CANBERRA, Australia (AP) — The Australian army will never again fly its fleet of MRH-90 Taipan helicopters following a crash in July that killed four soldiers, the defense minister said Friday.

Australia’s fleet of more than 40 European-designed Taipans has been grounded since July 28 when one crashed into the Pacific Ocean during a nighttime training operation in the Whitsunday Islands off the northeast Australian coast.

Defense Minister Richard Marles told Nine Network television that permanently ending Taipan flying operations was the “only decision that makes sense.”

“We’re making this decision today. In many ways it was inevitable, but it’s an important step to take so that we can get our Black Hawks in the air as quickly as possible,” Marles said, referring to the U.S.-built helicopters that will replace Australia’s Airbus-manufactured fleet.

The government announced plans in January to replace the Taipans with 40 UH-60M Black Hawks. The Taipans’ retirement date of December 2024 would have been 13 years earlier than Australia had initially planned.

The government made the decision now to stop flying the Taipans because one of the four investigations into the crash will take another 12 months, Marles said. After the cause of the crash is explained and any faults in the Taipan fleet are rectified, that would have left only a few weeks for them to fly before they were retired, he said.

Since the January announcement, the Taipan fleet was grounded in March after a helicopter ditched off the southeast Australian coast during a nighttime counterterrorism training exercise. All 10 passengers and crew members were rescued.

The first three of Australia’s Sikorsky Aircraft-manufactured Black Hawks were delivered this month.

“There are going to be challenges around a capability gap here, and that’s why we are working with our international partners, particularly the United States, particularly to get more time for air crew to train so that they can be certified on the Black Hawks as quickly as possible,” Marles said.

The Australian army will also begin flying new Boeing AH-64E Apache helicopters from 2025.

The Australian Defense Force will continue to fly the Black Hawks’ navy variant, MH-60R Seahawks, as well as Eurocopter Tigers and Boeing CH-47F Chinooks.