What Would You Do?
June 28, 2012
I took the controls, or at least the cyclic, and nosed the aircraft toward the ground to clear the barely visible set of wires. Simultaneously, I lowered the thrust control lever in an effort to dive/drop the aft rotor system under the wires. Ahead, the narrow valley we were following made an almost 90-degree right turn followed immediately by a sharp left turn.
We were within three miles of our intended helicopter landing zone and there were still several more aircraft, three to five minutes behind our position, intending to use the same valley for their infiltration. Nosing the cyclic forward toward the ground assisted our clearing the wires with the forward rotor head. However, I wasn't as certain about the aft rotor head.
In case you're wondering, the aircraft we were flying was a Chinook. So what would you have done if you were in my cockpit -- besides asking yourself, "Where did those wires come from?" or "How come we were not told or warned of those wires?"
There is nothing taught in flight school that can prepare us for this situation. Of course, we did all of the preflight preparations such as reviewing maps and imagery, both digital and paper. We can always recall "all roads have wires" -- only there was no road in this valley. We also had no chart update manual map available that depicted those wires.
There I was, flying in a dark valley with 28 passengers and a crew of seven, wondering if we had hit those wires. We were within three miles of our HLZ and a 20-minute flight from the nearest forward operating base. I thought, "Do I reference my technical manual or my -10 checklist with a condensed version of the emergency procedures?" Recalling the underlined steps of an emergency procedure or asking the crew to help me with the -10 checklist would not have helped. The Chinook is not equipped with a wire strike protection system and there are no emergency procedures for a suspected or actual wire strike. Still, we know that regardless of the aircraft size, wires and power lines pose a serious threat to the safety of our crew and aircraft. Therefore, as we rapidly approached the sharp right turn, we were still not confident our aft rotor system could actually clear the wires safely. Given that situation, what would you do?
I chose to land immediately to verify if the aircraft was still airworthy. This was important before I committed the passengers, crew and myself any deeper into the valley beyond the point of no return with a broken aircraft on the verge of coming apart.
There are many accidents involving aircraft hitting wires. We must have the vigilance, maturity and a desire to arrive alive and fight another day. After all, an assault aviator's portion of the mission is just that, a portion of the overall mission. Jeopardizing the passengers and crew with continued flight without ensuring the airworthiness of the aircraft would not have been prudent.
What are we expecting to find once we've landed? What are we looking for to confirm or deny the wire strike? What do we do if we find damage? These are all valid questions. Those thoughts probably crossed my crew's mind, but the decision to immediately land was so fast that it wasn't until afterward that I was able to explain to the crew what just happened.
When we were safely on the ground with little to no moon and/or celestial light, I asked the crew to inspect the aircraft for a suspected wire strike. I instructed them to look for wire wrapped around the aft head or possibly visible pieces of the aft rotor head out of place because the wire either severed or sheared it. My biggest concern was the aircraft had not exhibited any unusual flight characteristics during the 20- to 30-second flight after the suspected strike. I feared it was just a matter of time before a portion of the aft rotor came apart, making continued flight impossible.
I instructed the crew to use their white lights and inspect the aft rotor head, paying particular attention to the aft pylon area, blades and rotor head. Following a quick but thorough look, we found no visible damage and discussed our next course of action. I decided to conduct a final verification. Although I was confident the aircraft was capable of flight, I wanted to pick it up to a hover, thereby loading the aft head and moving the flight controls similarly to a flight controls check conducted as part of a hover check per Chapter 8 of the -10. This check was to verify the aircraft's airworthiness -- the theory being that if something should fail during the hover check, our chances of survival were far greater falling from 5 to 10 feet to the ground than if we were to proceed to the HLZ at 60 to 80 knots and 150 to 300 feet AGL.
I picked up the aircraft to approximately 8 feet and conducted a quick flight controls check. Now more confident that the aircraft was functioning normally, I transferred the controls and we proceeded to the HLZ. Following our infiltration, we returned to our home station/base and shut down the aircraft. With the sun coming up, we inspected the aircraft and noted the forward rotor head had cleared the wires, but there was a scratch found on the aft pylon, No. 1 engine side, which was suspected to have been caused by the wires rubbing along the aft pylon below the level of the rotor system. No repairs or maintenance were required.
Despite the fact the operator's manual does not tell us what to do in the event of a suspected wire strike during a stateside aircrew training manual flight, I believe most aviators would have immediately landed, shutdown and gone over the aircraft with a fine-tooth comb. However, this suspected wire strike was while conducting a combat mission.
What would you have done? Would you have continued to the HLZ? Would you have turned around and flown to the nearest FOB more than 20 minutes away? Or, would you have landed and inspected the aircraft with it running like we did or would you have shut down the aircraft while in a combat zone? We can simulate and discuss a myriad of emergency procedures and unanticipated events that could occur during a flight, but do we really ever ask ourselves what we would do in a similar situation?