Airframe and Powerplant

Shaking Things Up

May 1, 2003

A Superior new engine!

In just a few months the FAA is expected to do something it hasn't done for 46 years — it will issue a type certificate for a new light-aircraft aircooled reciprocating engine. When Superior Air Parts (SAP) receives that approval, Textron Lycoming and Teledyne Continental Motors (TCM) will have to contend with a third light-airplane engine manufacturer.

Textron Lycoming and TCM may not yet be shaking in their boots because of the arrival of the SAP four-cylinder 180-horsepower SP-360 engine, but a few prophets say that Superior's entry into the light-airplane engine market can be likened to a pre-earthquake tremor in the long-established bedrock of the light-airplane engine marketplace.

A few may argue with the first new-engine statement by pointing out that 81-hp Rotax engines were type-certificated in 1994 for installation in the Diamond DA20-A1 aircraft. The relatively short 1,200-hour time-between-overhauls (TBO) interval and the dearth of experienced Rotax mechanics helped Diamond decide to select the more robust (not to mention more traditional) 125-hp FADEC (full authority digital engine control) fuel-injected Continental IO-240 engine for its DA20-C1 airplanes. The Rotax was also the original engine of choice in the Liberty XL-2 before it too was replaced by the bigger IO-240.

Superior dates to the 1960s

Superior Air Parts carved its initial}niche in the light-aircraft engine industry by obtaining FAA parts manufacturing approval (PMA) for what are referred to as piece parts — parts such as valves, ring sets, gears, bearing sets, piston pins, and pistons that could be legally substituted for manufacturer's parts in Lycoming and Continental engine models — as far back as 1967. As its inventory grew, the PMAed parts list expanded and many builders offered owners a choice of parts during engine-rebuild preplanning. In addition, commercial operators often opted for Superior piece parts. The PMAed parts were always less expensive, typically 15 to 30 percent less expensive, than the manufacturer's parts.

In 1992 SAP offered a PMAed cylinder for the Continental O-200 series of airplanes. In 1994 SAP's Millennium line of cylinders hit the market. In a move that reflects the push toward the stated goal of "fulfilling a new owner's expectations for a new engine," SAP improved its cylinders by introducing the Millennium Generation II cylinders in June 2002. And by the end of 2003 it will have certified an engine. Superior's on a roll, but this upswing is very recent since the previous owners attempted to redefine the company in the late 1990s — with disastrous results.

The piece-parts business provided owners and engine rebuilders with an option when buying engine parts. The Superior PMAed alternative also kept prices down by virtue of that most American of business practices — competition. In addition to its PMAed parts inventory, the company was open to other profit avenues. In the 1980s, Superior opened parts distribution warehouses at various aviation centers throughout the country. When I was living in Alaska, I called the Superior distribution center in Anchorage then I needed a ring set for one cylinder of a Lycoming O-235 C1 engine that powered my Piper PA-12. Superior parts were approved and legal to install with no further FAA approval, and the SAP parts cost less than the Lycoming replacement parts.

The slowdown in the sales of new general aviation airplanes in the 1980s affected Superior in two ways. Because of the huge drop-off in new-engine sales, the big two — TCM and Textron Lycoming — entered the engine-rebuilding arena. As they grabbed an increasing share of the rebuild business, Superior's business slowed.

The management at Superior began to look for other profit avenues, and decided to build piece parts for turbine engines. The idea looked good under the pencil for two reasons — the profit margin for one PMAed turbine wheel was much larger than it was for a bushel basket of reciprocating engine parts, and the piston-engine market was shrinking. Bigger profit potential brought tougher competition. During the veer toward the turbine market, Superior's core business — piece parts for reciprocating engines — was allowed to languish.

In 1997 Superior went bankrupt. R.S.T. and W., a venture capital firm, was an unsecured SAP investor prior to the bankruptcy. Realizing Superior's potential, it quickly proposed a bankruptcy solution to the court and obtained the company. Bernie Coleman, who was SAP's vice president of sales and marketing prior to the bankruptcy, was asked to take over as president. It's evident that Coleman had a plan when he agreed to take over at SAP.

The all-new SP-360

The SP-360 engine, and the XP-360 — which Superior has sold to users in the noncertificated market for more than a year — looks a lot like a copy of the highly regarded Lycoming 360-series engine. The Lycoming four cylinder is renowned for its durability, and the Superior engine should be every bit as durable. Since the application for a completely new airplane engine type certificate gave Superior the freedom to create a clean-sheet design, it wove in a number of selling points.

SAP designed the engine case halves for good oil flow — the pressure oil distribution galleys at the outlet of the pump were split (instead of running down one side, crossing at the front of the engine, and running back on the opposite side) so that the left path of oil flow is dedicated to feeding the hydraulic lifters, and the right half supplies oil to the camshaft and main bearings. Superior believes that this feature eliminates oil pressure fluctuations and lessens oil temperature variations within the engine. Superior's director of product development, Keith Blockus, says that Superior's split oil distribution system reduces the possibility of case fretting (where the two case halves move and rub against each other) since there are smaller temperature variations between the case halves. Oil squirt nozzle bosses are machined in each new case. This permits the installation of nozzles to squirt pressure oil at each piston. The continuous oil bath absorbs heat and lowers the temperature of the pistons and cylinder walls. The oil system also routes pressure oil to the thrust face of the crankshaft, thus reducing the possibility of crankcase wear.

The initial FAA approval will cover four 180-hp engines — the parallel valve carbureted O- and fuel-injected IO-360 engines with fixed-pitch (-A1A2) and constant-speed (-B1A2) applications. Three mount configurations — the #1 dynafocal, the #2 dynafocal, and the conical — further expand the application options. The next stop in the SP-360 engine line is a 200-hp version that will be for sale when angle-valve cylinders and counterweighted crankshafts are approved in the future.

A plenum design incorporated in the oil pan features smooth turns that increase the airflow through the induction system. The result is what Blockus terms "optimized port flows" into each cylinder. "We think the attention to induction system detail will add up to 6 percent more power."

In addition, the camshaft lobes have been tweaked in the overlap timing and rate of valve opening and closing. This results in reduced loads on the camshaft lobes and lifters. In addition to the features already described, the SP-360 also includes crankshafts that are dynamically balanced and forged out of modern vacuum arc remelt (VAR) steel, a strengthened engine case half design, statically balanced pistons and connecting rods, and a set of Millennium standard-cast cylinders.

When Coleman took the helm in 1997, he agreed to manage Superior under three conditions — that the company be sales driven, that he be given free rein to pick his own management team, and that the company concentrate on airplane piston-engine products. The new owners said OK, and Coleman soon set down plans for getting under way.

Coleman hired Tim Archer and made him responsible for sales, marketing, warranty, and product development. Archer was well experienced in piston-engine products, having worked for TCM from 1974 until he left in 1996. When Coleman called, Archer was at Kelley Aerospace. Some people told Archer that SAP was a bad bet. Coleman promised two things — Superior was in the reciprocating engine business to stay, and they'd have fun. That's all it took — Archer's been on board since the beginning of the new SAP.

When I visited Superior last September, Archer had just returned from another trip to Europe. "I was in Europe clearing up the confusion about PMAed parts. That's proved to be profitable for us because we just got a letter from the Germans that approved the installation of PMA parts."

Parts that are approved under an FAA PMA are important to Superior. The first complete PMAed cylinder Superior produced — the O-200 cylinder — was another cog in Superior's strategy.

The first Superior cylinder

In 1977 the FAA issued airworthiness directives (77-13-03 and 78-19-02, both superceded by 96-12-06) requiring O-200 owners to retard the ignition timing from 28 degrees before top dead center(BTDC) to 24 degrees BTDC to prevent cylinder cracking. Resetting the timing slowed cylinder cracking because, with all other factors being equal, retarding the timing reduces the cylinder peak internal pressures. But there was a cost, because retarding the timing reduced the engine power output of the O-200 — an engine that did not have a lot of power to begin with.

In 1992 SAP introduced its first complete cylinder assembly — a PMAed O-200 cylinder that the FAA accepted as strong enough to allow owners who installed the SAP cylinder to reset their ignition timing to the original 28 degrees. As Blockus said, "The PMA process is the American way — it allows competition in the market." Competition has always been part of the Superior strategy, but any MBA will tell you that while competition is good, exclusivity is even better.

Thielert and Superior

There's a lot of interest in compression-ignition (diesel) engines for airplanes. The diesel option promises increased TBO, lower gallon-per-hour fuel consumption, more readily available fuel, and compliance with environmental regulations. Although as many as five companies (see " Future Flight: Horsepower of a Different Color," August 2000 Pilot) were at one stage or another of diesel engine development in late 2000, only two — the SMA six-cylinder 230-hp SR305 and the German four-cylinder 135-hp Thielert Aircraft Engine called the Centurion 1.7 — have progressed to powering flying airplanes (see " Diesel Dawn," November 2001 Pilot). The SMA SR305 engine received an FAA type certificate in July 2002. STCs are being developed for installations, and airframe manufacturers Cirrus Design and Maule Aircraft have ordered engines.

The Centurion 1.7 engine is a four-cylinder, liquid-cooled FADEC turbo diesel ( In spite of a horsepower rating that sounds anemic, the thrust levels generated are nearer that of a 180-hp engine. On December 9, 2002, two Centurion 1.7 engines powered the new Diamond Aircraft ( DA42 TwinStar in its maiden flight. Superior Air Parts has secured the exclusive worldwide (except Europe) rights to this nifty new engine. According to reports, Superior has plans to offer the Centurion 1.7 with the engine control unit (ECU), a 12- or 24-volt alternator, and the propeller reduction gearbox for under $20,000. This engine is currently being flown (in Europe) in Piper Cherokee and Cessna Skyhawk models, with FAA approval for STC-approved installations pending. Obtaining the exclusive rights to a New Age diesel engine, and developing and introducing a new type-certificated general aviation engine, shows that Superior is not resting on its laurels.

What's next

Both Superior and Thielert are in the process of developing new engines designed to compete in the 300-hp marketplace.

The Superior strategy is to obtain PMAs for the parts on a part-by-part basis — thus expanding its core piece-parts business — and then apply for type and production certificates for each new engine. The production certificate is an important part of the puzzle. The reason? Superior has never before been in the engine-building business.

Readers may remember the Superior Air Parts Millennium IO-550 engine that was installed in the 2001 sweepstakes Bonanza (see " Bonanza Sweepstakes: Firewall Forward to the Future," April 2001 Pilot). Wasn't that a new engine? The short answer is no. Superior's preowned Millennium engines all feature new Superior PMAed parts, and a matched set of new Millennium cylinders, and are built in accordance with the highest standards by a hand-picked collection of high-quality engine rebuilders, but the engines are not built at the Superior facility. But that's about to change.

The new facility

On January 10, 2003, Superior kicked off the new year by announcing that it had signed a long-term lease for a new building that will house its state-of-the-art engine production facility.

The production facility will be adjacent to the corporate headquarters, which is just north of the Dallas-Fort Worth airport. Why has Superior decided to change its tried-and-true formula to take on the rigors of engine production?

Because engine production is part of Superior's — and Coleman's — goal of being "the company to go to for power for general aviation."

"The Millennium engine concept was just a steppingstone in the New Age manufacturing techniques we can bring to general aviation engines," says Coleman. The Millennium engine program will continue to be a part of Superior's business, but it's just one part of Coleman's plan to expand Superior's footprint in the GA engine business. Coleman's first five-year plan brought improved (Millennium II) and new cylinders (ask SAP about its investment cast heads), extended parts and labor warranties, the Millennium engine line that forged cooperation between a manufacturer and field shops to produce high-quality standardized engines, and a completely new GA engine. Next will be a 200-hp 360 and a 300-hp engine. Let's hope Coleman has another five-year plan that will provide as many innovations for the GA engine market as the last one did.

E-mail the author at [email protected].