Before the Australian leg of their tour they had been to New Zealand, and played the country's most expensive and premier golf course, Tara Iti.
Greg De Haven and Russell Munsch, both from Texas, have been named as two of the victims.
Quartermain was described as a "champion bloke" and "fine pilot" by those who knew him.
Shortstop Jet Charter senior managing director and chief pilot Mike Falls was one of many to today pay tribute to his colleague.
"We feel the loss of part of the family very deeply. Max was one of the Essendon family, and we're sad and we miss him," Falls said.
Workers at Essendon Airport businesses and several aviation sources described Quartermain as "a great guy ... champion bloke" and an experienced pilot.
The company's website says that Quartermain had an Air Operations Certificate for more than 38 years and an "impeccable safety record".
But he had been involved in at least one "close shave".
On September 3, 2015, Quartermain was the pilot of one of two charter planes carrying a total of 18 people that came within one nautical mile of each other in a frightening close call in bad weather at Mt Hotham.
The two Beechcraft B200 King Airs from separate firms were ferrying Audi customers to an exclusive snow-driving event, from Essendon Airport and from Bankstown Airport in western Sydney, the Herald Sun reported at the time.
Near the destination, Quartermain's plane from Essendon came as close as one nautical mile (1.8km) horizontally and 90m vertically to the Sydney plane. It landed on the runway in the wrong direction, in heavy cloud and poor conditions.
The Sydney pilot said in his report: "If this event did result in a midair collision, two aircraft would have been destroyed and 18 people would have been killed."
The ATSB - which investigated the incident - has been contacted for comment.
