Sunday, September 16, 2012

Tribulations

I had another occurrence of a Harbor Freight tool causing me some problems, but we'll get to that later. There are times when The Freight can be pretty irritating - just last week I dropped in to buy a handful of trifling stuff, only to find that (yet again!!) their POS (point-of-sale, but the other meaning too) system was locked up. Twelve Angry Men is more than just a Henry Fonda movie, if the visages of the impatient customers were any indication. I turned around and left.





Continuing on my stumbling path down the final stretch, I started out by changing a fuse. Bill H. had left me a note alerting me to the fact that the 2 amp fuse that I had put in the 'START' slot of my fuse panel might be insufficient and that a discussion with Van's had won him dispensation to replace it with a 3 amp fuse. While the plan page (for which there is no newer revision than what I have) stubbornly holds to the lesser of the two....


... the spare fuse block has seen the light.


I started out easy (or so I thought) with a couple of small-box installations. First was the Emergency Locator Transmitter (ELT) pilot-controlled ARM-ON switch. The primary means of turning on the ELT is to fly into something solid, but there are cases, such as surviving an off-airport landing way out in the boonies, where the pilot may need to manually turn on the device. The switch is normally set to the 'ARM' position.

The switch is held in place with irritatingly small nuts.


I'm not sure there is a small enough wrench or socket available for these nuts, but even if there is, I don't have one. I resorted to vise grips.


The ELT switch comes with labels and such that would show the correct positioning of the switch, but Van's tells us not to use them; they will be sending their own version eventually. The intercom gets installed under the ELT switch, but the ELT switch is small enough behind the panel for that to not be as big a hassle as it could have been.



The ELT itself rides back in the baggage area. It uses an internal antenna mounted to a little slab of aluminum. The plans show the ELT antenna mount being screwed into three open holes in the structural cross bar.


Imagine my surprise when I found those ostensibly open holes to not be open!


I went back and found the page where the rivets were originally put in - I was correct in putting them in. There may be a revision page out by now that has current/future builders leave those holes open. I kind of doubt it, though.

The holes will need nutplates behind them. A screw gets run through a nutplate backwards so the 'ears' of the nutplate can be used as a drilling template.


Getting those nutplates up into the cross bar was an exercise in finger dexterity, and served to remind me that I hate exercise of any variety!


The plans then call for the mounting of the ELT mount to the side of the plane. Perusing the contents of the big box that the ELT came in left me wondering "What mount??"


Oh, there it is! Already mounted to the ELT.


Cleco it in place - nothing to it!


Find these oddly shaped rivets. They're hidden in one of the brown paper bags.


I've never had an ELT that had a warning buzzer, but it's a pretty good idea. If you accidentally set off the ELT and don't know it, you'll be on the hook for a $175 replacement battery if you let it run for more than an hour. That, and you'll have the FAA and possibly the Coast Guard breathing furiously down your neck.

The buzzer needs a second ground wire and a pair of splices crimped onto it.


And here it is, neatly installed.


As I plugged in the little connector in the front of it, though, I nearly jumped out of my skin when the buzzer immediately started emitting a very loud and very strident series of beeps. The ELT was on!! How could that have happened? I turned it off just as quickly as I could (once they're on, they assume that you want them to stay on) find the sheet of "accidental activation" instructions included with the unit. That got it turned off, but did not answer the question of why it turned on in the first place. And the bulk of the instructions provided with the ELT were on CD-ROMs, which are utterly useless to me in the hangar.

I decided to shift gears until such time as I could go home and read them. It is only permissible to activate an ELT for testing purposes at the top of the hour (and even then, you only get a five minute window and the activation must be brief) so testing the problem would take awhile. When I got home, I scanned through the docs looking for a trouble shooting guide. One thing I noticed was that the drawings of the remote switch varied in which switch position was 'ON' and which was 'ARM', with 'ARM' being the position I wanted. And there I was, with no labels installed to help me tell the difference. Fortunately, I had pictures of someone else's panel that I could refer to. Sure enough, I had the switch set in the 'ON' position.

Duh.

But that all came later. I decided to finish the installation of the ADAHRS box, which is the box that does all of the air data calculations for the Skyview. As I was looking at the plans, I noticed that Van's doesn't like the DB-9 clam-style backshell for this particular connection, so I had to use an alternative style.


This style is slightly more complicated to put together the first, second, and third time you try one.




With that done, I went ahead and installed the ADAHRS box to the two supports provided (having been warned by Kyle, Work Avoidance Technician for The Jackson Two) before riveting them onto the airplane, and I am glad I did! It would have been a nightmare otherwise. By the time I riveted those brackets in, the ADAHRS had its pitot and static lines connected, and the DB-9 and the OAT plugs installed. The wiring back there will still need to be straightened out, but I was getting cramps from all of the contortions required when scrunching around in the baggage area.

I was just about done for the day, but I decided I'd install the GPS antenna. It looked easy enough.


It wasn't. I couldn't get it to align with the provided screw holes because the wire bundle was being obstructed by the hole in the mounting panel.


I filed a notch in the mount and was then able to screw the antenna to the mount, but when I went to install the mount onto the shelf on the firewall, I had the same problem.


I filed another slot, this time into the shelf. Unfortunately, I may have gone a little too Shogun when filing the edges to smooth them out. The Harbor Freight file broke.


There then ensued a prolonged search for the lost piece of file. The search, to date, has been futile and will have to continue before I can move on. Here's a lesson, though: when using Harbor Freight files, think 'Geisha', not 'Shogun'.

At least I was done enough to get the antenna mounted.



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