I'm on a business trip to Chicago. I had an interesting experience on the way up.
I got up really early and grabbed a motor pool car. Early enough that I was playing the radio for something to drive to. The radio was the usual modern type with "seek" buttons, meaning that the radio will select channels in that direction until it finds one that's reasonably strong and stops there. That way you don't have to be fooling with it trying to find stations while you drive.
Well, this particular radio seems to be way too sensitive in selecting stations. It stops on about every other frequency slot, and so I ended up hearing weak stations, or stations overlapping. It was very annoying.
At some point I realized that a completely manual tuner would have worked much better in that particular instance; like the sort that were in car radios even 20 years ago. My revelation was that I was so used to tuning radios the electronic way, that my initial reaction wasn't to wish for an older style radio, but to be cross about the over-sensitivity of that one.
It's amazing how much better one feels after 10 hours of sleep. Off to shower, then to work.
I was visiting with one of my loyal fans this evening, and we were discussing the differences between two-stroke and four-stroke engines. I really didn't (and don't) have a fast explanation as to why they're different.
So I did some googling to find a web page with an explanation of the differences. I found a couple that were adiquate, but not very illustrative. Then I ran across keveney.com. Mr. Keveney has a site that has wonderful animations of different types of engines. I like the site even more because the html is simple and the animations are animated gif files, not flash or some other dumb thing. Here is their illustrations of a two-stroke engine and a four-stroke engine.
The explanation at the bottom of the two-stroke page mentions that they are have more power per weight of engine then four-stroke engines, but they pollute more. Another difference between the two is that in the four-stroke engine, the fuel-air and combustion all takes place at the top part of the piston. The bottom of the piston (where the crankshaft lives) has lots of oil in it, so it can be very effectively lubricated. The bottom of the piston in a two-stroke engine also is used to push the fuel and air around, so there's no dedicated oil bath. You have to mix oil with the gas so that the crankshaft gets some lubrication. This arrangement means that two-stroke engines wear much faster than four-stroke, and must be overhauled much more often.
It was also pointed out to me this evening that comments are set to only be registered users. I hadn't realized that meant that people had to register with blogger and have a blog to comment, which wasn't at all my intention. So comments are opened up now. I've heard of popular blogs being spammed in their comments; I guess I'll cross that bridge when I come to it.
Have a good weekend...
So what's this thing about building airplanes that I've mentioned?
Short version: It is legal for a someone to build a airplane for the purposes of their own education, and to legally fly that airplane in the US (and many other countries too, check your local listings for showtimes and channels). The aircraft has an airworthiness certificate as an "Experimental: Amateur Built" aircraft. This is as opposed to an manufactured airplane, say, a Cessna 172, which is a "certificated" airplane, in perhaps the "normal" category.
So--you can build your own airplane. That's nice, but it leaves the rest of us who aren't aeronautical engineers and powerplant mechanics out of it. Well, the spirit of capitalism shines again, and so there are lots of companies out there that will sell you a complete set of plans to build and airplane. Some companies go farther than this and sell a kit, where some of the pieces are pre-fabricated, leaving some of the work for you. Basically, the way the tradeoff works is the more money you spend, the faster you can put the airplane together.
Once the airplane is built, then you can maintain it, which makes the cost of ownership per year less. Of course, you're paying for the kit or materials up front, rather than with a loan, unless you can find financing for buying the kit itself. And you have the satisfaction of flying something that you built with your own hands.
So...for a couple of years, I've been kicking around the idea of building an airplane. I think it would be great fun, and it would be neat to have something to fly that wouldn't cost an arm and a leg for maintainence. For quite a while, I've been interested in the Dragonfly, a composite tandem-wing aircraft. It's fast, light, and runs on an auto engine; either a VolksWagen or a Corvair. (Composite construction was made popular by the designs of Burt Rutan.)
However, I've realized that something that has an advertised build time of 1500 hours is very likely not a good first project airplane. There are an awful lot of kit airplanes that get purchased and then get sold, partially completed. I really don't want to be part of that statistic. So a few weeks ago, I went through a publication of the EAA that catalogs airplane kits and planes, and lists their performance specs so that you can compare them easily. I looked for designs that were less than $10,000 and less than 500 hours to build.
That came down to about 30 designs, which given the many hundreds in the catalog is pretty slim. I decided that for a small, simple airplane for me to build and then just sort of fly around the local area in, there's no reason to have two seats. I'll mostly be flying by myself, and on the occasions that I'd want to take somebody for a ride, I'll just rent something.
Some of those designs were pretty nifty, including a guy in Missouri that sells kits for WW 1 fighter replicas, including a red Fokker triplane made famous by the Red Baron.
However, I quickly discovered that the vast majority of the airplanes in my narrow constraints are powered by two stroke engines. Two stroke engines must be overhauled much more often, and are just not lubricated as well as their four-stroke bretheren. The reason that they're used in small, light aircraft is that their power to weight ratios are significantly higher. However, I really don't think I want to have to deal with one.
Ok, so back to the catalog, an look for cheap airplanes that are fast to build and that run on four stroke engines. This cuts the options down to about half a dozen. I'm currently look at the Hummel Bird, a very small single seat, metal airplane powered by a 1/2 VW (that's a Volkswagen engine with only two cylinders). Sitting here, right now, a Hummel Bird with full fuel and me in it would be about 3 pounds over gross weight. That's the bad news. The good news is that it's very cheap to build, and builds fairly fast. There's a fly-in in northwestern Ohio on Hummel machines and 1/2 VW engines, and so I'm going to try to attend that; to see how tight of a fit it is to sit in one, if nothing else.
More about building airplanes later...
I have a few new pictures of the cats up, for those interested in those sorts of things. Particuarly a couple of photos of Jasper and Pangur meeting a hermit crab.
I'm in Colorado Springs at the moment, home of the United States Air Force Academy and Pikes Peak, on a business trip. I was on the aisle seat, so I didn't have much of a view out of the window, but I got some good looks at Colorado from the air as we were maneuvering to land. It took me a while to realize what I was seeing--the crops were formed in very distinct circles. I finally realized that I was seeing the patterns of the irrigations systems; out here being pretty dry, at least some things only grow where they can be irrigated. It was a little bit like seeing an optical illusion, except that my visual perception didn't change, but the logsticical interpretation.
We had a long layover in Chicago, and I got to sit at the departure gate and listen to the air traffic conrol frequencies for over an hour. Air traffic at all large airports is controlled by people talking to each other of radios. The language that controllers and pilots use is extremely fast and difficult to understand at first. My very first ride in a private airplane was with my uncle when I was 7 or 8; I remember thinking that he was completely incomprehensible when he talked on the radio. As a private pilot, I don't expect I'll be spending a lot of time flying in or out of really big airports like O'Hare, but when I fly to towered airports, I want to be able to hold up my end. I want to be as professional as possible.
While I can't practice talking on the radio, I have taken up listening to airport radio traffic when the chance presents itself. If I'm working on something low-key at work, I'll occasionally listen to webcasts of tower traffic. But when I'm near enough to an airport, I'll take an airband radio along. When I was in Eagan, Minnesota earlier this spring, the hotel we were staying in was in the approach area for the Minneapolis/St. Paul airport. For three evenings, I got to sit and listen to traffic flying in and out of that airport on the radio. (I also realized that the radio I had wasn't very good, prompting me to get a much nicer one:
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Learning to listen to that sometimes extremely fast and infomation dense speech has been interesting for me, both in learning how to understand it from a practical level, but also the learning process itself. I took a little German in high school, and a little Japanese in college, but I've never really learned another language such that it really stuck. I've heard the phrase "the language instinct" but I'd never really thought about it. I've been able to make great strides in being able to extract useful information from radio transmissions just because I'm now somewhat used to listening to them. Occasionally, I miss words, but for the most part I can follow what's going on, and understand what the instructions mean.
By the way, traffic on this blog has gotten high enough that there's a bump in traffic when I create a new post. Looking at the usage reports, I would guess that there are 30-40 readers. Hello out there! I'd be particularly interested in finding out how people found this blog; please leave a comment or drop me a line over e-mail and let me know how in the world you found it; I don't think it's advertised anywhere.
Craig sleepy; must get shut-eye. G'night.
I took a trip to Wisconsin this last weekend to move my sister from River Falls to here in town. I am happy to say that Ryder is still the extremely high class outfit that I remembered it to be. The 10-foot cargo van that I drove up and back was brand new; I doubled the milage on it during the trip. This one actually had built-in blind-spot mirrors:
You can see front of the red car out the window and in the lower mirror; there's effectively no blind spot. (Yes, I was looking at the road when I took it. I just took the camera and held it up and took a blind photo; this one happened to get just want I wanted.)
My car audio playing system at work:
Yes, the truck had two power jacks, and I was using both of them.
This is thanks to:
My travel electronics kit. Yes, when I go on trips, I take separate piece of luggage with me to hold all the electronics. It's rechargable batteries, and chargers, and a long ethernet cable, and other stuff. I decided last year that it was dumb to hunt down all the chargers and adapters and things that we only use when we're away, and it would make much more sense to just store them in a bag and then take that bag with us.