Categories: all aviation Building a Biplane bicycle gadgets misc motorcycle theater
Sat, 23 Jun 2007
I feel like my "maybe, could be" plans about building a plane are starting to firm up. To recap:
Mid-July last year, I had a sudden and powerful yen to build an airplane. I talked myself out of it as being too expensive (which it is) and horrible for the environment (which it is). Then, in June this year, I came back to the idea, and it started to sound good again. It's still expensive, but has always been manageable. It's still bad for the environment, but I'm kind of looking at it as using my "gas ration" that I'm not using any more (the last time I bought gas was... weeks ago, maybe?). Between living in Fremont (ie, 5 minutes' walk from work), and being able to bike damn near anywhere I need to (including Boeing Field and the top of Queen Anne hill -- I'm almost invincible!), I'm not feeling so bad about the whole fossil fuels equation any more.
Anyway, so now, I'm starting to develop a coherent plan. The most appealing choice of plane so far is the Ragwing Special II:
This is a plane which is only available as plans (which I previously considered extra-crazy, but have come around on), and the plans are $100. That means it costs me $100 to dip a toe in the water and see what I think. First thing I can build is a rib, which is a built-up structure about 3 feet long and shaped like a geometrical fish. I'll eventually have to build ~40 of them, so building one gives me a taste of what I'm in for without spending more than a few bucks in wood and a couple hours of time.
The plane that eventually springs forth, fully formed from the aether (ahem), flies at around 90-100 mph cruise, and will use around 3.5-4 gallons per hour. That's over 25 mpg in reasonble circumstances. I'll be doing better than the majority of cars.
It'll have two seats, and the weight capacity to carry a moderately heavy passenger, particularly if we make it a short flight with minimal fuel (to keep weight down). That gives me a chance to fly my dad around, which is one of my definite goals, even if I only ever do it once or twice.
The current engine of choice is called a Jabiru 2200, and is an 85 HP four-cylinder, designed specifically for airplane use. It's spendy, but over the likely 2-4 year timespan of building, I can probably find one used for a lot less than the new price. I read somewhere that the recommended maximum weight for the engine is 180 lbs, so that knocks out most of my other choices, such as the Rotec R-2800 radial, or a Continental C-90/O-200. Besides, if I keep the engine light, then I have that much more weight capacity available for passengers.
I know I'm going to want at least a basic electrical system (I could in theory build a plane with no electrical system at all, and hand-prop the engine -- it's lighter, but I'd rather not). I'll want electric-start on the motor, as well as lights so I can fly at night, and enough equipment to fly over Seattle (a transponder and a radio).
I've had some interesting thoughts about lights using some of the new super-bright LEDs they're putting in flashlights. I figure that using 6 of them together is enough for a landing light, and they can also be used for position lights on the wingtips and tail. A major advantage of LEDs is they use much less power, so the wires don't have to be as fat -- and that means less weight (see where I'm going with all this?). Also, the less equipment I have to run, the smaller the battery can be, etc. etc. Light weight is key.
A worry I'd had on this project was pondering spending $8-20 a foot (not board-foot either!) for aircraft-certified spruce. That is, until I found out that the local lumber yards carry spruce, and for about 1/8-1/15 the cost. I can self-certify the wood according to the same spec and methods the Army and Navy used in WWII (when a lot of wood went into a lot of airplanes), and come out spending much less money. I even have clever plans for how to test ultimate strength on the wood I choose, so I know how it compares to the wood with the official seal on it. That combined with information on wood equivalencies make me pretty confident I can do this without breaking the bank.
In fact, the only big tool I "need" which I don't already have is a table saw (or radial-arm saw, I'm not sure which is a better choice yet). There are also about a million clamps and doubtless a small truckload of other things I'm not thinking about, but none of it feels overwhelming or scary.
After all that, the one thing I haven't decided yet? Whether I'm actually going to do it. It sounds grand, but I haven't come solidly to the conclusion that it's a project I should undertake. That one will come with time. Check back in a year or two, and the answer should be clear.
Posted at 23:33 permanent link category: /aviation
Categories: all aviation Building a Biplane bicycle gadgets misc motorcycle theater