Minor set back. In aviation, it is a good idea to shake things out well before a long trip. With all new components, it is important to work them over to make sure one gets over the infant mortality phase, albeit safely…..
Last week, got ready to depart Birmingham area for a site visit. Started up the engine, it sounded rough. Taxied around, still sounded rough, did a complete run up, still rough. Lined up on the centerline of the runway, full power – still rough. At rotation speed (just prior to take off), pulled the throttle and aborted take-off as the engine did not “sound” right. Taxied over to the mechanics hangar and called him on the phone to come out and “listen” to the engine. As I pulled the throttle, it came out in my hand. Showed it to my mechanic, who had a few choice words from the A&P’s extensive dictionary of terms. This was a new throttle cable that had been replaced less than 50 hours ago…..in aviation terms, this is called “INFANT MORTALITY”. So, this begs the question, what else do I need to shake out and make it fail now instead of failing over the Atlantic or the Pacific.
Considering this failure in various phases of flight, if the throttle had failed when I was at full power, I would have had to get up to pattern altitude, shut down the engine and glide in. If it had happened in cruise, I would have had to get to an airport and shut down the engine and glide to a landing. The worst outcome would have been if it had failed while landing. In a way this was a good exercise in how to handle an emergency, one that did not happen because the engine did not “sound” right !
The engine did not sound right because upon investigation we found out that the plug in the #3 cylinder had carbon deposit on it. I could have cleared it up with some aggressive leaning, but I decided to abort the mission rather than take a bird in the air with a known/doubtful issue….. as the saying goes…. there old pilots or there are bold pilots, there are no old-bold pilots….