Page 27 - July 2015 Volume 9, Number 7

As the sun retreated and daylight slowly dissolved into darkness, Davis prepared to take the first of many nighttime observations of the stars. Using a celestial sextant, he carefully held the instrument in a level position before taking a reading on a reference star. He would repeat the reading a number of times for accuracy, always checking to be certain the sextant was level (a bubble, similar to that used in a carpenter’s level, was an integral part of the device and was illuminated by a battery). The average reading of a star’s height and its bearing from the airplane gave Davis the Woolaroc’s approximate position above the earth’s surface. Taking the readings was easy when the air was calm, but in turbulence or if the observer was buffeted by the slipstream, the procedure was more difficult. Because Davis was located far behind the cockpit and isolated from Goebel by the extra fuel tanks, the two men devised a string and pulley telegraph system to communicate throughout the flight. Based on the observations taken with the sextant, Davis would write down the information and suggest new compass headings to remain as close as possible to the pre-planned course.
To help him guide the Woolaroc toward Hawaii, Davis referred to the Great Circle route he laid out for the flight. Great Circle routes were commonly used for long- distance flying, particularly over a large expanse of water such as the Pacific Ocean (Lindbergh had used a Great
Circle route for his flight to Paris). Initially, Goebel flew a heading of 250 degrees. As the hours passed during the night, Davis telegraphed Goebel minor changes in heading. The Woolaroc’s pilot occasionally disagreed with his navigator, but better judgment prevailed and Art dutifully complied with the course changes.
Another concern throughout the flight was the effect of the upper winds on the airplane’s position. Winds aloft could easily blow the airplane off course, particularly during the night hours when Davis had no way to observe the waves below. Any deviation of the monoplane’s path across the earth’s surface could adversely affect accurate navigation. To help compensate for the wind, white stripes had been painted across the airplane’s horizontal stabilizer and elevators at various angles such as 10-, 20-, 30- and 45-degrees.
Fatigue was another adversary. Goebel and Davis both fought to stay awake as the Woolaroc droned its way across the ocean at an average speed of 93 mph. As the monoplane cruised along, Goebel appreciated the fact that the only thing keeping him from an unwanted swim in the cold Pacific was the reassuring roar of the nine-cylinder Wright radial engine (all eight of the contestants that day were flying behind a Wright “Whirlwind” engine and were counting on its rugged reliability to keep them in the air). As a result, Art kept a constant vigil on the powerplant’s vital signs, and after
JULY 2015
KING AIR MAGAZINE • 25