On 8 March 2014, a Malaysia Airlines Boeing 777 disappeared during a flight between Kuala Lumpur and Beijing. The flight was MH370 and there were 239 passengers and crew on board. No evidence of a crash had been reported and the last radio transmission from the crew came less than an hour into the flight.
A week later, additional information suggested that flight MH370 had diverted from its intended course, with analysts determining that the aircraft’s route had probably tracked south to an area far off the Western Australian coast, in the southern Indian Ocean.
On 17 March, the Australian Government assumed responsibility for search operations in Australia’s search and rescue region. Defence played a key role in supporting the Australian Maritime Safety Authority as the lead search and rescue agency. The following three profiles highlight specific areas of activity.
Defence establishments in Western Australia, notably Fleet Base West and RAAF Base Pearce, quickly ramped up to support additional ships and aircraft from a number of other nations, becoming an important focal point for the search and rescue effort.
With the support of RAAF AP-3C Orion long-range maritime patrol aircraft, a visual and radar search of an extensive area more than 2,000 kilometres south-west of Perth began on 18 March. Within 24 hours, the United States Navy and Royal New Zealand Air Force joined the task. On 19 March, HMAS Success was deployed from Fleet Base West to the search area; in the following weeks it was joined by HMAS Perth and HMAS Toowoomba. RAAF Base Pearce and Perth International Airport became the hubs for air search efforts involving more than 21 military aircraft and civilian jets from
Australia, Malaysia, New Zealand, the United States, China, Japan and South Korea. Three hundred and forty-five air sorties were conducted during 42 days of searching.
Joint Task Force 658 was established on 26 March to assist with coordination of the international and Australian search efforts as part of Operation Southern Indian Ocean.
On 30 March, Prime Minister Tony Abbott announced the appointment of the former Chief of the Defence Force, Air Chief Marshal Angus Houston, as the lead for coordinating the Australian Government’s response.
A number of acoustic detections were made by HMS Echo, the Chinese ship Haixun 01, Australian Defence Vessel Ocean Shield and RAAF Orion aircraft that needed to be analysed. After detailed analysis by the Australian Joint Acoustic Analysis Centre and the Defence Science and Technology Organisation (DSTO), all detections were eventually discounted. On 14 April, Ocean Shield, with an onboard team of civilian contractors supported and funded by the US Navy, deployed the Automated Underwater Vessel Bluefin 21 to conduct a side-scan sonar survey of the ocean floor. In conjunction with DSTO, the RAAF also trialled a modified Orion aircraft with an experimental acoustic processor and modified sonobuoys enabling the aircraft to detect flight data recorder signals underwater.
Using International Maritime Satellite (Inmarsat) data collected via the hourly aircraft-to-satellite ‘handshake’ process, an international team of aircraft investigators discerned that MH370 had flown for at least six hours from its last contact. The team identified two broad swathes of the earth’s surface, reaching far to the north and south, as potential flight paths.
An RAAF AP-3C Orion flies past Australian Defence vessel Ocean Shield on a mission to drop sonar buoys to assist in the acoustic search in support of Operation Southern Indian Ocean.
Defence’s Australian Geospatial-Intelligence Organisation (AGO) joined an international effort to search landing zones in the northern hemisphere; however, the possibility of MH370 having landed safely was soon ruled out.
Further analysis of the Inmarsat data enabled the international team to determine that MH370 had flown south, away from potential landing zones. At the same time, about 10 days after the aircraft’s disappearance, satellite imagery of the far southern Indian Ocean revealed large debris floating on the water.
The AGO mobilised to take on the enormous task of searching the southern latitudes for signs of MH370. Cloud cover and the sea state made the search for floating debris challenging. The resources of partner satellite imagery organisations around the world were coordinated and approximately 850,000 square kilometres of ocean were scanned. The AGO was supported by private industry, which provided 386 images covering 1.56 million square kilometres at no cost.
The AGO’s work directly supported the Australian Maritime Safety Authority (AMSA), the agency initially responsible for determining the location of the MH370 wreckage and the aircraft’s black box.
Around-the-clock reporting from the AGO helped AMSA plan daily aircraft search operations.
AMSA also received a steady stream of unsolicited debris sightings based on publicly available imagery. The AGO and partner organisations analysed this crowd-sourced imagery and provided AMSA with a confidence rating for each sighting. Using imagery analysis, the AGO was able to narrow down the list of more than 300 crowd-sourced sightings to two low-confidence identifications.
When the aerial search ended on 28 April, the AGO had spent around 4,500 hours searching approximately 850,000 square kilometres of the southern Indian Ocean and had provided AMSA with 61 possible debris detections for further investigation.
The Australian Transport Safety Bureau assumed responsibility as the lead search agency on 28 April. Defence has continued to provide support and expertise to the search.
Staff from DSTO have been complimented by Australian Transport Safety Bureau Chief
Commissioner Martin Dolan for their work in tracing movements of missing MH370.
‘We have been very impressed with the work of the DSTO team during what I know were very trying times for your organisation’, he said.
‘The speed with which you all fitted into an ongoing arrangement, the technical ability and responsiveness of the DSTO team and the collaborative spirit of the whole exercise are a fine example of cooperation towards a great result.’
Determining the aircraft’s location was a mammoth task with few clues. The Australian Defence Vessel Ocean Shield deployed a towed pinger locator to detect the sonar ping from the underwater locator beacon attached to the aircraft’s black box. The beacons emit a signal only until their batteries expire. As the likely end-of-battery life drew closer, faint pings were heard, although they were of uncertain origin.
The Australian Transport Safety Bureau asked DSTO to independently assess the acoustic signals recorded by the pinger locator. Within 24 hours of receiving the data, DSTO advised that the signals did not appear to have originated from an aircraft underwater locator beacon on the seafloor. Subsequently, DSTO was also asked to review acoustic recordings available from the worldwide network of Comprehensive Nuclear Test Ban Treaty Organization seafloor hydrophone arrays. This analysis confirmed an earlier Curtin University assessment that the hydrophone array signals did not originate from MH370, either from its impact with the ocean surface or from a subsequent implosion of equipment on board the aircraft as it sank.
DSTO was then asked to join an international working group to independently reprocess Inmarsat data and provide a better estimate of the search zone. While the team was accustomed to coping with noisy and uncertain data, the problem required some particularly innovative thinking. The team developed and
calibrated new statistical data-processing techniques to analyse the sparse satellite data and predict the flight path of the aircraft. Such was the sensitivity of the analysis that even the effect of the earth’s shadow on the satellite had to be taken into account. Results from the newly developed mathematical models influenced the choice of the future search area and formed a key component of the Australian Transport Safety Bureau’s public report released on 26 June.
Prime Minister Abbott called Operation Southern Indian Ocean an ‘unprecedented’ coalition of countries working cooperatively in the search for MH370. By 28 April, 4.5 million square kilometres had been searched. The operation involved 2,999 flying hours and a combined total of 480 search days by the 17 ships and one submarine that were involved in surface operations.
Despite a series of possible acoustic detections and many sightings of objects of interest, no physical evidence was found. The DSTO and the international search group coordinated by the Australian Transport Safety Bureau are continuing to research the trajectory prediction problem to refine the required search zone for MH370. A commercial deep-water search company has also been contracted to continue subsurface search operations.