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Flying the Crowded Skies

Flying the Crowded Skies

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CHIEF WARRANT OFFICER 5 TOM MCCLELLAN
Senior Aviator for III Corps and Fort Hood
Fort Hood, Texas


Operating manned and unmanned aircraft in the same airspace is always going to be hazardous, and more so in the future. During my most recent deployment to Kandahar Airfield in Afghanistan, I was notified of a close call of the worst kind — a near mid-air collision between a UH-60 medevac and an MQ-1 Predator unmanned aircraft system. It’s important Army aviators learn from incidents such as this one and share the information so we can reduce the chances of it occurring again.

It was about 2100 hours and five crewmembers were returning to Kandahar Airfield in the medevac aircraft. They were coming from the south and descending from 5,000 feet mean sea level altitude to reach the inbound altitude of 3,800 feet. The procedure called for visual flight rule aircraft to maintain 3,800 feet when crossing the VFR reporting point and continue at that altitude until entering the pattern to land at the airfield.

The crew was unaided, and the CW2 pilot in the left seat on the controls noticed lights ahead. He was unclear if they were ground lights or lights from another aircraft. He mentioned the lights to the other CW2 pilot and they discussed it for a moment.

The medevac would reach the reporting point in about 30 seconds. The pilot on the controls began to feel the lights directly ahead may be lights from another aircraft and started a climb to avoid the traffic. Suddenly, the apparent speed of the lights directly ahead of the Black Hawk increased rapidly. It was another aircraft. One second later, the MQ-1 passed the medevac within 100 feet of the left door at the same altitude, just missing a head-on collision.

In most aircraft accidents, there is a combination of factors that lead to the crash. This was no different. Fortunately, there was not a crash and all crewmembers survived.

What went wrong?

There were many mistakes or events that led to this incident. The aircrew started following the VFR procedures when returning to the airfield, going to the procedural altitude at the VFR reporting point. The aircrew followed the correct radio procedures until the pilot noticed the lights of the aircraft ahead. The medevac then began to climb without contacting the tower. They did not ask air traffic controllers in the tower about the lights.

The near-miss happened about 800 feet above the 3,800-foot inbound procedural altitude. The MQ-1 had departed on a runway heading to the west. Just after takeoff, the aircraft was cleared to turn south and proceed to the bore-site area south of the airfield and climb to the UAS procedural altitude of 10,000 feet.

The radar tracks of both aircraft showed the UAS flew directly over the VFR reporting point — just 500 feet above the VFR reporting point altitude of 3,800 feet. At the point where both aircraft passed each other, the UH-60 and MQ-1 were at an altitude of 4,600 feet, which was about 800 feet above the VFR procedural altitude of 3,800 feet.

This incident illustrated the need to reinforce the procedural control processes with all Army rotary-wing personnel and to establish new unmanned procedures at the airfield. UAS operations now call for all unmanned aircraft to maintain runway heading after takeoff until reaching 10,000 feet before given clearance to turn in any direction, including proceeding directly to the bore-site area. This new UAS procedure will ensure the unmanned aircraft will remain well clear of the vicinity of all VFR reporting points. The lessons learned here are valuable, especially as the density of manned and unmanned traffic around airfields increases in the future.

  • 1 August 2016
  • Author: Army Safety
  • Number of views: 1068
  • Comments: 0
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