Too Quiet, Part 2 - Your Other Left

Cauliflower in Souk, Fez, Morocco - photo by JoAnn Sturman

by Steven R. Oberst

It was over 4 years and 1,800 flying hours later before I experienced another engine failure. The flight was a support mission taking ten Air Force security police (SP) to a missile site undergoing maintenance. On the flight were nine SPs riding in the passenger compartment, which was all the aircraft could accommodate. This was a single pilot mission, so the lead SP NCO, SSgt Reed, was seated in the co-pilot’s left seat position.
I completed my flight planning and noted that the power margin for takeoff would be slim. With ten fully equipped SPs and a warm day, power available would be adequate, but the takeoff would require some finesse. My technique in this type of situation was to bring the helicopter to a hover then gently move it forward, maintaining close proximity to the ground during the initial part of the takeoff maneuver. This is called maintaining “ground effect” and results in increased rotor blade efficiency, which in turn reduces engine power required for takeoff.
All seemed normal with the helicopter as I hovered out to the helipad for takeoff. I gently nudged the cyclic, the primary flight control stick, forward and slowly began to accelerate without using any additional power. I achieved translational lift without adding any power. (As a helicopter moves forward, about 15-20 knots in the UH-1 Huey, the helicopter achieves “translational lift”, a state which provides extra lift for takeoff.) At about 50 feet above the ground and approaching 60 knots I felt comfortable enough to increase power slightly. As soon as I raised the collective I heard a loud bang.
Reacting instinctively I immediately lowered the collective and looked at the gauges. Sure enough, the engine had failed, and the sudden quiet was memorable. When the mishap happened, I was flying over a flat grassy area between the main runway and a taxiway - perfect terrain for a forced landing. While keeping the nose straight, I elected to use a series of short flares with the cyclic instead of the continuous flare used in a normal autorotation. This technique allowed me to avoid striking the ground with the tail rotor, since the helicopter’s nose up attitude necessarily placed the tail close to danger. The aircraft gross weight was near maximum, but the flat, grassy surface beneath would permit me to keep the airspeed at higher than normal, so we would not fall like a rock from 30 feet in the final stages of the autorotation. Immediately before touchdown with an airspeed of 25 knots, I leveled the helicopter and pulled up on the collective to slow our descent. The helicopter skids touched down and we slid about a 100 feet.
The time from engine failure to coming to a stop on the ground was probably less than 15 seconds. I remember how quiet it got when the engine stopped and how everything seemed to slow down as I maneuvered through those 50 feet to the ground. It happened so fast that by the time the SPs in the back realized what had happened, we were safely down. However, SSgt Reed who was seated in the front seat, had an entirely different view of things. “Captain,” he said afterward, “that scared the shit out of me, but nice job!”
The previous day our engine mechanic, A1C Potts, made an improper adjustment of the fuel control which resulted in a compressor stall (the loud bang I heard) and the engine failure. Airman Potts apparently turned the control clockwise instead of counterclockwise and then failed to properly document the aircraft forms. This meant the change was never signed off by a maintenance supervisor, and I had no knowledge of the maintenance work completed. Potts was given a written reprimand and placed back in a training status.
This time it was my smiling face in the MAC Flyer, but another bonus came a few weeks later. Driving across the base, I was caught by an SP on radar. I looked at my speedometer just before I pulled over. “Damn,” I thought, “37 in a 25 means a ticket for sure.” The SP came up to my door and was about to ask for license and registration when he recognized me. “Hi, Captain,” he said with a grin, “try to keep the speed down a little, Sir. See you later.” It was SSgt Reed.

Thai Pilot, How High Can You Climb?

Zebras Serengeti Plains, Tanzania - Photo by JoAnn Sturman

Scott Sturman

Sky Pilot, Sky Pilot
How high can you fly?
You'll never, never, never reach the sky.
------Eric Burdon and the Animals

I was one of thousands of helicopter pilots the United States Army trained during the Vietnam War era.  In addition to American students, trainees included pilots from foreign countries including Iran, Saudi Arabia, Jordan, Thailand, and South Vietnam.  My class consisted of twenty U.S. Army officers, ten Air Force second lieutenants, and four lieutenants from the Royal Thai Army.

The first 4 ½ months of flight training were conducted at Fort Wolters in west Texas near Mineral Wells. All new students flew the TH-55, a peppy trainer powered by a four cylinder super charged engine. The aircraft held two pilots who were encased in a Plexiglas bubble which allowed for excellent visibility. It was a simple, dependable machine and fun to fly.

The ground around Ft. Wolters resembled the meteor pocked surface of the moon due to divots from crashed helicopters at the hands of inexperienced pilots who paid a hefty price for poor airmanship.  Most of the fatalities were foreign students who entered flight school directly from their home country and were limited by a language barrier and lack of exposure to operating machinery. Whereas most American officers began driving automobiles at 15 years of age, it was not uncommon for foreign officers to struggle driving a car.  (For two humorous stories on this subject see S.R. Oberst's Major Wrongway and Major Potty Break) 

After ten hours of flight instruction with an instructor pilot, a student was expected to solo. This entailed flying a simple traffic pattern with a take off and landing at the main airfield. The U.S. Army had little patience with those unable to meet these requirements.  If the student had difficulty and did not solo within a designated time frame, he was washed out of flight school. Ironically, if a marginal student successfully soloed, he could continue in flight school with few restrictions–a good reason for the cratered west Texas landscape .

Helicopters have four basic flight controls:

The cyclic or “stick” which is held in the right hand and controls the plane of the spinning main rotor. It allows the aircraft to move forward, backward, right, or left.

The collective is held in the left hand and is moved up or down to change the pitch or angle of attack of the main rotor blades. Lifting the collective increases the pitch which equates to more power and torque, which allows the aircraft to climb or accelerate.

The rudders adjust the pitch of the tail rotor which compensates for changes is torque when the collective is either raised or lowered. The rudders are controlled by the pilot's legs. When the collective is raised, the nose of the aircraft will yaw to the right, so the pilot must press the left pedal to keep the nose straight. The converse is true when the collective is lowered.

The throttle is located on the collective and is twisted manually to change the RPM of the engine. The main rotor will tend to slow when the collective is raised unless the throttle is increased but will spin too rapidly if the throttled is not decreased when lowering the collective.

Manipulating these controls simultaneously with both arms, both feet, and the left wrist requires a certain degree of coordination. This is particularly the case during landings when the controls are changed constantly over short time intervals. Normally as the helicopter descends toward the landing site very little power is needed, but immediately before touch down the collective must be raised to slow the rate of descent while the left pedal is depressed to keep the helicopter from spinning rapidly to the right.

Of the Thai flight students, 2nd Lt. Arak was the favorite of the class.  He spoke halting English but socialized comfortably with the other officers in the class.  Every Friday night Lt. Dan Summers, an Army National Guard student, taught the affable Arak and most of us bachelors in the class to drink scotch at the Officers' Club. Yet for all of Arak's popularity and social skills, he was slow to gasp the essentials of piloting a helicopter.

Arak's ten hours of flying time elapsed without a recommendation for a solo flight. He was at the stage when it was either solo or wash out, which meant a quick trip back to Thailand to serve in the infantry rather than a later tour as a prestigious helicopter pilot. Most foreign students would rather crash and burn than fail, so Arak persuaded his instructor to give him a chance.

The head of our class's flight instruction program was a Department of the Army civilian who went by both of his first names, Joe Bob. He was perhaps fifty years old, well over six feet tall, and weighed 260 pounds with a flat top and a penchant for bluntness.  His hobby was carving bizarre looking male wooden figurines with enormous penises and selling them to the students.

Joe Bob perched himself in the control tower so he could view Arak's solo flight first hand.  The lift off to hover, take off, and traffic pattern went well.  A reasonable landing would seal the deal. As Arak neared the ground on final approach, he lifted the collective to slow his descent, but rather than push the left pedal to keep the nose straight, be pushed the right. The helicopter was less than twenty feet above the ground and began to spin clockwise. Arak, frightened to be in a spinning helicopter so close to the ground, panicked and pulled the collective up to his armpit and pushed the right pedal to the floor.  Spinning like a top, the chopper cork screwed 2000 feet straight up above the air field.  All the other pilots monitoring the radio heard Joe Bob screaming, “Arak, you sorry son of a bitch! Left pedal! Left pedal! If you don't get your shit together, you're gonna die!”

To his credit Arak decided it was best to avoid a certain death in a helicopter crash and take his chances with Joe Bob on the ground. Once he stopped the spin and regained his composure, Joe Bob talked him down like a grandfather reading a story to his favorite grandson. Arak landed without incident and staggered out of the cockpit, where Joe Bob was there to greet him.  “You scared the hell out of me, Arak. For a while it looked like you were flyin' up to meet your maker.  There will be plenty of time for that later when the Viet Cong take a few shots at you.”