Monday, September 1, 2008
Epic LT: King Kong Turboprop
Rick Schrameck’s single-engine turboprop has incredible power, performance and payload—and it’s a homebuilt
|Nearly 30 years ago, I spent several days at Nellis Air Force Base in Nevada, participating in a Red Flag exercise and flying the amazing F-15 Eagle with Lieutenant Colonel Timothy O’Keefe, veteran fighter pilot and then-commander of the 433rd Fighter Weapons Squadron. For a general aviation pilot, the F-15 experience was an eye-opener into the world of the ultimate fighter, an exercise in maximum speed and seemingly limitless power.|
You’ll also lose virtually all forward visibility in the climb. As with most high-speed aircraft, the better compromise is a quicker forward speed in exchange for a lower deck angle. That’s a trick piston pilots have been using for years to keep engines cool, obviously not a concern on a turboprop.
I flew the LT on three occasions in conjunction with this article, and in one departure out of Santa Monica, Calif., ATC granted an uninterrupted climb from near sea level to 18,000 feet. I used 200 knots in the climb, and the result was a consistent 2,000 to 2,500 fpm, relatively unaffected by increasing altitude.
With such upward mobility on tap, the Epic LT’s maximum altitude of FL280 comes up in 12 to 15 minutes. Such abbreviated climb makes it reasonable to file for FL270 or FL280 on practically every flight. Flying high makes turbines more efficient, and that can be the case even when the winds aren’t in your favor. The trade of fuel for speed is simply more efficient in the upper flight levels.
|A bright, comfy place to fly, the LT’s cockpit features a glass-panel Chelton system and a two-piece windshield that provides unusually good visibility.|
With 1,200 hp on tap and the largest propeller produced by Hartzell out front—a 108-inch diameter, four-blade—to translate horsepower to thrust, the LT might be a logical candidate for flight at RVSM altitudes (above FL290). Considering that the homebuilt kit costs $1.525 million and RVSM certification can add an easy $70,000 to the price, it’s unlikely anyone would choose that option. When the certified Epic Dynasty comes to market (at about $2.5 million), plans are to certify the airplane for FL310 or higher, so RVSM will be an option.
If you’re looking for max speed, you’ll want to stop the climb at about 22,000 feet. At that height, the LT can deliver cruise speeds more reminiscent of a VLJ than a single-engine turboprop. The book suggests 340 knots under optimum conditions at the proper altitude, but in the real world, 330 knots might be more realistic. That’s a respectable number considering that neither of the two newest, certified light jets on the market do much more than 350 knots on a good day.
Where the LT will leave the jets behind is in range. With long-range tanks and economy power settings, the aircraft can reach out and touch a destination more than 1,500 nm distant. Economy cruise settings consume about 53 gph, and with the large, optional 350-gallon tanks topped (on the production version), you can plan on 5.5 hours plus reserve at about 280 knots.
Because beta or reverse thrust provides propjets with dramatic stopping power, turboprops typically have an automatic advantage over jets in landing mode. In the Epic LT’s case, landing over a 50-foot obstacle requires less than 1,900 feet. That’s at least 1,000 feet less than any of the jets and equal to or better than the other leading turboprops.
As mentioned above, Epic is currently working on certifying a production version of the LT, known as the Dynasty, with Transport Canada. At this writing, the only Epic available is one you’ll have to build yourself or, at least, with the company’s help. On the surface, that might seem a significant disincentive to the kind of pilot who can afford the LT. There have been at least 35 of those aviators who have stepped up to the plate; another 40 are waiting to start their LT, having stepped up to the plate and put both their money and time on the line. If Epic can do that well with a homebuilt turboprop, imagine what the company might do with a fully certified airplane. SPECS: 2008 Epic LT
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