U.S. Army grounded its aviation units for 24 hours after two AH-64 Apache helicopters collided Thursday in Alaska.

Following two deadly mid-air collisions in the last thirty days, including Thursday's crash of two Apache helicopters in Alaska that killed three soldiers and left another injured, the US Army has ordered a 24-hour safety stand-down of its aviation units next week.

• The tragic collision near Healy, Alaska, occurred as the soldiers of the 1st Attack Battalion, 25th Aviation Regiment, at Fort Wainwright were returning to base from a training mission.
• The unit is part of the 11th Airborne Division, which is nicknamed the “Arctic Angels.”
• Two of the soldiers died at the site of the collision, while the third died on the way to Fairbanks Memorial Hospital. A fourth soldier, who was injured in the crash, arrived at the hospital in time to receive treatment.

It was an alarm for the U.S. Army , as the Apache Helicopters crash followed yet again a deadly March 29 collision of two HH-60 Blackhawk helicopters near Fort Campbell, Kentucky, that killed 9 Army soldiers aboard.

"Army Chief of Staff James McConville today ordered an aviation stand down following two deadly helicopter mishaps that claimed the lives of twelve soldiers," said an Army statement. "The move grounds all Army aviators, except those participating in critical missions, until they complete the required training."

"The safety of our aviators is our top priority, and this stand down is an important step to make certain we are doing everything possible to prevent accidents and protect our personnel," said McConville, himself an Army aviator.

All active-duty units were ordered to put in place a 24-hour stand-down sometime next week. Army National Guard and Reserve units will have until May 31 to carry out their stand-downs.

"During this stand down, we will focus on safety and training protocols to ensure our pilots and crews have the knowledge, training and awareness to safely complete their assigned mission," said McConnville.

The Army said that during the stand-down, the Army "will review the risk approval/risk management process, aviation maintenance training program, aircrew training standardization and management, and supervisory responsibility.

Units will also assess the flight-mission briefing process with an emphasis on risk mitigation, crew selection, flight planning, crew/flight briefings, debriefings and after-action reviews.

The suspension of air operations was effective immediately on Friday, with units grounded until they complete the training , all pilots not involved in critical missions to complete the required training. 

The Army statement announcing the stand down provided the first official mention that the nighttime Blackhawk collision was the result of a mid-air collision.

"While both incidents remain under investigation, there is no indication of any pattern between the two mishaps," read the statement.

Amonh other accidents , Four US Marines were killed during NATO exercises in Norway last year when their V-22B Osprey aircraft went down, possibly after hitting a mountain.

Also, within couple of years , two US Navy pilots were rescued after their T-45C Goshawk jet crashed during a training exercise in a residential neighbourhood near Fort Worth, Texas in the year 2021. However, the pilots safely ejected before the plane went down.