism re-engagement system. The aircraft was then released for service on 13:30 the day after the accident.
Subsequent to the post-occurrence maintenance completed on 21 February 2014, the aircraft was operated on a further 13 flights. The respective flight crews did not record any anomalies or defects during their pre-flight inspections and there were no reports of any abnormal aircraft handling characteristics.

= Feb 25 incident =
On 25 February, aircraft VH-FVR was operated on a scheduled passenger flight from Sydney to Albury, NSW. On descent into Albury, the aircraft passed in close proximity to birds, which alerted the captain to the possibility of a birdstrike on the left side of the aircraft. There were no in-flight indications that a bird had struck the aircraft but after landing, the captain noticed the aircraft’s pitch trim system fluctuated abnormally.
The captain conducted a walk-around inspection and, although there was no evidence of a birdstrike on the left of the aircraft, he identified a dent in the top leading edge of the vertical stabiliser. The captain advised the operator’s maintenance watch who dispatched an engineer to Albury to inspect the aircraft.
The engineer used scissor lift equipment to gain access to, and inspect the stabiliser. He did not find any evidence of a birdstrike, such as blood or feathers. However, the engineer did find indications of significant structural damage to the horizontal stabiliser, and contacted maintenance watch to cancel the following flights. Upon further examination and discussion with the airline, it became evident that the damage found at Albury was probably a consequence of the occurrence on 20 February.

Probable Cause:

Findings:
From the evidence available, the following findings are made regarding the in-flight upset and inadvertent pitch disconnect involving ATR 72 aircraft, VH-FVR on 20 February 2014 resulting in cabin crew injury and serious aircraft damage. A post-event maintenance inspection was carried out but the aircraft damage was not detected. Consequently, the aircraft was operated for another 13 flights over 5 days before the damage was identified.

Contributing factors:
- During the descent, when the sterile flight deck policy was applicable, the flight crew engaged in non-pertinent conversation. This distracted the crew and probably reduced their ability to monitor and respond to fluctuations of airspeed.
- While passing through about 8,500 ft on descent into Sydney, the aircraft encountered a significant windshear that resulted in a rapidly decreasing tailwind. This led to a rapid increase in the airspeed, with the airspeed trend vector likely indicating well above the maximum operating speed (VMO).
- Although the first officer (pilot flying) was in the process of attempting to control the airspeed, in response to the unexpectedly high airspeed trend indication, and their proximity to VMO, the captain (pilot not flying) perceived a need to immediately intervene, and made pitch control inputs before following the normal take-over procedure and alerting the first officer.
- The addition of the captain’s and first officer’s nose-up control inputs resulted in a pitching manoeuvre that exceeded the limit load factor for the aircraft of 2.5 g.
- The magnitude of the captain's nose-up control input was probably greater than he intended, due to his response to a high stress level, but increased the probability that the aircraft's limit load factor would be exceeded.
- Shortly after the captain initiated the nose-up control inputs, the first officer reversed his control input. The differential forces in the left (captain) and right (first officer) pitch control systems were sufficiently large to inadvertently activate the pitch uncoupling mechanism, disconnecting the left and right pitch control systems.
- Given the high airspeed, the asymmetric elevator deflections that occurred immediately following the pitch disconnect event resulted in aerodynamic loads on the tailplane that exceeded its strength and damaged the horizontal stabiliser.
- The design of the ATR 72 pitch control system resulted in limited tactile feedback between the left and right control columns, reducing the ability of one pilot to detect that the other pilot is making control inputs. In addition, there were no visual or auditory systems to indicate dual control inputs. (Safety issue)

Accident investigation:
cover
Investigating agency: ATSB
Status: Investigation completed
Duration: 5 years and 3 months
Accident number: AO-2014-032
Download report: Final report

Classification:
Normal landing

Follow-up / safety actions

ATSB issued 6 Safety Recommendations

Show all...

Photos

photo of ATR-72-600-VH-FVR
accident date: 20-02-2014
type: ATR 72-600
registration: VH-FVR
photo of ATR-72-600-VH-FVR
accident date: 20-02-2014
type: ATR 72-600
registration: VH-FVR
photo of ATR-72-600-VH-FVR
FDR graph
photo of ATR-72-600-VH-FVR
FDR graph
 

Map
This map shows the airport of departure and the intended destination of the flight. The line between the airports does not display the exact flight path.
Distance from Canberra Airport, ACT to Sydney-Kingsford Smith International Airport, NSW as the crow flies is 236 km (147 miles).
Accident location: Exact; as reported in the official accident report.

This information is not presented as the Flight Safety Foundation or the Aviation Safety Network’s opinion as to the cause of the accident. It is preliminary and is based on the facts as they are known at this time.
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