Pushing the Limit

By NAME WITHHELD BY REQUESTDecember 1, 2011

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(Photo Credit: U.S. Army) VIEW ORIGINAL

The mission was simple. Night vision goggle currency sustainment training with some formation flying -- point A to point B and return; two hours of flight time with a takeoff at 7 p.m. Pretty basic stuff for Apache pilots -- no rocket science involved.

Operations had me scheduled as the pilot in command of Chalk 2 and air mission commander for the flight of two Apaches. My backseater was an assistant brigade S-3 scheduled to transfer to our attack unit. He had a lot of flight time but needed this flight to sustain NVG currency. The PC of the lead aircraft was a new instructor pilot, and his backseater was one of the unit's newer pilots. The Chalk 1 pilot needed to complete some readiness level 2 NVG mission tasks and get some NVG time. To evaluate their mission planning capabilities, the Chalk 1 PC and I allowed the two pilots to plan the mission.

After giving the mission planning team a couple of hours, I looked at the proposed route of flight, which would take us over a large lake. Although it wasn't the route of flight I would have chosen, it was OK. There would be no problems with illumination or weather, so one route was probably as good as the other. I glanced at their performance planning card, and it looked good.

We were doing pretty well for crew endurance even though we had to start our 14-hour duty day a little early so we could attend a 9 a.m. safety meeting. We would still have two hours of our duty day remaining when we finished the mission if we took off at 7 p.m. and flew for just two hours. No problem here.

We went to our respective aircraft about 2 p.m. and spent about an hour preflighting. We noted no deficiencies on either aircraft. But where had those clouds come from? The weather forecaster had given us "clear, blue and 22" on the long-range forecast. Oh well, it looked good enough to go. The moon was full and high enough to give us plenty of light, but those clouds might make for a dark night.

To file the flight plan and get weather, we all met in operations. The weather forecast was for light rain, overcast at 1,500 feet and two miles visibility for the entire flight. This weather was a lot different from the previous forecast, but it was still within the unit standing operating procedures requirements and well within the Army Regulation 95-1, Flight Regulations, criteria for operations in uncontrolled airspace.

When we added up the numbers on the risk assessment sheet, it showed the mission as medium risk. How could that be? The weather wasn't that great and the illumination would be reduced because of the weather. Oh well, we had experienced IPs in both aircraft and the mission was fairly simple.

At 6:45 p.m., we cranked the aircraft and everything was going fine. The Chalk 1 pilot had just called ground for clearance to taxi for departure when his engine chip detector light illuminated. The Chalk 1 PC called maintenance while I called operations to advise them of our delay. We shut down both aircraft and waited for maintenance to arrive. When the maintenance crew pulled the chip plug, normal fuzz was all they found. The crew started the aircraft again and rechecked the plug. The light remained out. Once we were released for flight, we realized we'd been delayed almost an hour.

The time was just after 8 p.m. when we finally took off. The ceiling appeared to be lower than forecast, and the winds were beginning to gust, causing us a lot more work as we proceeded on course toward our first destination.

The flight visibility started to deteriorate to below two miles and the ceiling was becoming indistinguishable. I asked the flight lead PC how he was doing. "OK," he said. "The weather will make for some good training."

As we approached a large lake along our route, the visibility decreased to about one mile. Everything might have been acceptable had the route not taken us over the lake. As we crossed the shore, I realized I could not tell how high we were. I called flight lead and told him we were going to pick up additional spacing. He responded with a "Roger" and that we should reach the opposite shore in about two minutes. Suddenly, I couldn't see Chalk 1. I heard the PC transmit, "We're IMC [instrument meteorological conditions], change frequency to approach control!" That was the last we heard from them.

As soon as we lost sight of the lead aircraft, we started a 180-degree right turn while notifying them of our actions. When we completed our turn, we could see lights on the shore. As I looked through the NVG tubes, I could see well enough to remain oriented -- well enough to get back home.

I figured the other crew would be busy, so I waited for them to contact me. After a couple minutes of waiting for a call, I tried to contact them. I tried on all three commo radios and got no response.

Our home base tower heard me on guard and asked if they could be of assistance. I asked tower if they were in contact with the other aircraft. They said they were not but would contact approach control to see if they were in contact with the aircraft. I told them what had happened and that we were returning to the airfield.

It took us about 15 minutes to get back to the airfield. Neither one of us said a word. I was so sure the other guys were OK -- I just knew they were. But they weren't. I kept going over the day's activities in my mind. What could we have done differently that would have saved that crew?

Lessons Learned

First of all, both crews pushed the limit of their crew day. This is a hazard that aviators deal with frequently. The safety meeting was important, but there are usually makeup sessions and the crews could have come in later. Coming in later would have optimized the crews' day.

The maintenance delay pushed the crew day a little further toward the extreme. Did anyone on either of these crews ask questions about how everyone was feeling or if anyone was too tired to fly? Even if the IPs did ask, maybe one of the pilots was tired but chose not to speak up because of a John Wayne image he thought he had to maintain. Even if the control of starting the duty day later had been exercised, additional evaluation of fatigue may have revealed tired crewmembers, causing us to reevaluate our mission.

The crews opted to fly this mission with less than visual flight rules weather. Although the weather was well within AR 95-1 criteria for operations in uncontrolled airspace, was it appropriate weather for initial NVG mission training or for currency sustainment? There may be circumstances when an IP feels a pilot is proficient enough to advance to flying in this kind of weather. If this were the case, a good control would have been to review the local inadvertent IMC procedures and discuss specific crewmembers' responsibilities before takeoff.

When the visibility began to deteriorate below two miles, the AMC asked the Chalk 1 PC how he was doing. He responded that it would be good training. Maybe that would be true with a more experienced crew. However, to operate below two miles of visibility at night, a crew should be in the "run" mode of the crawl-walk-run training cycle. Since this was initial NVG mission training for the pilot in the lead aircraft, maybe a more prudent assessment would have warranted turning around or just landing where they were. The visibility was continuing to deteriorate, and the trend was fairly obvious.

It is possible the hazards in the immediate area (wires, trees and so forth) could have precluded a safe landing and the most prudent decision may have been to return to the base field. A good control for this flight might have included a discussion of mission continuation criteria before takeoff.

There were IPs on board each aircraft in this situation, and that may be considered a control measure. Typically, IPs are conscientious and knowledgeable; however, they are not superhuman. In fact, they may require additional instrument training from time to time. Presenting instruction and evaluating it are significantly different from doing it yourself.

The IP of Chalk 2 indicated that when he looked under the NVG, he couldn't see anything. Why continue aided in that situation? On a very dark night with no light to help them judge distance, an aircrew may have difficulty judging how far they can actually see unaided. I consider it to be a high risk to continue flying under aided visibility criteria when unaided visibility is below minimums. The unit SOP may be the most appropriate place to establish local procedures regarding aided versus unaided visibility.

Cumulative Effect of Minor Hazards

A close look at the events leading up to the accident will most likely reveal hazards aircrews encounter frequently, with only minor variations from mission to mission. Individually, each hazard presented could be assessed as a low risk. However, the cumulative effect of all these hazards significantly increased the overall mission risk.

To be effective, risk management does not end with the mission planning. The process of identifying, assessing and controlling hazards must continue throughout the mission as the situation changes. While in flight, we often must accomplish "hasty" risk management because the particular situation may demand an immediate response. Time may not allow extensive hazard identification and analysis. In these cases, do as much of the process as time will permit. Even a hasty assessment is better than just reacting. The secret lies in our ability to fully integrate risk management into our basic decision-making process.