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Thread: Cobalt Aircraft
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Old 26th Jul 2010, 12:14
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Genghis the Engineer
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Join Date: Feb 2000
Location: UK
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Very pretty, but....

- Looking at it in side view, it looks likely to be directionally neutral to unstable

- Reducing the cruise performance to CAS, I get about 195kn at 75% power, which sounds in the right order.

- Whilst I can see the point of double fins to enhance directional stability, I can't really see the point of a V-tail with a canard, there should be no need for separate pitch control to the canard, and all it's going to do is introduce unwanted pitch/yaw coupling.

- Nice to see a 4/5-seater being designed with a sensible payload.

- It may have a good short take-off distance (although I reckon that's 1300ft roll, not distance they're quoting), but with 65kn stall and a canard, it'll eat runway on landing.

- The tiny canard should minimise the known canard gust aggrevation factor, but also will give almost certainly very poor pitch stability and I'd anticipate problems with the longitudinal pitch damping.

- Very interesting, and I'd seriously consider the job of running the flight test programme if anybody wanted to ask for me!

G
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