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Copied from AvWeb this morning:
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LANCAIR WINS FINAL TYPE APPROVAL FOR COLUMBIA 300
The bubbly was flowing last week at Lancair's Bend, Oreg. facility after
the FAA signed off on the final Type Certificate for the company's first
production airplane, the Columbia 300. Said Lancair founder, president
and designer Lance Neibauer, "Now we're ready to build some airplanes,
and I can't tell you how good it feels to say that." Lancair expects to
deliver the first Columbia 300's to buyers by the end of the year.
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More power to the whole gang!!
In reference to the "how does the air get out" question, it's one of the greatest Lancair mysteries that has yet to be solved! I have two of the rinky-dink adjustable NACA scoops installed (sorry about that, too because after a some time in use, they never close nice and flush, like they did when new), one on each side, that I never got around to ducting to anything (Hey! Don said keep it LIGHT - and before he grew the mustache, he was really intimidating!). They blow a fair breeze at cruise when fully open and therein lies the mystery. I didn't like all those openings in the back of the airplane, giving critters (and the elements) access to the nooks 'n crannies in and around the tail things. So I closed as much of it out as possible, including the cut-out in the rudder and the rudder cable funnels. (On the older models, those were open to the tail cone and looked like small reverse scoops - I think they've been eliminated from later models). So I have nearly all those exit areas closed off, have a nice seal around the canopy and still get plenty of air flow thru the scoops. Go figure! Seriously, you can close all the things I did and as the scoops put a little positive pressure in the wheel house, it'll merely exit thru the aileron pass-thru's in the inboard rib. So, unless you've built the first pressurized 320/360, don't sweat it.
Concerning the nose gear door problem, nobody's come up with a good explanation as to what's causing it (around here, anyway) but it seems to have been fixed (on two 235's I know of) by merely carefully bleeding the hydro line up to the fitting on the door cylinder. Mine hissed and spit quite a bit of air and fluid mist when I cracked the AN fitting and tapped the sequence valve with the gear switch "up", following which, the "problem" went away (do this with the nose gear and door cylinders disconnected so you don't get caught by the gear and door swinging into place, and have a helper available to turn the Master switch "off" once pure hydro fluid starts coming out of the cracked fitting). I doubt that the main gear doors are candidates for this problem as they are pumped down as well as up and the fluid in the back side of the piston has to be pushed out against a significant amount of pressure, while what would be the "down" connection to the nose door cylinder is open to the air (no back pressure other than the spring). Again, this is no answer to the question about the cause, but at least the bleeding has seemed to stop it. I guess you could plumb a line to the down side of the cylinder, like the mains and it would probably work - but, since mine seems to be OK now, I'll leave it as is.
The folks at Radio Systems Technology (RST), the kit avionics outfit, used to publish a neat little booklet on how to make the copper foil antennas, including how to determine the required length, orientation, etc. They also had the materials available (copper foil strip and appropriate ferrite toroidal "donuts" to use with RG58 coax.). I don't know if they still have these things available but it is definitely worth checking out. They also had (have?) a kit for a transponder antenna that can be mounted internally and is one hot antenna! I've never been "lost in space" by ATC and I know they can "see" me in places where I've been invisible in a rental 182! I used RST's foil and ferrite materials kit in conjunction with the booklet to design and build my VOR, MB and GS antennas, and also installed their Xponder spike inside a wing tip. The VOR antenna is built into the horizontal stab and has an enormous range, the MB is length-wise in the fuselage bottom (and works like a charm - misc. control cables and push-rods notwithstanding - I get a clear tone and light even at 2500 - 3000 ft above a marker beacon ground antenna - which might even be too good!) and the GS is in the wing-tip opposite the Xponder spike. The calculations are simple and the antennas work as good, and in many cases, better than commercial antennas. If you are building a mostly carbon airplane, you can probably disregard all of the above.
From the ads section of the EAA magazine: RST Engineering, 916-272-2203. Don't know if they still have the booklet and parts available (they should, in my opinion) but it's worth a call.
Charlie Kohler's story about how useful his L-IV is almost convincing me that I need one after I retire - big, case cracking Conti and all.
To Bill Gradwohl, I looked long and hard at the implications of using Hexfets to control the various bits and pieces and decided that simple was better. I used the automotive 70 amp relays (some here have touted the Bosch units while I used Potter & Brumfield, though there are many sources, even including RS) where a Hexfet might have been used, for the following basic reasons: 1. Simpler electrically - even with the relatively simple drive requirements of the big FET, it still has a few more parts than a switch, relay and diode. 2. Simpler mechanically - the relay requires NO heat sink which, depending on the load current, the Hexfet might. Which means, also, that if you need active cooling you'll need a fan since ram-cooling air isn't available until you're moving, and the Hexfet will need cooling as soon as it's "on". That is, unless you want to carry around a massive hunk of aluminum heat sink heavy enough to meet any contingency (like No.10 for take off with ambient temperature pushing 90 - happens around here enough to be considered). These DC rated automotive style relays have a very good failure rate with the main life limiting consideration being related to number of operations - which in our service is low. 3. Cost is close to a push, depending on where you get your parts (either kind).
To Jim Solensky, you have the interesting one, Jim! Every other episode of the hydro-pack running-on in little bursts as you described - including mine - was on retraction immediately after the pump initially stops running with the gear in the wells, doors closed. I've had it happen and I know a friend's 230/320 here at Torrance,CA has too. It only happens once in a while, doesn't seem to follow any pattern and I don't know why it stops. It most often gives 3 - 5 little "blips" of the pump then all is normal, I might see it once in 2 - 3 months, or on 3 subsequent flights - then not again for months. Hardest thing to fix, random glitches, ain't this fun?
On the fuel system debate. If you've got a couple hundred trouble-free hours on your airplane's fuel system, in the hot as well as in the cold (more importantly, hot), at various altitudes, no matter what your system looks like, it's a great one by definition, and we could all learn something good from it - and appreciate your fortitude at being a test pilot. Engineering loves and demands rigor, but it doesn't ignore success. Engineering also does not ignore failure - you "engineer" something into your fuel system that doesn't work, e.g., something breaks or you suffer a vapor lock or whatever, and we'll all learn something from this too - with the main difference being that in the second case, it might not matter all that much to you. On the way down, you may be for a relatively short time, the proud owner of some totally unique and totally useless information. The message being, if there's a system configuration in use that works, particularly in critical areas like fuel, use it. Remember, as long as your engine ain't broken, and you insure a proper supply of fuel, air and spark, it has to run.
Cheers,
Dan Schaefer
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