The aircraft was in the on-call status for eight hours when it was finally alerted to start up at 2200. Fifteen minutes later, the aircraft crew was told to shut down and to slide launch time to 2245. During this time the base went into a high state of alert due to suspected enemy penetration of the perimeter defenses. As they waited for launch, the aircrew could hear heavy weapons fire coming from the perimeter.
Finally, the UH-1N was cleared to proceed but was ordered to make two laps around the defensive perimeter to help locate the enemy before continuing on its assigned mission. As the launch commenced, rotor wash created a powdery sand brownout around the aircraft that obscured all ground references. The pilot nosed over two degrees below the horizon and pulled excessive torque (104 percent) initially, then reduced power to 100 percent.
The pilot did not scan the attitude gyro, heading indicator, radar altimeter, turn needle or ball after the initial power pull and attitude setting for the instrument takeoff. The copilot remained fixated on the torque gauge and did not scan the other gauges in order to back up the pilot.
The pilot noticed the aircraft did not break out of the dust cloud in the normal four to five seconds, but neither he nor the copilot recognized that the helo had begun a slow right-hand drift. The crew chief suspected the aircraft was heading to the right but never voiced his concern or let the pilot know he had lost ground reference. The aerial observer also sensed right drift but did not give voice to the concern. Ten seconds after takeoff, the pilot noticed the ball displaced three quarters to the left and immediately corrected with left rudder. The crew chief, located on the right side of the cabin, called "Pull it up, pull it up" as he saw the ground rushing up and the UH-1N in a right wing-down descent.
The pilots then noted the attitude gyro indicating 10 to 15 degrees right wing down and tried to level the aircraft and add power. The corrections were too late, and the right skid impacted the ground with the aircraft heading nearly 90 degrees to the right of the takeoff course. After striking the earth, the aircraft rolled 270 degrees and came to rest on its left side. All crew members survived. The crew chief was thrown from the aircraft as it rolled, while the aerial observer was thrown back into the cabin's center seat and held on. Once all violent motion stopped, he egressed from the cabin. Both pilots unstrapped and exited through the pilot's door. Additional damage occurred when a portion of the UH-1N's blades broke off and ripped through the tail boom of a nearby helicopter. Seconds later a fire erupted, destroying the aircraft.
Grampaw Pettibone says:
Long wait. Wild ride. Lost aircraft.
Ole Gramps is very sympathetic to those who undergo the tedium and hardship of standing by for hours in an on-call status before launching on a mission, especially in the combat zone. But to go forth knowing a brownout takeoff was a sure thing, and not properly scanning the gauges during the execution of same, earns no sympathy. Aircrew coordination took a holiday, probably due to inadequate coverage in the briefing. Both pilots failed to scan properly until it was too late, and the demon of lost situational awareness took hold and dashed the helo to the ground.
When you can't see outside the cockpit, better consult the gauges inside the bird for safety's sake.
Illustrations by Ted Wilbur
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|Title Annotation:||Grampaw Pettibone|
|Publication:||Naval Aviation News|
|Date:||Sep 1, 2004|
|Next Article:||Arizona adventure.|
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