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Know Your Limits

Know Your Limits

F Company, 1st Battalion,
171st General Support Aviation Battalion
Mississippi Army National Guard
Jackson, Mississippi

Do you understand and apply the power limitations of your helicopter? No matter which airframe you fly or your experience level, you should always understand how and why your helicopter performs like it does.

It was 2012 and I was deployed to Afghanistan Regional Command-East, flying medevac. I had been out of flight school for about nine months before arriving at Fort Hood, Texas, for mobilization. During this time with the unit, I trained at the High-Altitude Army Aviation Training Site in Gypsum, Colorado, and flew as much as possible, which put me at about the 300-hour mark when the unit arrived in Afghanistan. What did I know? Absolutely nothing.

We had been in country for several months and were well versed in the battle rhythm. We were flying med-on-med chase, which means both aircraft were medevac helicopters. Our 48-hour rotation started with a 24-hour shift as Chalk 2, meaning we were secondary for point-of-injury/primary for patient transfer, and it ended as Chalk 1, the primary aircraft to respond to calls for assistance.

During one rotation, I was the pilot while the pilot in command was the company executive officer who was an instructor pilot and instrument examiner. The PC, in my opinion, was an extremely good pilot. On our second day of the rotation, we were Chalk 1, and I felt we were ready to go if called.

You always hope for a slow rotation, but that was not the case on this day. We received an urgent 9-line message (request for medical evacuation) that evening along with the weather update and launch approval. As soon as the 9-line started to drop, we were sprinting to the helicopter. Within minutes of the initial call, we were pulling pitch as a flight of two for the POI. I remember thinking it was a dark night, but that was typical in Afghanistan in red illumination.

Although the flight was short, we were able to discuss winds and power requirements. Winds were calm, max torque was in the low 90s and power requirements were standard for the conditions. We identified the POI and set up for the landing. The PC was on the flight controls while I was navigating and talking on the radios. He picked a spot to land the aircraft and began the approach. The dust cloud began to form higher than anticipated and our crewmembers called out the dust cloud’s status, “Cloud forming, cloud tail, cloud cabin.” We were totally engulfed in dust, but we weren’t on the ground, hovering with zero visual references. Finally, I saw the ground and noticed we were drifting left, so I announced, “Drifting left.”

The PC then applied right cyclic, the crew chief announced, “Sliding right,” and the PC called a go-around. That is perfect, except we were still in the dust and he initiated the go-around with an excessive amount of collective. As we cleared the top of the dust cloud, which had grown to about 80 feet above ground level, the low-rotor horn came on. Torque was about 105 percent, the rotor was in the low 90s and we were sliding back and right. All I could think was, “Lower the collective, forward cyclic.” I don’t know if I said this out loud or just in my head, but that was the exact input the PC made.

We were able to gain forward airspeed and fly out of a bad situation. We made a modified pattern and performed another approach to an area clear of the lingering dust cloud. This time, he landed the aircraft, we picked up our patient and then headed to the forward operating base.

Earlier, I asked if you understood the power limitations of your helicopter. We understood the requirements and limitations, yet five seconds into a bad situation we were not thinking about aircraft performance. What I learned from this incident is to apply the performance criteria of your aircraft for every takeoff and landing.

  • 1 February 2015
  • Author: Army Safety
  • Number of views: 10220
  • Comments: 0