The Australian Transport Safety Bureau's (ATSB) final report into Malaysia Airlines flight MH370 calls for flight tracking that is even more precise than the 15-minute position tracking interval called for by ICAO.
The 440-page report details the history of the missing Boeing 777-200ER, from its takeoff on 8 March 2014 on a Kuala Lumpur-Beijing flight, to its disappearance and subsequent search efforts near Malaysia, and later in the southern Indian Ocean.
After three years, the search for the missing aircraft, which vanished with 239 onboard, formally ended on 17 January 2017.
"While there has been significant enhancements in the tracking of commercial aircraft in recent years there are some limitations to the improvements," says ATSB. "The ICAO mandated 15-minute position tracking interval for existing aircraft may not reduce a potential search area enough to ensure that survivors and wreckage are located within a reasonable timeframe."
It calls on the aerospace industry and operators to explore ways of providing rapid, possibly automatic, tracking of an aircraft's position globally, both in existing and future fleets.
"[The ATSB recommends] that states ensure that sufficient mechanisms are in place to ensure a rapid detection of, and appropriate response to, the loss of aircraft position or contact throughout all areas of operation."
The ATSB also notes that ICAO Annex 13 offers no guidelines for the inclusion of information for some aircraft searches in accident investigation reports. Annex 12 does not require that search information be published or analysed.
"This limits the ability for research to determine the factors that help or hinder a search."
The ATSB adds that the underwater search for the aircraft, as of 30 June 2017, came to A$198 million ($155 million). Of this, the underwater search cost A$170 million, bathymetry A$20 million, programme management A$7 million, and other items A$1 million.
Of this $198 million, Malaysia bore 58% of the cost, Australia 32%, and China 10%.
"The reasons for the loss of MH370 cannot be established with certainty until the aircraft is found," says the Bureau. "It is almost inconceivable and certainly societally unacceptable in the modern aviation era with 10 million passengers boarding commercial aircraft every day, for a large commercial aircraft to be missing and for the world not to know with certainty what became of the aircraft and those on board."
It adds, however, that the search has sharply reduced the number of high probability areas where the aircraft could be.
"The understanding of where MH370 may be located is better now than it has ever been," it says. "The underwater search has eliminated most of the high probability areas yielded by reconstructing the aircraft’s flight path and the debris drift studies conducted in the past 12 months have identified the most likely area with increasing precision. Re-analysis of satellite imagery taken on 23 March 2014 in an area close to the 7th arc has identified a range of objects which may be MH370 debris."
This suggests an area of less than 25,000km² that has the "highest likelihood of containing MH370."