In mid-1955, Arnold’s unit at Foster switched to flying the newer F-100, which was much sleeker and faster than the chubby-looking F-86. Arnold had already fallen in love with the F-100 in January, when he saw one during a visit to Eglin AFB in Florida. Much bigger than the F-86, he thought it “sort of mean and ugly-looking.” Although he couldn’t wait to fly one, the F-100 was grounded at the time to fix severe problems with the control system.
Despite the problems, however, North American had already started delivering F-100s to George AFB in California and by July 1955, the planes began appearing at Foster. Since Arnold was an assistant maintenance officer, he was one of the earliest pilots to check out in the F-100. He came close to crashing on his first flight in August 1955. Using the procedure the instructor had taught him, as soon as he took off the airplane began a pilot induced oscillation – a wild series of climbs and dives like a porpoise.
Although the term “pilot induced oscillation” makes it sound like it’s the pilot’s fault, it’s not. Instead, the control system in the airplane has a problem so that whenever the pilot tries to fly the airplane, it begins to oscillate. The only way to stop it is for the pilot to let go of the stick or freeze it in one position. Some oscillations are benign – even the Wright Flyer had a mild one – but some can tear an airplane apart and kill the pilot. An oscillation on takeoff or landing is especially dangerous because of the increased chance of slamming back into the ground.
Fortunately, after several cycles of almost crashing into the ground, Arnold realized what was happening. He relaxed the pressure he held on the stick at the top of the next cycle and the airplane smoothed out. Several other pilots had similar experiences on their first takeoffs, some of them even banging onto the runway again after lifting off. The F-100 pilots quickly reverted to using the same takeoff procedure they had used in the F-86 and the wild rides ceased.
Another distinct F-100 feature was due to the afterburning engine the airplane used to break the sound barrier in level flight. Unlike later afterburners that lit in stages, the F-100’s afterburning engine was an all-or-nothing affair that delivered a jolt to the pilots as it lit. An F-100 taking off had a distinctive sound not heard before. The engine first screeched like a banshee as it spooled up to full military power. As the pilot moved the throttle to maximum power to light the afterburner, the screeching stopped for a fraction of a second. The afterburner then kicked in with a thud followed by roar as it propelled the airplane down the runway and into the air. A flight of four F-100s taking off left anyone near the runway unable to hear for several minutes until the noise faded into a low rumble as the airplanes disappeared on the horizon.
I remember hearing this noise many times as a kid, and even though I haven’t heard an F-100 in probably 30 years, I think I would still recognize it!