Our instructor hit the start button, the igniters started ticking in my headset, and then the powerful fumes of unburned kerosene started to fill the cabin. I looked frantically about as the overwhelming strength of the fumes had me sure something was horribly wrong.
“We have a bit of a tailwind. That is why we have a little bit of a smell in the cabin.” The instructor said calmly over the radio.
Little bit! It smelled like I crawled into the fuel tanks and was taking a damn bath in the stuff.
The engine started to fire and I could hear the turbine spinning up. As the RPM came up, the rotor started to turn. Cool, I thought, the fan is starting, and it will blow away the heat and noxious fumes.
The rotor blades on a Huey are massive. I don’t recall the exact dimensions, or how much they weigh. But they are big. And they have these little tabs on the outer trailing edge that help balances them. Because if they are not balanced, then you get this one to one vibration that is annoying at full RPM, but nauseating at lower RPMs. Like when the rotor is first cranking up.
So, here I sit, overwhelmed with the smell of kerosene, my stomach is starting to turn because of the heat and fumes. Then this bounce starts in. It was not a vibration. The aircraft bounced once for every slow rotation of the rotor blade. As the rotor blade sped up, so did the bounce. Again, it was a bounce, not a vibration. I was quickly becoming more nauseated in an aircraft than I had ever been before.
Wump………wump……..wump……wump….wump…wump..wump, wump, wump…
And then, as the rotor came up to flight RPM, it washed away the fumes and the bounced softened to steady, barely noticeable vibration. The instructor was initially concerned about the severity of the vibration, and thought we were going to have to shut down. But as it smoothed out, he told us what happened. The morning flight must have put the blades a little out of balance, but didn’t write it up in the maintenance log.
He noted it right then so we didn’t make the same mistake.
From the moment the instructor hit the start button, until the blades were spinning fast enough to smooth out the bounce was probably less than a minute. But it was a long, miserable minute that had me thinking I made a terrible mistake.
But after that minute, the only terrible mistake I made when it came to flight school, was throwing it all away.