A Sign of the Zodiac (Part 5)

The devil really is in the details.


A Sign of the Zodiac (Part 5)

The devil really is in the details

by Rick Lindstrom.

I’ll admit that I’m an optimist (most of the time, anyway). I’ve found that maintaining a generally positive outlook makes it much easier to get out of bed each day, as opposed to giving in to that rare cloud of angst that sometimes appears just as the first cup of coffee finishes working its daily motivational magic. And, as my Corvair-powered Zodiac 601 XL kit neared completion in the fall of 2006, I’ll admit to occasional fits of giddiness and even mild euphoria. For it is an amazing thing to see a fully functioning airplane appear, firsthand, where there was only a pile of parts a short time earlier. Best of all, the first flight was close at hand, and I’ll (somewhat sheepishly) admit that I actually fantasized during weak moments that it would be absolute perfection in every regard. It didn’t take long for aviation reality to set me straight. If there ever was a first flight of a homebuilt where every item and system worked perfectly as advertised, I’d like to hear about it. Because my own experience, and that of the other homebuilders I know, was far from spot-on ideal—in spite of having freshly issued FAA paperwork that loosely promised that this airplane should work well enough to accumulate 40 hours in a 50-mile radius from Massey Skypark in Edgewater, Florida, before being turned loose on the rest of the world. Ultimately, the bugs were vanquished and the hours were fl own off in time for the Zodiac’s public debut at Sun ’n Fun 2007, but it didn’t come easily. I did learn the true meaning of the word “Experimental” along the way.

I’d much prefer to report that everything went like clockwork without a single hitch. But that’s not how it actually happened. Instead, there were multiple failures, some electrical and some human. So if you’ve been reading this series expecting nothing but glowing prose about the wonders of building this project, you’ll most likely be disappointed by this reality-based installment. I’d suggest turning from these pages to the Robrucha cartoons instead so as not to spoil the mood.

Still reading? Good. Especially if you’re tired of the Pollyanna-ish hype that infects this industry every now and then. You know what I mean, the occasional “too good to be true” promises from vendors and suppliers that tend to rear their ugly heads during the peak of convention season. I suppose it’s human nature to want to believe it all just when we need to be at our skeptical best, for it takes no small measure of discipline to really research all the claims and make solid purchase decisions in the heat of building. I plead guilty to performing less than due diligence when selecting the ideal complement of avionics and instrumentation for my project. Rest assured, I later paid in full for my lack of attention to unpleasant details.

The Tyranny of Deadlines

I suppose the major difference between a good decision and a bad one is that the good variety never sneaks up behind you and bites you. One of the worst things we did in the early stages of the project was to shoot off our mouths and promise everyone who would listen that we would absolutely without question have this airplane at AirVenture 2006. Worse still, people actually believed us, and we did a lot of verbal backpedaling during the convention when asked, “Hey! Where’s your Zodiac parked?” The usual reply: “Uh, Florida?”

There were several valid reasons that the airplane was still in the hangar in Edgewater, but we could’ve saved a lot of explaining and some amount of our personal reputations by not imposing this particular deadline on our ourselves. Nothing angers those sinister gremlins that bedevil homebuilt projects more than confidently challenging them with the careless comment that you will actually be flying at a certain place at a certain time. If I ever undertake another airplane project, I will only say that the airplane will appear somewhere when it’s sufficiently debugged, flight-tested, and the hours have been flown off . That way, everyone involved (including the builder), can avoid making the situation worse by adding the stress of inflexible deadlines. Having a completion goal to shoot for is one thing, but firmly committing to a specific date is quite another, and the added pressure only sets the stage for the builder to be less than diligent in crucial aspects of the project.

The Allure of Leading Edge

Because various avionics technologies may be evaluated in the Zodiac, I needed to have the permanent equipment mounted in as small an area of panel space as possible, while still retaining good legibility in flight. Th e particular requirements of the Corvair automotive conversion made the selection of engine instrumentation even more interesting, and not being constrained by FAA requirements as they apply to certified aircraft, the choices for engine monitors were many. I-K Technologies had just introduced a capable engine monitor that could display most everything I wanted to monitor with both LED graph segments and a precise digital display, and all in a 4×4-inch square package. Perfect! The only hitch was, it hadn’t yet been installed with a similar Corvair engine. At the time, I didn’t worry much about this.

No one can seem to resist an EFIS (electronic flight instrument system), and so I took signed on for the Blue Mountain G4 Lite, a compact system featuring a virtual Horizontal Situation Indicator and a color GPS moving map that also displays potential terrain conflicts. Because it mounts in a standard 3.125-inch instrument hole and the front bezel also takes up roughly a 4inch square of panel space, it would be the ideal complement when mounted next-door to the I-K engine monitor. The only problem was that Blue Mountain wasn’t shipping just yet, but I was told it would be just a matter of a week or two. I happily wrote the check, again ordering something that had yet to fly in a similar airplane. For some naïve reason, I didn’t much worry about this either. (Do you sense a pattern developing?)

The Allure of False Economy

There’s no such thing as used “latest and greatest” instrumentation or avionics, so I thought I might save a buck or two and find a used transponder and communications radio. My local avionics shop had a tested King KT76A transponder available, and a quick eBay search netted an allegedly fully tested King KY197A flip-flop radio that wasn’t much to look at, but should work well enough. After a lackluster bidding skirmish in the final minutes of the auction, it was mine. That alone should’ve told me something.

It took longer than it should have for the KY197A to arrive, and when it did, it was a mess. It looked just as bad as it did in the auction photo, and worse still, the display was a scrambled mess of random segments when powered up. I did two things at this point: I filed a complaint with eBay and gave the battered radio to the avionics shop to see if it could be salvaged. After some educated poking and prodding, the shop pronounced that the radio could be repaired for roughly what I paid for it. Distasteful as it was, I said, “Go ahead.”

Getting the seller of the King radio to respond to my complaint was not fruitful, and I ultimately gave up trying to get a refund, partial or otherwise. So I ended up buying a decidedly ugly but functioning radio for twice what it should’ve cost—and for more than what a brand new ICOM IC-A200 would’ve run. Such a deal, eh?

Analog Dialogue

Something in my gut actually won the decision to install traditional round “steam gauges” for some of the functions, and I selected several 1-inch miniature gauges for left and right fuel levels, voltmeter and ammeter. The UMA fuel gauges would replace the much larger VDO gauges that come with the kit, and the small size of the UMA units would allow them to be placed very near the beautiful Andair fuel selector. The fuel senders that come with the Zodiac have their design roots in the old VW Bug, and aren’t much used anywhere else. With such a bone simple fuel indicator system, complete with tried and true round dials, what could possibly go wrong?

I clearly recall the flurry of phone calls to different vendors during this period of time, ordering up all of the smaller but vital parts needed to be installed and flown well before AirVenture 2006 rolled around. Relying on my hazy former bug-owner memory instead of double-checking the resistance range of the senders, I ordered what I thought were the compatible fuel gauges. Once again, taking a few minutes to ensure the compatibility of a critical instrumentation component could’ve saved hours of troubleshooting later when time really became a critical factor. Funny thing: I actually thought I was being efficient while getting these items quickly ordered and on their way to Florida.

Nothing Flies without Paperwork

Sometimes you do everything right, and still things go off track. I had reserved the N number 42 Kilo Papa with the FAA, and also ordered the nifty Amateur-Built registration packet from the EAA, which contains everything the builder needs to stay on the good and legal side of the feds when hatching a new airplane. For around $20, the packet contains a step-by-step guide to registering and getting initial airworthiness certification for your U.S.-built project, including needed panel placards, data plate, and a big “EXPERIMENTAL” decal to adorn the cockpit entrance.

The EAA strongly suggests allowing at least 90 days to submit the paperwork to the FAA for approval and turnaround before initial flight-testing begins. With just under three months to go, I sent the forms off to the feds in Oklahoma City, and waited for their response. And waited. And waited. By the time I got through on the phone to the FAA Registry Branch to follow up on my paperwork, time was short and it looked like making the Oshkosh flight might actually be in jeopardy. Worse, the FAA confirmed that they had no record of receiving my paperwork, and I’d have to do it all again. I think the guys in the hangar in Edgewater could hear my screams from my office in California.

Why the number 42KP you ask? The KP is shorthand for KITPLANES®, and Douglas Adams fans will recognize the number 42 as being the answer to life, the universe and everything.

Won’t Fly Without Instrumentation

I had originally planned my panel to include one of the Dynon systems, but I was also considering the Blue Mountain unit. Because the editor of this magazine had already chosen the new big-screen Dynons for his project, and because it’s worthwhile to sample as many different systems as we can, I went with Blue Mountain. As time grew shorter and shorter, and my bought and paid for unit failed to ship when promised, I really started to wonder if making AirVenture was possible.

Because the Blue Mountain G4 Lite does so much, there was absolutely no way the airplane could fly without it. Repeated calls to company headquarters resulted in no firm delivery dates, only guesses. As the guesses came and went, it became way too late to abandon the Blue Mountain unit for another system and re-engineer the panel. In fairness to Blue Mountain, I fully understand and agree with their reluctance to ship any system that hasn’t been completely wrung out and debugged. However, repeated optimistic promises of unrealistic delivery dates only served to prolong the agony of anticipation when other solutions could’ve been considered in time to meet our looming deadline.

As it turned out, the G4 Lite was finally ready to ship, but not until the day before we were scheduled to fly out on our annual sojourn from the West Coast to Oshkosh. Close, but no cigar.

Tick, Tick, Tick

Without the needed FAA paperwork and a functioning instrument that displayed airspeed, rate of climb, attitude, turn rate, heading and altitude, there was no way we could schedule an inspection and fly off the required hours before taking the Zodiac to the convention, so the mood was indeed glum as we realized 42KP’s big debut would just have to wait for another event.

The annual Zenith Fly-In in Mexico, Missouri, which was a few weeks after the close of the 2006 Oshkosh show, was briefly considered as doable, but it would be tight trying to get everything finished, tested and the hours flown off and still make the event. Cooler heads prevailed, and we decided that November’s Corvair College at the home base in Edgewater would be the new, new place for the first flight to occur.

Finally! Flight!

The 2006 Corvair College was scheduled to start on November 10, and we were shooting to conduct the first flight on the 6th, which also happened to coincide with my 53rd birthday. Again, I had illusions, this time of my best birthday gift being to fly my very own Zodiac 601 XL for the first time. And once again, a variety of system maladies forced us to postpone the actual aviating until early the following morning, just before the Corvair College attendees started drifting in.

During the high-speed taxi tests, the Blue Mountain G4 Lite had a disconcerting tendency to lose the horizon reference during acceleration and deceleration, and the heading indicator had east and west reversed, while north and south matched up to where the airplane was actually pointed.

The I-K unit had its share of questionable readings, contradicting what was seen on the test stand when the engine was first run in for 5 hours. Oil pressure appeared low, oil temperature appeared high, and fuel pressure was about half of what should be expected. There was no tachometer indication at all.

The engine and the airframe felt solid and strong, but the brakes howled and shuddered tremendously whenever applied. There didn’t seem to be enough elevator effectiveness to hold the nosewheel just off the pavement as the airplane approached flying speed.

With these new factors in the mix, the first and only flight on November 10 consisted of project lead Gus Warren making a single circuit, verifying that the airplane indeed was capable of controlled flight, and ending by taxiing in and shutting down. My first flight in my own airplane would have to wait until January of the following year, due to a conflict of personal schedules and the approaching holiday season. Nuts.


Once again, in all fairness to the manufacturers, a number of the instrumentation maladies that we initially encountered could be traced to installation errors, most likely sneaking in during our quest to meet some self-imposed deadlines. But the good news is that I learned a tremendous amount, both about building a light aircraft and more importantly, about myself. Because the whole homebuilt movement is centered on education, this project was actually paying off in spades. And each aircraft system shortcoming or challenge presented was ultimately identified and overcome, which is the subject of our next, and final, installment of this series.  

Previous articleAugust 2007
Next articleSeptember 2007
Rick Lindstrom
Rick Lindstrom has been fascinated with motorized devices since the disassembly of his mom’s Kirby vacuum when he was 3, predictably followed by record player motors and lawnmower engines. After he learned to fly, it was only natural that he gravitated to the world of alternative aircraft engines. He currently pilots a Corvair-powered Zenith and is undecided about what will power his GlaStar.


Please enter your comment!
Please enter your name here

This site uses Akismet to reduce spam. Learn how your comment data is processed.