Rite of passage: my first annual

On July 6, my plane goes into the shop for its annual inspection. Because the annual inspection that was performed last year occurred in June, it's legal to fly it until the end of June this year without another one. Because the shop at Harvey Field is as busy as it is, they couldn't get me in until July 6. This means that, next year, I can fly it without an annual until the end of July. I'd like to work the schedule for the annual inspection around the calendar so that, at some point, it's done in fall or winter, but that would take several years at least and is still subject to their available capacity.

Because this is the last weekend in June, I went flying today. During the flight, my airplane developed another apparent fault. This one appears to be with the intercom, or something related to it. So that's another item to add to the list of things to look at and, hopefully, take care of when it's in the shop.

As I started rolling down the runway, which at Harvey Field is a bit bumpy, I started hearing a loud, static-like sound in my headset. It was a sort of cracking sound, as if something was introducing noise into the system, or something was intermittently shorting out. I actually aborted the takeoff and exited the runway. I went over to the runup area and did another runup. Everything seemed fine. The engine was working fine, the magneto checks were fine, mechanically everything seemed sound. So I went taxied back out to take off.

On the second try, the sound occurred again. Everything related to the engine was working fine so I took off and climbed out. After I took off, the sound abated and went away. I was a bit concerned, but the engine was running strongly, all instruments were working, the radios were all working fine, and the sound had quit, so I continued to climb out and depart. I was paying really close attention to how everything was working, though.

At one point, I went into a relatively steep turn. Suddenly the sound returned. I was wondering if it was related to the squelch on the intercom. I turned the squelch knob but there was no effect. I turned the volume knob, but there was no effect. I turned the intercom off, and the sound stopped. I could still hear the radio just fine, though.

The intercom in my plane is in the system between the audio panel and the headset jacks. It serves two purposes: It allows the occupants of the plane to talk to each other, and it provides side tone when talking. Side tone is where you hear your voice in your headset when you're speaking. My intercom has a feature that, when you turn it off, it effectively removes itself from the circuit, and the pilot's headset is directly connected to the audio panel. If there is someone else in the plane, they can't hear your speak, or vice versa. Also, you won't hear your own voice unless you are transmitting, in which case the side tone is provided by the radio itself.

After some experimentation, I determined that the noise occurred if there was increased g force downward, such as when doing a steep turn or when in bumpy air. I tried plugging my headset into the passenger side jacks but I could still hear the sound so it wasn't specific to the pilot's jacks. I suspect there's a loose wire of some kind, either in the intercom itself, or one of the ones connected to it. It is either intermittently shorting out, or disconnecting. The sound being a sort of popping sound instead of constant I attribute to vibration from the engine.

So, yet another squawk for the annual. All told, here are thing things that are scheduled to be fixed:

• Replace the left half of the stabilator trim tab as the existing one is cracked. This will depend on whether the replacement arrives in time, if it hasn't already. If not, we'll just have to do it later; the plane is still airworthy.
• Replace the landing light. This will also depend on whether the replacement arrives in time, if it hasn't already. It should already be here.
• Re-attach the rubber wing root seal on the underside. I've been keeping an eye on it and it hasn't worsened.
• Push the passenger door hinge pin back up into place. It's about an inch lower than it should be. I've been watching that also, and it hasn't gotten any worse.
• Re-attach the honeycomb-like skin stiffening material on the left side of the rear fuselage.
• Replace the bulb for the red interior night light. Hopefully that's all that needs to be done and there isn't an issue with the wiring or the dimmer knob.
• Lubricate the fuel primer pump.
  
• Check out the issue with the intercom I encountered today.
• Clean a bit of corrosion from a couple of inspection covers and paint them.
• Clean out the rest of the mess from the bird nest.

Of course, there's a decent chance that one or more additional items will be discovered during the inspection. That's to be expected with a 47 year-old airplane. I hope it won't be in the shop too long, though. This is prime flying season, and I don't want to get rusty.

And then there's the cost. Of course, nobody buys an airplane like mine as a financial investment. From a strictly fiscal standpoint, it's rather unwise. The annual inspection is generally the greatest expense each year. And the inspection, plus the additional work listed above, aren't the only things that will be included in the payment I give to Snohomish Flying Service when it's all done. I had a pre-buy inspection performed during which most of the items on that list were found. It's on me, but I haven't paid for it yet. SFS is basically running a tab and I'll pay for everything at once after the annual. I have no idea what it's all going to cost but I'm guessing at least five grand. It might even be closer to ten. Fortunately, I've put funds aside for maintenance so I'll be able to cover it. I just have to make sure I continue to do so throughout the year so I can cover the next annual, and the next, and so on.

If I own the plane long enough, at some point I'm going to have to decide whether I'm going to spend the money to overhaul the engine, or replace it with a new or factory rebuilt unit. And that's when you start talking real money. But that's several years in the future. For now, it's the regular routine maintenance, and unexpected minor fixes that I'll be dealing with. Hopefully nothing major will need to be done before then.