Published: 18 January 2019
Section 21 (2) of the Transport Safety Investigation Act 2003 (the Act) empowers the Australian Transport Safety Bureau (ATSB) to discontinue an investigation into a transport safety matter at any time. Section 21 (3) of the Act requires the ATSB to publish a statement setting out the reasons for discontinuing an investigation.
On 19 November 2015, the ATSB was notified of an occurrence involving an Airbus A321, operated by Jetstar Airways. During take-off on 29 October 2015, the flight crew encountered difficulty rotating the aircraft. A subsequent passenger count found that passengers had not been allocated seats in accordance with the aircraft’s weight and balance requirements, making the aircraft nose heavy.
The ATSB initiated investigation AO-2015-139 on 23 November 2015. Later, the ATSB became aware of three previous events involving the same operator. They were initially investigated as related occurrences as part of AO-2015-139. On 8 September 2017, due to the common factors involved, the ATSB changed the investigation type to a safety issues investigation and it was re‑numbered AI-2015-139. A fifth occurrence, also involving the same operator, was added to the investigation scope in October 2017. A summary of each occurrence is provided at the end of this notice.
On these five separate occasions, and probably others, aircraft were loaded with incorrect passenger distributions or with incorrect passenger numbers used to determine the aircraft's weight and balance. This placed increased operational pressure on flight and cabin crews and, on at least one occasion, adversely affected aircraft performance during take-off. Records show that there were other flights where erroneous passenger loading was discovered before pushback.
Four of the occurrences followed the introduction of a new type of mobile boarding manager (MBM) device used to scan passenger boarding passes and tally the passengers as they boarded. In each case, technical faults and/or erroneous operation of the MBM led to incorrect passenger loading information being provided to flight crews. On two of those occasions, passenger seating allocations were erroneous after a late change of aircraft type.
The ATSB obtained and analysed a large amount of evidence, mostly information from the operator, and interviewed relevant operational personnel during the initial occurrence investigation. However, there were significant and ongoing difficulties in obtaining documentation associated with the project to introduce then new MBM in 2015 and some related matters.
The ATSB strives to use its limited resources for maximum safety benefit and considers that:
- The operator’s organisational context has significantly changed in the 3 years since the investigation began, likely making some of the organisational aspects of the investigation no longer relevant.
- The operator conducted internal safety investigations into the relevant occurrences, and there is significant overlap between the operator’s findings and the ATSB’s provisional findings. The operator has taken action to address those issues in regular consultation with the Civil Aviation Safety Authority.
- The potential safety issues identified to date provide only limited benefit to the greater aviation industry.
- Significant further investigation work would be required to obtain sufficient information to develop provisional investigation findings into safety issues that meet the ATSB’s standards for rigour and defensibility.
- Based on the available information, the risk controls currently in place and the operating context, the ATSB considers any undetected passenger loading problem associated with the identified limitations were very unlikely to have a significant operational impact.
Consequently, the ATSB has discontinued this investigation, and will communicate all additional provisional safety issues and learnings to the operator to reduce future risk. These included limitations in the management of passenger load discrepancies and late aircraft changes, support for concourse staff, management of the then MBM development project, and the framework for operational change. The investigation information collected and analysed to date remains available as reference material for future ATSB investigations.
Summary of occurrences
- On 16 June 2015 an Airbus A321 registered VH‑VWY was being prepared for a flight from Sydney, New South Wales (NSW), to Hobart, Tasmania, after the scheduled Airbus A320 aircraft became unavailable. After the passengers had boarded, the flight crew identified that the aircraft was loaded too nose heavy for take-off, because the passenger distribution in the cabin was too far forward. To balance the aircraft, the captain ordered the underfloor cargo to be rearranged in a manner that contravened the aircraft’s loading requirements and then continued the planned flight. It was later established that passenger seating allocations had been determined using the seat map for an A320 instead of an A321.
- While processing passenger data after an Airbus A320 registered VH‑VFQ departed Brisbane, Queensland for Newcastle, NSW on 6 October 2015, ground staff discovered a passenger count discrepancy between the final boarding report and the central check-in computer. The flight crew were contacted and an in-flight passenger count found that 15 more passengers were aboard than accounted for during pre-flight planning. This affected the flight crew’s weight and performance calculations, but the minor effect of the increased weight had not been noticed by the crew on take-off. The flight crew amended the calculations prior to approach and landing.
- During a flight from Brisbane to Melbourne, Victoria on 19 October 2015, the crew of an Airbus A320 registered VH‑VQG identified a passenger count discrepancy after a cabin crewmember mentioned the large number of passengers on board to the flight crew. They found that 15 more passengers were aboard than accounted for during pre-flight planning. This affected the flight crew’s weight and performance calculations, but the minor effect of the increased weight had not been noticed by the crew on take-off. The flight crew amended the calculations prior to approach and landing.
- On 29 October 2015, an Airbus A321 registered VH‑VWT was being operated from Melbourne to Perth, Western Australia, after the scheduled Airbus A320 aircraft became unavailable. During take-off, the pilot flying needed significantly more control input than normal to rotate the aircraft. After conducting a passenger count, the crew found that the passenger distribution in the cabin was too far forward, making the aircraft nose heavy. The crew moved six passengers to the rear zone for the remainder of the flight, and amended the weight and balance calculations prior to approach and landing. It was later established that passenger seating allocations had been determined using the seat map for an A320 instead of an A321.
- While processing passenger data after an Airbus A320 registered VH‑VGR departed Sydney for Melbourne on 23 October 2017, ground staff discovered an unusual discrepancy between the provisional and final boarding reports. The flight crew were contacted and an in-flight passenger count found that 22 more passengers were on board than accounted for during pre-flight planning. This affected the flight crew’s weight and performance calculations, but the minor effect of the increased weight had not been noticed by the crew on take-off. The flight crew amended the calculations prior to approach and landing.
The information contained in this web update is released in accordance with section 25 of the Transport Safety Investigation Act 2003.
 Rotate: lift an aircraft’s nose on take-off.
 The operator reported to the ATSB that it has subsequently introduced a fully redesigned MBM without these issues.
|Date:||24 November 2015||Investigation status:||Discontinued|
|Investigation level:||Complex - click for an explanation of investigation levels|
|Investigation phase:||Final report: Dissemination|
|Occurrence type:||Loading related|
|Release date:||18 January 2019|