Tuesday, December 21, 2010

CGS Hawk Arrow

Notes to self:  took at look at a used single seat CGS Hawk Arrow for sale (ad link).  This one is registered as an ELSA (N4209F), powered by a Rotax 503 DCDI 50HP 2 stroke engine with electric start.  The engine was rebuilt in 2004 and has about 50 hours on it.  TBO for this engine is listed at 300 hours or 5 years, which ever comes first.  It is a simple engine and could be rebuilt for parts cost (link) or by a rebuilder for considerably more.  It has pretty complete VFR instruments, with a hand held radio, but no transponder, electric fuel pump in addition to mechanical fuel pump, an anti-collision strobe, full flaps and in flight elevator trim.  The sails are probably towards the end of their useful life, replacement Dacron would be around $2,200 (link), but would probably go one or two more seasons.  This would need to be tested.  The machine has an almost complete set of vortex generators, but is missing a few and would probably need to be replaced or eliminated on sail replacement. The machine appears to be well built, but was involved in a minor mishap (2004), which is well documented.  The current owner was unable to start the motor, probably the result of old pre-mix gas.  Yes, this requires premix (oil/fuel) gas. But there may be other concerns, as the Rotax (and other 2-stroke engines) do want special care and feeding (there are courses). Links to non-ethanol gas stations in NC. 

There are others Hawks for sale, even listed on one site, and there are a number of similar machines available at various prices, such as the Challenger, Rans S-12/S14 series, Quicksilver, Kolb (M3X), Flightstar, and others.  Check out UFlyit for sales and courses.

CGS Hawk Service Bulletins.

Saturday, June 12, 2010

Airplanes in a box

For many years, I have thought about building an airplane. This goes back many years, when my father and I had the notion of building a Volksplane. In fact, I build a 1/4 scale model when I was doing a lot of models (and a bit a glider flying), powered by a SuperTigre (0.35) engine, which were pretty hard to get hold of in rural Quebec. Still have 'em. Since we're moving, I've started looking into these again. And it is amazing to see how the technology has developed, particularly with the appearance of ultra-light aircraft. I'm currently thinking about something from Fisher Flying Products. The Avenger in the ultra-light configuration is particularly interesting for the rank beginner. The 28 hp Hirth F33 (and here) engine -- single cylinder, two stroke, air-cooled -- is amazing since it weighs in a 35 pounds. Good for 1000 hours between overhauls. Amazing. I think I will go with electric start, recalling just how battered my fingers got starting the SuperTigres, which would either backfire or catch, in both instances chopping your digit with a sharp prop blade. But there are many other options out there. Check out the Challenger. The dream machine would be the BD-5. But that is all metal, a pretty serious machine, and there were problems. The current machine is available from BD-Micro, and powered by a 65 hp two cylinder, two stroke Hirth engine. There are turboprop and jet options.

It is amazing to me that you can fly an ultralight without a license. Thankfully, you can get training from the good folks at USUA and USPPA. Probably a good idea. Helmets are required for motorcycles in North Carolina, unlike Illinois, but I wonder if this includes ultralights. Another good idea in any event.

MotoCzysz E1PC

Finally, an electric bike that packs some serious performance. The E1PC produces 100 hp and can top at least 140 mph. Not close to the stock Hayabusa, but still very impressive. True it broke down at the recent Isle of Man TTs, but this may well be a peek at "the motorcycle of the future". Not indications of weight and cost is astronomical at this time. Well, they are using batteries built by the same folks that build 'em for NASA. Check out related article here. My next bike?

Friday, May 21, 2010

More Google Goodies

Russ pointed out two new Google APIs which are of particular interest. The Prediction API "enables access to Google's machine learning algorithms to analyze your historic data and predict likely future outcomes". It will take your labeled data, run supervised learning algorithms, and allow you to predict. I've not looked too hard, but I don't see just which ML algorithms they are offering (Naive Bayes, SVM, KNN, etc). But how cool is this? Well, pretty cool. But, Russ also points out BigQuery by Google: "a web service that enables you to do interactive analysis of massively large datasets. Scalable and easy to use, BigQuery lets developers and businesses tap into powerful data analytics on demand". Terrabytes, billions of rows per seconds. Wow.

Also check out Lessons learned developing a practical large scale machine learning system. And the first lesson? "Keep it simple (even at the expense of a little accuracy)".

Now these, all by themselves, are a really good reason to learn Python. :-)