Tuesday, January 5, 2010

The hardest part about building an RV airplane

Learning to rivet properly was hard. Making the canopy for the RV-7A was hard. Coming up with the money to buy tools and kits was hard. But you know what the hardest part of building an RV airplane is? Keeping from looking beyond the next thing you have to do on the plane.

As many of you know, this is year 9 of the great RV project and for years when people would say, "When will you be done?", I'd say, "About $30,000 from right now." Funny stuff, but it buttressed my discipline to not let others pressure me in the build. It will be done when it's done. It will be built right; except, of course, for the parts of the plane I didn't build right.

When you get nearer to the end of the project than the beginning, I've found it's difficult to keep that sensibility.

I made the mistake a month or so ago of doing some calculating . If I can get the panel completed this winter and if I can get some engine work done this spring, I can have first engine-start by fall. If I can start the engine for the first time this fall, I could be flying some time in 2011.

Let's hit the Wayback Machine. It's 2001, and I've just taken delivery of the tail kit. "If I can finish the tail kit this year, I can build the wings next year," I said to myself and, thankfully, nobody else. "If build the wings next year, I can complete the fuselage the year after that. If I complete the fuselage the year after that, I can finish the finishing kit and be flying the year after that."

Sure, it was possible to be flying by 2005; lots of people have built an RV in four years. But that was them and their schedule and resources; not mine.

Fortunately, I altered my thinking early on and went with the "it'll be done when it's done" mantra.

So, about a month ago, when I was talking to someone at work, I speculated that I could be flying in 2011. That was a mistake. Why? Because now it put me on something I've steadfastly refused to be on -- a timetable. And once you're on a timetable, you put pressure on yourself to adhere to it. Again, good for some people; not me. I've got plenty of things in my life that have to be done by a certain date; this project is my therapy, not another thing that has to be done by a certain date.

This week provided two examples. On Sunday, I finished installing the PS Engineering 1000II intercom. It was time to plug it into the Vertical Power VP-50 system. When I checked my load-planning worksheet, however, I realized I'd made a mistake. I attached a power connector, assuming I'd assigned it to a 5 AMP switch on the VP-50 unit. I hadn't. I actually had assigned it to a 2 AMP pin, which is a different connector on the other side of the VP-50 control box, requiring a DSUB pin.

What to do? It didn't make any sense to waste an open 5 AMP pin on a 2 AMP circuit, but the wire was too short to simply cut off the connector and install the correct one, and I didn't want to splice in extra wire. I'd have to take the wire harness for the intercom apart, pull the wire out and replace it.

"Screw that," I said on Sunday.

On Monday, I started on the next part of the panel: installing the transponder (a Garmin GTX 327), so that I can then install the ICOM A210 radio and be done with all the radio work. That's when I made another discovery. I hadn't cut through the subpanel for the transponder unit because it's shorter than the A210 radio. Why would I need to? Because, I learned Monday night, there's no room to attach the wiring harness to the transponder without doing so.

I did cut through the subpanel for the A210, but I placed a piece of angle across the bottom of the cutout, and that now presents a barrier for cutting through the subpanel to make room for the connector for the transponder.

Did I mention it was 4 below at the hangar last night?

See, that's the problem; It's entirely uncomfortable at the hangar; it's far too cold to be working on metal parts with bare hands. And now I've put pressure on myself to get the panel done over the winter, so I can move on to the engine, so I can start it by fall, so I can be flying by next year.

"Screw that," I said to myself after a night of tossing and turning.

The plane will be done when it gets done. The VP-50 needs to be removed, the intercom needs to be removed, and the cutout solution for the subpanel needs to be taken care of. If it's too cold to do it now, I'll just have to do it later. But it has to be done right.

So, sometime this spring, I'll resume work in the hangar, and get the panel done.

But not until I rewire that intercom harness.


  1. Bob, you have a great blog I’ve viewed it over the past few months, very informative. Since you reside in a far colder climate than I do I sympathize with your winter build downtime frustrations. One way to heat your build area is to hang inexpensive tarps or clear plastic around all four corners with another tarp or clear plastic sheet covering the top.
    Drop lights and portable heaters will easily heat this area to comfortable working temperatures in very little time. Also if you can find an older, used refrigerator you can leave your paint and resins inside of it year round minimizing the shuffling of materials from home to hanger. I understand tight budgets all too well; they’ve hindered my progress a lot.

  2. It is a great job by presenting the information for every one of us. This will let every one know about your hard work and your passion.