About 60 American B-24 planes attacked the Japanese naval base at Hansa Bay on 10 April 1944 – with most departing from the Nadzab air base – today Lae Nadzab Airport.
The events of this day have been in part overshadowed by what American military historians call Black Sunday, which occurred six days later, when the Fifth Air Force lost 37 aircraft to a late-afternoon frontal system which cut them off from their home bases.
It was one of a series of attacks on Hansa Bay, which served as a crucial base and transit station for the Japanese during their invasion of Papua New Guinea during the Second World War.
But for one air crew, it was the last they would ever perform.
According to the US Defense POW/MIA Accounting Agency (DPAA), 12 crew members of a B-24D Liberator died after their plane was shot down as it moved to attack an anti-aircraft site at Hansa Bay.
Four of the crewmen were able to parachute from the aircraft, but are reported to have later died in captivity.
The remains of three crewmen were recovered following World War II by the US Army Graves Registration Service, but the service concluded in 1949 that the remains of another nine were unrecoverable.
That was where the matter rested until 2001, when a US-led team located the wreckage of a B-24D that bore the tail number of the missing aircraft.
After several surveys, US government teams excavated the site and recovered human remains and non-biological material evidence, DPAA said.
Then came a series of tests from the DPAA and the Armed Forces DNA Identification Laboratory (AFDIL) using forensic identification tools which, along with circumstantial evidence, were used to identify the missing men.
As of March 2015, First Lieutenants William D. Bernier and Herbert V. Young Jr, Technical Sergeants Charles L. Johnston and Hugh F. Moore and Staff Sergeants Charles J. Jones and Charles A. Gardner had been accounted for and buried in US cemeteries with full military honours.
The remains of First Lieutenant Bryant E. Poulsen and Staff Sergeant John E. Copeland could not be positively identified, but scientists from DPAA used circumstantial evidence that placed them on the aircraft and accounted for as them as part of the group.
The two men, along with the other crew members, were honoured at a group burial service held at Arlington National Cemetery on 18 March.
In a separate ceremony held on 12 April last year, First Lieutenant Louis Longman was buried after his remains were formally identified through dental records and DNA evidence, which matched a surviving niece.
JPAC said two PNG villagers had turned over the remains which they said were recovered from a wartime crash near their village to a JPAC team in 2005, with further studies carried out in the area from 2007 to 2010.
Lieutenant Longman was the pilot of a P-38J Lightning aircraft that crashed during the events of Black Sunday.