New-Generation Trainer

The company created the C1 in 1998 as an improved version of the DA20 Katana. The newer C1 Eclipse was powered by a 125 hp Continental IO-240. The little Continental brought fuel injection to the low-horsepower regime and helped make the airplane more acceptable to the crucial American market. Fuel injection improves fuel distribution between cylinders and helps reduce total fuel burn by allowing leaner cruise power settings.

By the end of 2005, Diamond had sold almost 350 of the Continental-powered DA20-C1s. At an average price of $130,000, that represents nearly $46 million. In today's market, that's a financial hit by anyone's standards.

Such success wouldn't have been possible without a significant improvement in the number of student starts, and Diamond hopes to capitalize on the upswing in interest with its own flight training centers. According to Jeff Owens, vice president of Diamond Aircraft, the company is poised to launch a chain of Diamond Flight Centers sometime in early 2007. "We have one facility in place now, the Diamond Brilliance Flight Center in Naples, Florida, but that's strictly a test bed intended to help us examine the flight training market," says Owens. "We hope to open the first actual DFC by the first quarter of 2007."

A number of flight schools have already recognized the value of the C1 and have purchased the type to feed the recent resurgence of interest in primary flight training. Ben Walton, president of Summit Aviation at Gallatin Field Airport in Bozeman, Mont., owns and operates a trio of Diamond C1s for flight instruction. He feels that the airplanes are nearly ideal for his applications.

Summit Aviation is the contract flight school for Montana State University's recently initiated flight-training program. "Until two years ago, MSU had no aviation program," explains Walton. "I started teaching a groundschool class at the college back in 2000, but the state didn't offer a degree in aviation. In the short span of four semesters, enrollment in the groundschool class jumped from 25 to 50 students, and it was obvious there was plenty of interest in a baccalaureate aviation degree. I made a presentation to the state, and after considering it for a year or two, they finally launched the training syllabus in 2005."

When Walton was given the go-ahead on Montana State's aviation program, he initially considered the new-generation Cessna Skyhawk for his primary trainer. "That was the conventional choice," Walton comments, "and we already had a post-1997 Skyhawk on the line that was fairly popular. Someone suggested that I check out the Diamonds, so I flew over to Seattle to look at one. I was very impressed. The C1 is a good-looking airplane, it's very comfortable inside and it uses a conventional center stick rather than a side stick or a yoke. Diamond has also designed the airplane with a nonsteerable nosewheel. This allows for excellent maneuverability on the ground. It can reverse direction in practically its own wingspan, and I knew that would be popular with students.

"The airplane's climb and cruise performance were actually better than the Skyhawk's, and the economics made a lot more sense," says Walton. "The four-place Skyhawk was about $50,000 more costly than the Diamond, and the C1 was much less expensive to operate. For pure flight training, there was just no need to haul around an extra 700 pounds and two additional seats. On top of that, reduced instructional power settings can lower fuel burn to 4 gph, and with today's escalating avgas prices, that's an important advantage."

Though MSU's aviation program has only been in place for three semesters, it's already attracted 30 full-time students, some of whom fly as often as five times a day. To feed such demand, Summit currently operates three Diamond C1s, a pair of Diamond Stars and a Piper Seminole for commercial and multi-engine training. Collectively, those three models can take a student all the way to commercial, multi and instrument ratings. The Summit staff includes nine full-time instructors to handle both the college students and private flight-training candidates.

Walton feels the Bozeman area is almost ideal for flight training. "While we are surrounded by mountains, the Bozeman area is in the wide Gallatin Valley, a beautiful part of southwest Montana with a great climate and four ski resorts nearby. Bozeman Airport is a large, tower-equipped field, and we're scheduled to get radar service in March. It's a true winter playground and a great place to fly all year round."

That's the good news. The not-so-good news is that Bozeman resides at an elevation of almost 4,500 feet, not necessarily the best environment for low-powered flight trainers. "Our lone Cessna 150 is a little weak in the summer, as performance isn't exactly stellar in high-density altitudes," Walton explains. "On a hot summer day, we may see only about 300 fpm in the 150. Even a modest summer temperature of 80 degree F generates a density altitude of 7,000 feet.

"The Diamond C1 has no problem with the altitude," Walton continues. "Normal climb out of Bozeman on a standard day is still 700 fpm, and even when it's warm, the C1s usually score 500 to 600 fpm going uphill. On top of that, the students love the C1. It's obviously a 21st-century airplane in contrast to the older Pipers and Cessnas on the field."

There's little question that the C1's swept, modern design wins friends among aspiring pilots and old pros alike. In keeping with Diamond's sailplane tradition, the Eclipse offers uncommon glide and efficiency. The airfoil is a European Wortmann FX-63 section, a combination of short chord and long span that results in an aspect ratio of 10.2. In contrast, a Bonanza's aspect ratio scores only 6.2, and a Warrior's registers 7.2. (Aspect ratio is the proportion of chord to span; all other things being equal---which they almost never are---the higher the aspect ratio, the more efficient the wing. High-performance sailplanes make excellent use of the high-aspect-ratio wing.)

The C1's cockpit is housed beneath an overhead hatch that folds up and backward for entrance to both seats. Accommodations are uncommonly roomy, wider than just about any other two-seat trainer. Aft of the front office, the waspish empennage translates to a graceful T-tail, mounted up out of the propwash to minimize pitch excursions during power changes.

Despite what may appear a delicate structure, the composite C1 is actually stronger than its counterparts. Diamond's airplane is certified in the utility class (capable of withstanding 4.4 positive G's) and is certified for spins, a valuable but uncommon talent among trainers.

One interesting aspect of the C1: it isn't certified for IFR. Yes, you can equip the airplane with full IFR instrumentation and avionics. You can even train for the instrument rating under the hood in the airplane operating in VFR weather, but you can't fly in actual IFR conditions. Diamond hasn't yet obtained lightning-strike certification from the FAA, so the airplane is limited to VFR operation.

In keeping with its intended role as a primary trainer, the C1 flies very much like a Grumman American Trainer with a stick rather than a yoke. The Diamond trainer manifests similar control characteristics---granted push-pull tubes for roll. No one will mistake a C1 for an aerobatic airplane, but the Diamond's quick handling and enthusiastic throttle response makes it a fun machine to fly.

Cruise performance and cabin comfort are good enough that Diamond sells many of its C1s to individual owners rather than flight schools. At 135 knots max cruise with 24 gallons in the tanks, the airplane can range out 410 nm in three hours with a reasonable reserve. Private owners love the airplane's spacious interior and excellent performance.

Perhaps best of all, however, stall characteristics are about as benign as you could hope for. Instructors know there's a direct correlation between stall speed and good landings, and the C1's full dirty stall speed is a slow 45 knots. That means a student can make approaches as slow as 60 knots if necessary. Nothing happens too fast, and the airplane flies so slowly, it's fairly easy to finesse the Diamond trainer onto the runway.

At this writing, there are only two other dedicated trainers being produced, the recent Liberty XL2 and the American Champion Aurora. The XL2 is a purpose-built aviation teaching machine in a similar configuration with the same engine, and it offers performance similar to that of the Diamond C1. The contrast between the C1 and the Aurora couldn't be more pronounced, however. The tandem Aurora is a fabric-covered taildragger loosely derived from the old Champ, whereas the C1 is its own airplane, as modern as tomorrow. The C1 and XL2 have most of the aces in performance, whereas the Aurora wins the short-/soft-field competition.

It's old versus new, and good arguments can be made for both types. If you prefer the classic handling of a tailwheel, the Aurora may be your bird, but if you'd rather benefit from 21st-century design and performance, the Diamond C1 Eclipse or Liberty XL2 may be the better bet.

SPECS: 2006 Diamond DA20-C1 Eclipse