Racing the sun.
Life on the boat isn't all that bad, in fact, we'd enjoyed nearly a full week of liberty in Singapore just two weeks earlier. The food is good, and we have ready access to fitness facilities. However, you can only float for so long before craving a change of scenery. However, as anyone who has deployed as part of a MEU can attest, a change of scenery sometimes comes unexpectedly and can bring a marked decrease in your quality of life.
Two months out from the surf, sand and all things San Diego, we found ourselves floating off the coast of Djibouti in the Horn of Africa (HOA). With fish tacos clearly worlds away, what we found instead were "fish boxes": invisible boxes found only on oceanographic charts. Within these fish boxes, we would turn untold numbers of "gator squares," all the while endeavoring to maintain flight currency and support training ashore. We eagerly anticipated real world tasking.
With flight currency and proficiency as our mandate, we launched as Dash 2 in a division of four CH-46Es. We were heading feet dry to conduct section terrain flight (TERF) and division confined-area landings (CALS) in Djibouti. After that, we were to shut down and assume the role of casualty-evacuation (CasEvac) standby in support of battalion landing-team (BLT) training at resupply point-1 (RSP-1). Our basic maneuver had us make a single hit at RSP-1 to resupply and fulfill the Marine logistics (MarLog) portion of our tasking before commencing training.
With the MarLog complete, we stopped at Djibouti International airport to take on fuel. With tanks full, we set off to the TERF route as a section. Two hours later, we pushed out to the CAL site, where the other section joined us on deck. We conducted division CALS in each position before dissolving the flight and pushing back to Djibouti International to refuel.
With sunset rapidly approaching, we departed for the short return flight to RSP-1. We would shut down there and spend our first night away from the boat--a perfect end to a full and successful day of training.
RSP-1 sits at a intersection in a small valley, where the BLT could easily stage and transit to their range complexes and back. Our aircraft would be established as the on-call CasEvac section during all live-fire events. The approach to landing is made on an east-west or west-east heading, because of high ground on both the north and south sides of the zone. The zone is large, flat and full of 12-to-18-inch volcanic-type rocks. We were not the first MEU to use this zone, so we knew there was adequate space for multiple aircraft. Several large areas inside the LZ had been cleared of rocks for aircraft and marked as landing points.
What happened on our final approach to freedom? We were in the Dash 2 position on final approach to RSP-1 with decreasing airspeed and altitude. I already had conducted landing checks--from memory, not the checklist--and we were approaching short final with our landing profile established. At 200 feet, I began to call airspeed and altitude at regular intervals. The pilot initiated control inputs and said we were taking separation from lead to avoid rotor turbulence.
Recognizing the intended point of landing, I called out 100 feet and shifted my weight in preparation to assume the controls if I needed to. As I was about to call out 50 feet, the aircraft unexpectedly made a rapid rate of descent, and the pilot responded with all the collective he could pull. With torque horns blaring, he squeaked out just enough collective to silence the horns.
The aircraft didn't have the juice to maintain our profile, and we touched down well short of the intended point of landing. Our ramp struck a small boulder, which drove the ramp actuators upward, breaking them off the airframe. The impact also damaged the utility hydraulic and electrical systems, as well as the airframe.
How is it that we could fly all day, only to fall prey to blow it in the final few seconds of the flight? We had conducted thorough flight and cockpit briefs. We delineated responsibilities and religiously executed them. We flew all day according to the parameters briefed. I knew exactly what to expect from the crew and they from me. This was supposed to be just another landing, no different than the others. What had gone wrong?
THE PRECAUTIONS for such events have been with me since the summer following my sophomore year, when I flew a small Piper airplane virtually everywhere I went. I remember my flight instructor telling me, "Manage the variables and always put controls in place." He added, "Those things you can't control will eventually manifest themselves and it'll usually happen at the worst possible moment."
"A pilot," he would say, "can always handle one unforeseen variable, and usually two, but a third unchecked variable will almost certainly take you down."
What variables collectively led to our hard landing that fateful day in Djibouti? As much as I'd like to blame Friday the 13th and the boat's brilliant air-plan cartoon, the reality is that we had allowed a time crunch to dictate the conduct of our final 10 minutes of flight. With the sun rapidly descending, and as our crew day began to run short, we departed in earnest to reach our final destination. Flight-planning considerations, the basis for such success throughout the day, were no match for our race with the sun.
In our haste, we allowed ourselves to deviate from the plan and break from the brief. The landing checklist I had completed from memory did not include the variables that any pilot (and certainly a pilot of a 46-year-old helicopter) should always pay particular attention to: wind direction and velocity. We accepted a landing with a tailwind. The tailwind had not affected our lead aircraft as far as we could tell, but not all aircraft perform exactly the same, and in our case, aircraft 04 is one of our less powerful players. What may have been a minor detail to our lead aircraft was for us the straw (tailwind variable) that broke the camel's back (in this case, the Phrog's ramp).
In our rush to arrive at the LZ and begin our overnight camping experience ashore, we ignored the weight of the aircraft (recently refueled and with passengers aboard) and the direction of the wind. We had decided the threat was such that the ramp would be left in the horizontal position to support the tail gun.
We also had not briefed the physics of flying aircraft that are routinely on the edge of their operating envelopes. By setting up our landing profile with a tailwind, we had positioned the aircraft such that power required was nearly equal to power available. Given this, the reaction to the torque horns induced a rate of descent from which the power required had exceeded the power available. In the interest of preventing an overtorque, we had created a situation where we guaranteed an overtorque to arrest the rate of descent. So, we landed short of our intended point of landing and damaged the aircraft.
What should have changed? We had just left Djibouti International and had been given the wind direction and velocity to us over the radio. It is a safe assumption that the reported winds would be the same 25 miles away inside channelizing terrain. Once identified, a reminder to the lead aircraft would have been appropriate, and he would have changed his landing direction. Also, we overestimated the enemy threat and should have raised the ramp, acknowledging that we wouldn't need the tail gun on final approach to landing. We should have conducted our landing checks using the checklist.
We should have spent some time briefing our power margins. This would have increased our awareness of the different phases of flight, where we would be power limited and where we would have excess power.
Maj. Kill flies with HMM-268 (REIN).
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|Title Annotation:||wind direction and velocity|
|Author:||Kill, Bryan L.|
|Date:||Nov 1, 2012|
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