Been away from the shop a bit. Christmas with the family, shopping, work etc. There are important things in life besides airplanes I suppose :) That doesn't stop me from doing reasearch. Okay, you can call it browsing if you like. I wanted to share a website I found called experimentalavionics.com One of the biggest decisions to be made with my build is what avionics I want in my panel. This of course is guided by the three points of mission, cost and simplicity in that order, although they aren't mutually exclusive either. Simplicity generally leads to lower cost. Mission needs vs wants can also directly influence cost up or down. With a bit of work, the following items can be built very inexpensively, with off the shelf parts and instructions found online. My aircraft mission is simple enough. I don't need to go fast or high (the Zenair 750 isn't pressurized nor is it a speed demon) and I won't be flying IFR (instrument flight rules). I do want good communications (it's actually what I do for a living!) and the ability to navigate outside the normal ATC coverage areas to some of those good fishing/camping spots. I'm using a converted Corvair automobile engine. Instrumentation for this is simple too. The idea of building my own EMS (Engine Monitoring System) from open source electronics/software fits both my budget and interests in learning. I have learned enough electronics skills over the years to build it (thanks to Mom and Dad for starting my learning in basic electronics by buying me this when I was a kid). Whether this becomes my primary engine instrumentation or a back up to the traditional analog engine guages will be decided later after I do some more research. It might look something like this: A nice, easy to read display suitable for the 6 cylinder Corvair engine. The bonus is how much panel space I'd save and the ability to datalog the information for testing mods or diagnosing trends. Alarm annunciators (flashing warning lights or audio) can easily be added for any parameter that goes out of range. Cool! The other panel items such as primary flight instruments (altimeter, VSI, etc) require more thought. I like traditional instruments for their familiar simplicity. For the same reasons as the EMS, a EFIS (Electronic Flight Information System) has an intriguing draw, but I'll likely have something like this as my backup instruments: Again, easy to read, simple and space saving. 6 instruments and a clock all in one place. A couple of cons that I'll need to consider are temperature operating range and failure modes. It gets real cold where I'll be keeping the plane when it's built (unless I win the lottery, then it's heated floor hanger all the way!) As for failure modes, how comfortable am I putting all indicators in one place, where a single failure may result in losing everything at once. The website that I linked above also includes preliminary discussions on intercoms for pilot/passenger communication and a WiFi based AHRS (Attitude Heading Reference System) that could link wirelessly to a tablet for navigation. Perhaps someone will adapt the AHRS to be an inexpensive ADS-B out module! Lots to think about... Happy New Year everyone :)
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I've shared my overall plans with many people over the past couple of months. It never hurts to put word out you are looking for something. Sometimes it pays off, sometimes it doesn't, but either way everyone ends up learning more or less as you go. Got a call from a buddy who came across what he thought might be an airplane throttle assembly: Turns out it is a throttle assembly, but for marine applications. I'm thinking it's for a very large twin engine boat with adjustable pitch props. Close, but not what I need. Next, I got a call from another buddy at work who tells me he has a bunch of "on the way to the trash bin" stuff he thought I might be interested in. I grabbed a box of stuff from him that appears to have some sort of bench testing equipment for strobe light assemblies. Among the junk were two strobe power supplies.... ....and five of these strobe heads: Our employer doesn't use this older technology any more (everything now is advanced LEDs), but this could work very well for me and my build. I wired up one of the power supplies and connected 2 of the strobe heads. In my shop they are almost blindingly bright and work in quad-flash pattern, very cool and would be excellent on the wing tips (the video doesn't really capture the brightness well): My only concern is the amount of power that these older types of strobes draw and how much they weigh compared to self contained LEDs, but when something is scrounged for free, it's hard to turn down. If I decide to switch to LED lights during the build, I can always donate (pay it forward) to my Volunteer Fire Department (I do their emergency light installs anyway).
Onto the shelf they'll go for now until I'm ready. On another "scrounging" note, Dad's got his contacts in the old car world on the prowl for a Corvair motor. Yes, scrounging is worth it and all part of learning :) In order for this project to come together, I'm planning on building in sections in order to keep things economical. Overall I'll be spending a fair amount of money, but by doing things in stages, it will keep me from being overloaded by debt.
I figure if I'm going to build and learn as I go, might as well spread the dollars over time as well. To that end, I've broken the project into several "sections" and within those there will inevitably be sub-sections. Airframe I've decided on the type of airframe I want (high wing, side by side). It will most likely be buying something that is a complete fuselage, tail section and wings. Whether that will be fabric or metal or fiberglass or a combination of 2 or 3 is yet to be determined. Tail dragger (conventional) or tricycle gear is also a consideration. Interior This will be largely dependent on the airframe, however the key here will be lightweight materials with a eye towards function and comfort. Avionics The key here will be simplicity. For the type of flying I plan on doing, I really don't need much more than what is required for basic visual flight rules. Now, I'm the first to admit that I am a gadget geek, easily distracted by the latest and greatest electronic systems and gizmos. Unfortunately, there is a big correlation between fancy and expensive. Surely some electronics add to simplicity and by combining several items into one do-all display there might be some money savings, but I'm not sure putting all my money into a single system makes sense. If that single system fails, it will be costly to repair or replace, where an individual component is easier to diagnose and replace where necessary without upsetting the entire apple cart. Perhaps once I'm up flying I can take a look at upgrades, but for now I'll stick with tried and true simple analogue stuff. (Unless I get a deal I can't refuse!) In my next post, I'll talk about engines, a really big topic. |
Time until takeoffAuthorHusband, father and 911 dispatcher. Long time pilot with a licence that burns a hole in my pocket where my student loan money used to be. First time aircraft builder. Looking to fly my own airplane. Categories
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