Looking Forward and Back at Continental


It's been 100 years since Continental built its first engine, and Continentals have powered dozens of milestone airplanes, but its storied history is as much a rap against the company as it is an undeniable measure of success. Most pilots incorrectly believe that Continental is building the same engines the same way it has for decades. But nothing could be further from the truth. Though Continental continues to build and support engines that were first introduced 50 or more years ago, almost nothing about the way the engines are manufactured and the materials used are the same as they were even five years ago. Today's Continental is a modern engineering and manufacturing operation that would surprise any pilot who believes the company is doing nothing more than the same old thing.

The reason pilots believe there is nothing new at Continental is that the direct drive, horizontally opposed, air cooled piston engine remains the most efficient, reliable and economical powerplant for light airplanes. Continental was the first to recognize the superiority of the horizontally opposed engine while others concentrated on radial, inline or V-configured cylinders. The advantages of the horizontal arrangement are so overwhelming that when Honda collaborated with Continental to create a clean sheet aircraft piston-engine design a few years ago, even Honda-widely celebrated for engine innovation-selected the direct drive horizontal design. It is because Continental's engines look basically the same as they did years ago that pilots refuse to believe great progress has been made.

The flashy changes at Continental surround fadec, the computerized system that controls and optimizes all aspects of engine operation. Fadec is important and will simplify flying by automating mixture control, but changes at Continental that are all but invisible to the airplane owner are really as fundamentally important as fadec.

What's been happening at Continental over the past several years is what manufacturing types call process control improvement. Process control is everything it takes to transform metal ore from the earth into a complete engine. The "control" part is creating a system that performs every step exactly the same. The real definition of manufacturing quality is to reduce tolerances at every step so that all parts and procedures are alike. Only through control of the process can each engine be expected to perform the same.

An important part of process control is to automate crucial steps in production, and Continental has invested many millions to do just that. Its actual manufacturing floor space is now a tiny fraction of what it was a few years ago because multi-step procedures-such as milling and finishing a connecting rod-are now all accomplished by a single machine. The same is true for making crankshafts, crankcases and cylinders. In the past each time a human placed the part on a different machine to perform another step in the process, an error could creep in and accumulate. Automation has reduced those errors. Continental also controls the materials themselves, including 100 percent testing on all new crankshaft forgings. The crankshaft blanks, as they are sometimes called, have a small coupon sticking out that is broken off before the blank is machined into a new crankshaft. That coupon is tested to make sure the metal alloy and the strength and hardness levels all meet the specification. Several years ago some improperly forged crankshaft blanks made it into service when Continental used only routine spot testing. The 100 percent testing will stop that from happening again.

Pilots also believe that the design of key Continental engine parts is frozen, but that's not true. The company constantly tweaks the design of components to address problems in the field. For example, cracks in Continental crankcases were a problem a number of years ago, but design changes have all but eliminated the issue in engines built over the past several years. Design improvements have touched almost every part of the large Continental engines, so even though the new engine delivered today is still called an IO-520, for example, it is not the same IO-520 that went out the door 10, 20 or 30 years ago. The one area of Continental engine production that is still done by hand-just as it is at the largest jet engine makers-is final engine assembly where a build team puts the engine together. But even there in final assembly Continental uses automatic torque wrenches to tighten the bolts exactly to spec on crucial parts such as the connecting rod to the crankshaft.

Continental has also improved performance in its engines with balanced fuel flow injectors from the factory and tight control of cylinder head finishing, so that each cylinder draws in an equal amount of air. Engines are also "balanced" with matched rods and pistons, but that's not much of a big deal anymore because the process controls are good enough that all components match very closely. To me the most impressive performance coming out of Continental is the 550 series engines with the cross flow heads that are used in the Columbia, Cirrus, Mooney and others. These engines are clearly producing more than rated horsepower, are remarkably smooth and are delivering good life.

Many pilots don't know that Continental is also a leader in small turbine engine design and manufacturing. Continental jet engines have powered everything from the Cessna T-37 jet trainer in the Air Force to the latest cruise missile.

Thinking back over Continental's first 100 years it's amazing to note the airplanes its engines powered. There was the Cub in the 1930s, and the Cessna 140s, Champs, T-Crafts and others during the 1940s. We're celebrating the 50th anniversary of the Cessna 172 and 182 this year, and both were powered by Continental initially, and for most of those 50 years. Continentals were on all the Cessna twins I can think of, starting with the 310. And, of course, maybe the most important light airplane of all-the Bonanza-was and remains powered by Continental as it comes up on its 60th birthday next year.

The aircraft piston engine gets little or no respect, pilots all dream of turbine power, but the reality is the fuel efficiency and price gap between pistons and turbines is not closing. Most of us will only be able to afford to fly behind piston power, but the good news is that the piston engine is constantly improving at Continental. Hardware improvements are continuous, and fadec, after a long design and certification struggle, is on the doorstep. I do appreciate Continental's heritage-especially when I push the throttles up in my Baron-but I am looking ahead more than back. The next century of Continentals looks bright.

Personal Jet PartyDiamond knows how to build airplanes, but the company also knows how to party. A bash for hundreds of Diamond owners and prospects at the company's London, Ontario, assembly plant in July publicly unveiled the new D-Jet, a single-engine personal jet. Amazingly athletic girls cavorted on ribbons suspended from the ceiling while the crowd sipped excellent wine from Diamond owner Christian Dries' own winery on Pelee Island in Lake Erie and awaited the unveiling of the D-Jet.

As the music reached a crescendo the curtain around the D-Jet mock-up came down on one side of the room while Christian taxied the proof of concept D-Jet in from the other. The flying version of the D-Jet is exciting to look at, but the mock-up that represents the shape of the conforming airplane is more visually appealing.

I find the D-Jet project to be very interesting and believe it represents the real revolution in personal jets. While the proposed very light jets are actually miniature business jets, the D-Jet is a whole new concept because of its single engine and restricted operating envelope. I expect the D-Jet to launch an entirely new market for single-engine jets, as the introduction of the TBM 700 did for turboprop singles when it appeared in 1991. I think the keys to success for the D-Jet are its single engine, which simplifies transition for less experienced pilots, and its 25,000-foot ceiling. Insurance underwriters will be much more comfortable with owner pilots flying a single at 25,000 feet and below, just as they have been with the single-engine turboprops, and that makes the D-Jet available to more pilots. Also, the single engine minimizes cost of acquisition and operation. But, just as I was pointing out above, the gap between jets and pistons is still wide and Diamond announced a price of $1.398 million for the D-Jet. That's less than the cost of any existing pressurized single-engine turboprop, but is still hundreds of thousands more than the Piper Mirage, the only pressurized piston single.

The flying proof of concept (POC) D-Jet has a noticeably humped up canopy over the pilot seats. The production version will have the same cockpit headroom, but the fuselage is reshaped so that the upper surface flows back smoothly to the vertical fin, thus eliminating the hump. The production version is also wider at the hip and shoulder area, creating more cabin room, but the greatest cabin size is where the primary passenger-the pilot-is seated. Though the POC can't be used to collect certification data, it is providing an early indication that the projected top speed of 300 knots or more is likely. The Williams FJ33 turbofan is performing predictably, and Christian announced that the finished airplane should have a thrust-to-weight ratio of around three pounds of airplane for each pound of thrust. A typical twin-engine business jet has about 2.7 pounds of airplane per pound of thrust at maximum certified takeoff weight, and that's with all engines running, so the D-Jet should be pretty sprightly on takeoff and initial climb.

Diamond also announced that it would offer the whole airplane ballistic parachute as an option on the D-Jet. The chute would not be part of the certification as it is in the Cirrus airplanes, but would provide another option in a forced landing if the engine fails.

What I like best about the D-Jet is that it makes no pretenses. It is a personal airplane promising good speed and range, and I'm sure loads of fun to fly, but with the limitations of operating altitude and tiny risk of power loss that owner pilots accept every day. Diamond has a strong track record of success in meeting the goals of its other airplanes, and I don't see any showstoppers with the D-Jet, but to get it into production by early 2008 is a tall order. The project is off to a great start, and seeing a real flying D-Jet raised the level of excitement of every pilot at the party, including me.7