Turboprops have always occupied a unique niche in the world’s corporate aviation market. The type represents a middle ground in both price and performance between piston twins and pure jets, offering 2,000+ fpm climb and 50 to 75 knots’ more cruise speed than pistons, plus six-to-10-seat capability and the talent to fly well above most of the planet’s nastiest weather.
Perhaps the ultimate benefit of turboprops for the business community is the reliability inherent in turbine engines. Even the most reliable piston powerplants rarely boast TBOs above 2,000 hours, but turboprops can easily offer 3,000 hours or more between overhauls, and they demand less service in between.
King Airs have come to be regarded as perhaps the ultimate turboprops. From the “little” C90 to the large, 17-seat 350, King Airs of all descriptions are almost universally revered as the standard by which other turboprops are measured, and sales records reflect that preeminence.
Furthermore, attempt to define the best of the King Airs, and you’ll eventually home in on the T-tailed model 200. This one model is almost universally accepted as the best all-around King Air on the market and one of the world’s best business turboprops, period. Originally blessed with a pair of Pratt & Whitney PT6A-41 turboprops, developing 850 shp per side, the 200 had six pounds of pressurization and the largest, most luxurious cabin in the class.
Updated with new interiors, engines and avionics, the Beech King Air 200 has proven to be essentially ageless, now more than three decades in production. To date, the Wichita company has delivered nearly 2,000 of the luxury turboprops. At an average $2 million to $3 million per airplane, that represents some $6 billion worth of airplanes, and the company continues to build roughly 40 new B200s per year.
Corporate turboprops typically must work hard to justify their existence, and as perhaps the most popular of the business propjets, King Air 200s log an average of 250 to 300 hours per year. That means many of the early 200s have long since reached their 3,000-hour engine TBOs.
Enter Blackhawk Modifications [(254) 755-6711, www.blackhawk.aero] of Waco, Texas. With international offices in Brazil, Germany and Switzerland, Blackhawk is the world’s leading turboprop, aircraft engine upgrade company, concentrating exclusively on applications of the near legendary P&W PT6A turbine engine. The company is already well established as a modifier on the Beech King Air A90, C90, E90 and F90, plus the Cessna Conquest 1 and Piper Cheyenne I, II and IIXL. Since 2000, the company has generated some 120 engine upgrades of all types.
Blackhawk doesn’t actually do any conversions at Waco, but uses its large-volume purchase power to negotiate better prices for new engines in place of overhauled powerplants. Company president Jim Allmon and his engineering staff conceived a mod that would upgrade early King Air 200 P&W PT6A-41 turbines to the later, improved P&W PT6A-42 powerplants (fitted as standard in post-1981 King Air 200s).
The benefits of the upgrade are obvious. Original -41s are rated for 3,000 hours between overhauls, and the later -42s uprate TBO to 3,600 hours, a 20% increase. Also, though both models are rated for the same limiting thrust and shaft horsepower, the -42 maintains thrust to a higher altitude, permitting higher cruise speeds.
“In a sense, we were nearly ideal candidates for the 200XP upgrade,” says Mike Murdock of Dunagan Joint Properties in Huntsville, Ala. Murdock, a retired software executive, and Deason Dunagan, a well-known Alabama plastic surgeon, are partners on a 1979 King Air 200 that was rapidly approaching TBO a few years back.
“Deason and I both had a little history with other airplanes—Cirrus, Skylanes and a Cheyenne II— but our King Air 200 truly was an exceptional airplane,” Murdock explains. “We had enough familiarity with the market to recognize that there was something special about the King Air 200. It offered the classic Beech handling we’d heard so much about, reliable systems, good performance, excellent cabin room and comfort, and of course, the reliability inherent in the P&W PT6A engines. We really enjoyed that airplane and accepted that it was a cut above most comparable turboprops, but we knew we were facing a major financial decision regarding the engines.”
The partners progressively upgraded every other aspect of their King Air as the engines approached TBO. The Dunagan Joint Properties airplane received a new custom interior with improved sound and vibration insulation, new paint and an avionics upgrade to flat-panel displays. At 300 hours short of engine TBO, however, it was decision time on the next major improvement.
“With the old engines in place, we usually opted to cruise in the lower flight levels, generally 19,000 or 20,000 feet,” Murdock admits, “and our max cruise speeds rarely exceeded 260 knots. Above 20,000 feet, thrust and speed fell off rapidly, and we were pretty much tapped out by the time we reached 25,000 feet. If we needed to fly higher for weather or better winds, the airplane wasn’t enthusiastic about the taller altitude.
“We were, of course, well aware of the Blackhawk conversion, and in many respects, it made a lot of sense,” Murdock continues. “Our existing engines were already second run—they’d been overhauled once and were coming up on their second TBO—and that made the Blackhawk mod seem even more logical, as overhauls don’t become cheaper with age. We knew a second overhaul would cost us somewhere between $690,000 and $750,000—there was no way to pin down the exact price until the engines were opened up.”
Partners Murdock and Dunagan also knew that the benefits of the Blackhawk conversion relegated the price difference to insignificance. At $798,000 for the Blackhawk mod, the -42 engines were only about $50,000 more costly than a common second-run overhaul. The new engines represented a known quantity and a return to zero time, a bolt-on mod, with no weight penalty associated with the higher thrust at altitude. In exchange for the slightly higher price, their ’79 King Air would be reinvigorated with new engines, offering more power up high and a 20% longer TBO. The -42 engines basically upgrade a straight King Air 200 to a B200.
In addition to the engine upgrade, the Dunagan airplane features the Raisbeck Epic Performance Package. Raisbeck Engineering of Seattle, Wash., has long been an innovator of King Air mods, and the current EPIC conversion includes optimized four-blade props, a ram air recovery system, and improved leading edges and strakes. Collectively, the changes add as much as nine knots of cruise to some King Airs, reduce operating temperatures and improve high-altitude performance.
“From a financial point of view, the Blackhawk conversion with the Raisbeck EPIC performance package made so much sense,” says Murdock. “When you combine the advantages of the higher speed and taller altitudes, plus the higher TBO and added aircraft value of new versus overhauled engines, the operating efficiencies paid back the additional investment in a very short time.”
The Dunagan partners converted to the Blackhawk XP mod last year, and they’ve had no reason to look back. Since the installation of the -42 engines, the company has operated the airplane about 100 hours in missions all over the United States. The differences in performance and operating economics have proven the wisdom of their investment.
“Our typical mission profile is probably similar to that of other King Air 200 operators,” says Mike Murdock. “We usually confine our trips to 500 to 700 nm, flying throughout the southeastern United States and the Gulf Coast, but we’ve sometimes ranged out as far as Albuquerque or Telluride. Our load is typically a pilot plus three to four passengers. The nice thing about the King Air 200, however, is that we have the flexibility to carry as many as 10 people total if we need to fly a short-range/heavy-payload profile. I have an early delivery position on one of the new Eclipse VLJs, but we have no plans to sell the 200XP. None of the new generation of little jets will ever offer the passenger loads of our quarter-century-old King Air. ”
Dunagan Properties operates its King Air once or twice a week, and now realizes a greater range of operations than before. “With the -42 engines installed, we’ll often file for FL240 or FL250, several levels higher than we could utilize with the -41s,” says Murdock. “We’re burning about 100 gph up there, but we’re also truing about 280 to 285 KTAS at that altitude, 20 knots better than with our old engines.
“If winds are favorable,” Murdock continues, “we’ll sometimes even file for FL280, the highest non-RVSM altitude. That’s an option that realistically wasn’t even available to us before. At that altitude, we’ll lose about 10 knots of cruise, but burn 15 gph less fuel, so the trade is more than worth it. Also, we’re virtually guaranteed to be cruising in smooth air and sunshine on top of the weather.”
Murdock says the partners expense the Dunagan airplane at about $400 per hour dry and roughly another $400 per hour for fuel. “If you’re going to operate an aircraft in this class,” says Murdock, “you may as well do it as economically and efficiently as possible. The Blackhawk conversion allows us to optimize our investment at the same time we utilize the airplane to the max. For our purposes, the Blackhawk mod is simply good business.”