With Wings As Eagles: Tech/Computer/Electronics Entries

New Pretty Gauges

2014 April 24 21:55

I was planning on blogging every day in April. Ha. I got busy and went to the MAPA convention and got delayed (again) until I could fly the plane back and I've just been busy. I should stop promising to do that.

Anyway, the airplane is physically flyable, annualed (so it's legal to fly) and back home. Yay! Here are a few photos of the gauges while flying back the last leg from Bowling Green.

Here's the stock 6-pack engine cluster.

The upper right gauge, the old ammeter, has been replaced by a new digital one (see next photo) and so it's marked INOPerative. The important thing here is the bottom three gauges are all firmly in the green (actually, the cylinder head temp, the lower right one, is basically below; this plane cools superbly well at cruise).

And here's upper-right side of the instrument panel:

In the lower left is the stock manifold pressure gauge and fuel pressure gauge. In the upper left is the new Horizon Tachometer. I really like how it looks and how it works. The area in the center was a blank panel up to this winter's annual. The orange engine meter (bar graph thing in the center) was all the way over on the right where the blank round panel now is. I moved it closer so it's easy for the pilot to see it and get at the switches. The third meter, the one with the single switch right below it, is my new volmeter/ammeter. I got it because the stock ammeter just didn't read very well.

The area in the center that's shinier black is a panel that I fabricated. The engine monitor is an older electronics piece, so it's fairly long and kind of heavy. THe extra screws that you see in the panel are attaching reinforcing rails to the back of the panel. Two of the breakers are for the new instruments. The third is for the engine monitor; it had been protected with an in-line fuse from the avioincs panel, but I wanted it on all the time, so I instead put a breaker and now it's powered from the main bus. And in the upper right is the control/sense plane for the new ELT (emergency locator transmitter).

Box-shaped Beacon

2014 April 05 09:46

Since we decided to have the engine overhauled for our airplane after the prop strike, and the airplane was going to be up for annual anyway, I figured that was a good time to take care of all the stuff that needed to be worked on and that would take calendar time, since the time was incurred anyway.

One of the things I knew was up was the ELT batteries. Every civil airplane in the US (with certain limited exceptions) is required to have an "Emergency Locator Transmitter" (ELT) on board. This activates if there's a sudden shock (because of a crash) and transmits a signal so that search/rescuers can locate the plane by radio signal. The ELT is internally-powered by batteries. Modern ELTs are supposed to have a panel in view of the pilot that allows the pilot to turn it on or off, and indicates whether its transmitting. In any case, I knew that the batteries in the ELT were due for replacing this annual anyway.

My plane didn't have an ELT panel, so I'd been thinking about that. So when I was at Oshkosh last year, I bought a used ELT (very cheap) with a new install kit. First, I thought that it would be interesting to look inside and see how they worked. Second, I though perhaps that the install kit would allow me to put a panel in properly.

So, first step was to look at the old ELT and replace the batteries. It turns out that there were problems with the old one; it had broken mounting. Its batteries were also the style that had to be replaced by a specialized battery pack, not with off-the-shelf batteries.

So I asked my mechanic if we could just use the used one that I'd bought, which, as it turns out, can be batteried with Duracell D-cell batteries. He said it was fine to do that, as long as it tests out correctly. The one thing I needed to do was to clean off the battery terminals. At some point someone had left batteries in it too long, and the terminals were a little green.

So here are the battery terminals, nice and cleaned up and shiny:

Here's the ELT sitting on the desk, batteries in and tested. The cord is plugged back into the ELT itself to act as an emergency carry strap. Patches the airport cat looks on.

Here's Patches inspecting the left wing navigation light.

One thing I had to do was run the control cable from the back of the airplane where the ELT sits to the control panel, which I installed in the front instrument panel. Here's the left side of the body, with the interior mostly out, with the cable (which is really a phone wall cable) installed and indicated with red arrows.

And here's a close-up of the center section:

And finally, the ELT installed and ready to go, with the cable plugged in and the unit tested.