Trouble shooting in Bisbee, AZ

 Wednesday, June 21

This morning, Pierre Louis and I sat down and he gave me a step-by-step tutorial of how to fly out of the Sierra Vista Airport. There is some civilian air traffic, but 90+ % is military - and it's a VERY busy airport, since now it's fire season. There's a fire at Mt. Lemon and so fire fighting planes are also using this airport.  I was really grateful for his advice, since I have so little experience talking with a tower it could almost be considered no experience.

Happily, the tower folks were friendly and very patient with us. We were a flight of two, and I led the way to Juliet taxiway, turned left, then turned right at Golf taxiway, and held short at Rwy. 26 - which is over 10,000' long. And held short, and held short, and held short... Watching all the different types of military planes take off and land, watching a wasp-waisted drone that was over twice as big as my Aeroprakt - it was really interesting and helped keep my mind off the sweltering heat in the plane. 

I waited 14 minutes at the hold short line before I was given clearance to depart and I heard ATC give clearance to Dennis just as I was taking off. We were headed back to Bisbee, to take the copper mine tour. But darn, darn, darn - as I climbed to 7800', there was that annoying knock again. Only twice, but I decided to fly at 7500' and take a slightly longer way to Bisbee Municipal Airport via a valley, instead of climbing to 8000' or 8500' and going over the mountains.

We landed without difficulty and Eric Swisher with Copper City Aviation flight school was there. We discussed my knocking issue again and he agreed to do some trouble shooting. So Dennis borrowed the courtesy car and went to Bisbee to take the mine tour and I stayed at the airport. Eric put in a new fuel pump (although that wasn't the problem, but he had one available and mine was seven years old and due to be replaced.) Eric said there was definitely no mechanical problem, and said it might be fuel vaporization since my engine has a long fuel line and there's no return line, which is now pretty standard in newer models. 

    Michelle Singh sent a comment suggesting that it might be vapor lock if I've been using mogas;  I've been using 100LL avgas for the past 4 days. Michelle, I'll definitely watch your husband's video about this. For anyone reading this who can help me figure out how to reply to blog comments: that would be great!!!

He doesn't have the materials to install a return line and suggested that when I have to climb high, I do step-climbs: climbing 2000', then flying straight and level for ten minutes, then climbing another 2000', then straight and level for another ten minutes. That will give the fuel time to adjust to different temp and pressure, if it IS a fuel vaporization issue. By following highways instead of a direct GPS line, we won't have to fly higher than about 7000' and after we pass Las Cruces, NM we'll be flying much, much lower. 

Blessings on my good friend Jeff Warner, who called this morning and said that if it becomes necessary, he will hitch up his trailer to his truck and come get me. A reassuring Plan B - which I hope never becomes necessary!

Dennis got back from the mine tour and said he enjoyed it. It's late afternoon, and Dennis is taking a nap in the airport office while I'm in Eric's hangar writing this. We will stay in Bisbee for the night and start our flight east in the morning.

Here's a Google Earth view of Bisbee Municipal Airport, and my track for today.