Cirrus versus Diamond

In a warts-and-all flyoff between the SR20 and DA40 Star, Cirrus wins on capability but the Diamond flies better.

At the moment, general aviations distant horizon is not, shall we say, emblazoned with bright promise. Aircraft sales are down, owners are flying fewer hours, flight schools are dropping like flies and the feds grow ever more onerous. Yet even in this bleak landscape, flowers bloom and two of them are named Cirrus and Diamond.

Both companies have enjoyed-and continue to enjoy-remarkable if modest success in selling four-place composite aircraft that fly in the face of chronic bitching and moaning that theres nothing new in general aviation.

While none of the airplanes these companies make rewrite the laws of physics, they do, in our view, represent substantial progress. Evidently, buyers agree for Cirrus has sold more 1000 SR20s and SR22s while Diamond has fielded about 200 DA40 Stars and 600 two-place DA20 Katana/Eclipse/Evolution models. Whats the secret? There isnt one, really. Just the right combination of savvy marketing, price and well-made airplanes. But how well made, one might reasonably ask. And what about the performance? To find out, we recently pitted a Cirrus SR20 against a Diamond DA40 Star to see how they compare across a range of parameters. How fast are they? How much do they carry? How do they handle? And more important, how do they stand up to the rigors of fly-a-day GA operations?

For that last question, we surveyed Cirrus and Diamond owners. Except for technical questions, we kept the factories out of this. No tarted up demos here, nor lunches at the country club paid for by the marketing department to knock the harsh edges off our observations.

What We Did
To our good fortune, one owner-Don Cislo, a Chicago-area business owner-happens to own both a Cirrus and a Diamond. A new pilot, Cislo bought his DA40 as a trainer and wanting something faster and more capable, he bought a Cirrus SR22 about a month before our research began. Obviously, an SR22 isnt an apples-to-apples comparison so we contacted another SR20 owner, Bill ONeill of Cary, North Carolina, for the level-playing-field flyoff. However, we interviewed Cislo at length for his impressions of dealing with the two companies.

For the flyoff comparison, we reviewed each aircrafts POH carefully and extracted relevant performance data. We then flew the airplanes to see how they measured up. Speaking of measuring, we also carefully inspected the cockpits and rear seats and size, comfort and ergonomics and we examined every square inch of the airframes to evaluate paint, fit and finish and cosmetic issues. Further, we contacted owners and the factories with specific concerns these inspections raised.

First, some background. The SR20 hit the market in 1999 following a gush of promotional fanfare by Cirrus at Oshkosh and other major shows dating back to 1994. Cirrus claimed the SR20 represented no less than the future of general aviation and offered a roll-out sticker of $130,000, a price-point no one expected them to achieve. They didnt. Typical SR20s these days invoice well north of $250,000, although these airframes are admittedly better equipped than anyone could have imagined when Cirrus first unveiled the proof-of-concept airframe in 1996.

Four years into the program, Cirrus sells more high-ticket SR22s than it does SR20s, which are best thought of as entry level aircraft, albeit sophisticated ones. As of mid-2003, Cirrus announced a new down-market VFR-only version of the SR20, the SRV, listing for $189,900, including the Avidyne Entegra Primary Flight Display. (All Cirrus aircraft now include the PFD; steam gauges are history, except for back-up.)

Diamond debuted the DA40 Star in 2000 after one of the shortest developmental cycles in recent GA history. The Star is best described as a minimal four-place aircraft that builds on Diamonds success with the DA20 Katana/Eclipse/Evolution series. Its more modest than the SR20 in speed and price but carries about the same load so the two are certainly apples-to-apples as market contenders. Currently, a typical well-equipped Star sells for $235,000 with all-electric steam gauges and Garmin mapcomms.

Diamond recently announced that the Star will be available with the Avidyne Entegra for a base price of $228,800 and next year, it will also be sold with Garmins G1000 PFD.

As of late 2003, Diamond says more than 230 Stars are flying. In one of the bolder market initiatives, Diamonds follow-up product will be its diesel-powered DA42 Twin Star rather than a bigger, heavier single. The Twin Star will compete with the Cirrus step-up model, the SR22.

The Basics
Although both the Star and SR20 are composite aircraft, thats about all they share in basic design philosophy. The Star shows Diamonds origins as both a European manufacturer and a builder of sleek sailplanes. For instance, the Stars wings are two-piece affairs that can be demated by a couple of guys in under an hour-sailplane style-while Cirrus favors a massive, one-piece wing that has drawn the ire of shops charged with recovering an SR20/22 after an off-field arrival or a crash.

Both aircraft have stout, single-piece fuselages made from a pair of halves bonded together during assembly. Similarly, wings are built up from clamshell halves bonded together after all the innards have been installed. Diamond uses a wet layup composite method in which resin is applied by computer control during construction while Cirrus uses a more conventional pre-impregnated cloth construction method, some layed over foam core. Carbon composite is used in the cabin doors and the oil access door.

On the Diamond, everything is composite, including control surfaces, while Cirrus uses conventional riveted aluminum for control surfaces.

In our view, Diamonds composite work-whether by method or experience-is crisper than that on the Cirrus. In inspecting several airplanes carefully, we noted that Diamonds seams are flawless and fit items such as doors and fasteners have cleaner edges. Sighting the paint surfaces and lines on Don Cislos SR22 in oblique light revealed some flat spots and dimpling in the control surfaces, something we couldnt find in the Star. Cislo also pointed out some microscratching and overspray on his month-old SR22.

Rather than conventional doors, the Star has a forward-hinged bubble canopy and a quirky hatch for entry to the rear seat while the Cirrus has a forward swinging door on each side of the fuselage. While we like the idea of dual doors, neither airplane has what we consider the ideal design. The Diamond canopy could be a distinct liability for emergency egress if the airplane flips on its back although, admittedly, this hasnt been a real issue with the Katana and the Stars rear hatch has a release for emergency exits.

The SR20s forward swinging doors arent the best either, in our view. Because they rotate forward and upward, the doors could also be pinned in the event of a roll over and in normal use, they are somewhat awkward to manhandle closed, especially if youre parked with a tailwind.

In general, were not sure Cirrus has figured out the door thing just yet. The latch/handle is positioned too far aft on the door and requires a clumsy sideways twist to secure. Further, we encountered-and owners confirm-that both the SR20 and SR22 have occasional troubles with poorly fitting and difficult-to-secure doors. Cirruss Ian Bentley admits that its hard to defend the door design as the airplanes best feature but insists the doors will fit correctly if properly rigged.

In contrast, the Stars canopy and hatch close with a precise and satisfying ker-chunk. On the canopy, beefy pins and a double-action latch secure the canopy with no hint of air leaks. From the seated position, we found it a little easier to manipulate and close the Diamond canopy securely the first time than the Cirrus doors.

Ingress, Cabin Comfort
Getting into the Diamond at all takes practice; doing it elegantly isnt on the agenda. You enter the cockpit from forward of the wing, via a single step, then step into the cockpit by leading with one leg. Using the stout canopy hinge as a handgrip, you can then lower yourself into the seat on a sort of butt-first controlled trajectory. Those with stiff backs will struggle. The Cirrus is a bit better. You can enter from either side from behind the wing, then step into the cockpit without much effort. We think the Cirrus wing walks are about two inches too narrow; the flaps intrude too far inboard for a wider walk.

On the other hand, rear seat passengers have it better in the Diamond. Rather than crawling around a seat than doesnt pitch far enough forward in the Cirrus, Star passengers have their own hatch and its large enough to step right into cabin without undue contortion. The downside of the hatch is that the latch will tattoo your noggin if youre not careful when walking along the wing.

Once inside, the Cirrus cabin is more spacious, front and back. It is, after all, a bigger airplane. In the Star, the front cabin offers 43 1/2 inches of shoulder room versus 47 3/4 in the Cirrus. In the rear, the Diamond is 43 1/2 inches wide versus 46 1/2 inches for the Cirrus. That doesnt sound like much difference but in terms of comfort, we would say the Cirrus approaches Cadillac standards while the Diamond is more sports sedan. Both have comparable head room but Cirrus occupants have more leg room up front and more knee room, thanks to a sweeping panel and glareshield. (In newer Stars, Diamond has redesigned the lower panel to provide more knee room. More panel improvements are planned.)

The seat comfort winner is the Cirrus. We found them larger and more adjustable than those in the Star, although Diamond has recently improved the seats and they are by no means uncomfortable. Its just that the Cirrus seats are better, in our view. The Cirrus has four-point shoulder harnesses that are a cut above what you expect to find in even a luxury car while the Diamond uses three-point harnesses.

Neither Cirrus nor Diamond has aced cabin ventilation, in our view. The Cirrus has only low-mounted Wemac-type eyeball vents for both front and rear passengers. These are barely adequate on a hot, sunny day. During taxi, the doors can be opened and stout gas springs hold them up into the breeze, like a couple of spinnakers on a sailboat. The Diamond has enormous vents in the front panel plus overhead eyeball vents for passengers.

These are desperately needed on a hot day when flying into the sun because that bubble canopy is like a personalized greenhouse. Diamond has tinted the canopy and added a shaded area up top but the occupants need all the air they can get. The front vents are effective but terribly noisy; even with noise canceling headsets, they roar like banshees.

Both panels are well designed, in our view, but the Cirrus is less cluttered and easier on the eyes. With no sticks or yokes to obstruct the view, the Cirrus panel feels like its yards away, adding to the spacious feel of the cockpit. In earlier models, the panel is dominated by a single multi-function display, with steam gauges for the pilot or, in later models, the Avidyne Entegra PFD. Switches are nicely grouped on a shelf in front of the pilot and other controls, heater, vents, flaps and so on, are easily at hand. The fuel switch and gauging are on a center console along with throttle and mixture controls.

What the Cirrus is missing is a manual trim wheel. Manual trim would clearly improve its flyability, in our estimation; the electric-only trim option is a significant shortcoming.

The Diamond has a trim wheel nicely located on its center console and is more pleasant and precise to trim. For the DA40, Diamond picked Lycomings 180-HP IO-360, a fuel injected version of this engine family that wasnt in common use until Cessna began installing it in the revitalized Skyhawk. Its a relatively efficient four-cylinder with a good service history and few maintenance bugaboos. In the Diamond version, its a conventional three-lever system with a controllable pitch prop that we think is a good match for the airplane. As we go to press, Diamond has announced a fixed-pitch, carbureted version for the trainer market.

The heavier Cirrus needed more power so Cirrus picked Continentals IO-360-ES, a 200-HP six-cylinder power plant. It too has a controllable pitch prop-a two- or three-blade Hartzell-but no prop lever. RPM is controlled automatically by throttle position using a cam arrangement on the power lever. Eliminating the RPM lever was done in favor of operating simplicity but having flown the Cirrus models several times, we view it as an undesirable compromise. Its fine for takeoff, but in cruise, you often want to tweak the RPM this way or that to find a sweet spot for vibration or economy. Unfortunately, with the Cirrus system, you cant do that. In the SR22, we noted an unpleasant vibration signature which couldnt be tuned out by varying RPM.

Control circuitry in both is conventional in that they use combinations of cable and tubes to move ailerons, rudder and elevator, with either anti-servo tabs (Diamond) or a spring cartridge (Cirrus) for trimming.

The Cirrus has the much vaunted side controller on each cockpit wall while the Diamond uses a conventional center stick, one for each front seat. The Cirrus controller has a coolie-hat trim control for roll and pitch trim and PTT while the Diamond stick sports the PTT, autopilot controls and trim.

Which is better? Potatoes and pahtahtoes, if you ask us. Cirrus owners rave about the side controller being precise and natural but we find it tiring on the wrist, especially when maneuvering or doing multiple landings. It takes a hefty tug in the final phase of landing.

We much prefer the Diamonds center stick, which is long enough to provide plenty of leverage for control forces that are on the light side to begin with. But the side controller is far superior in one aspect: it opens up the cockpit to the extent that you can place charts and lapboards anywhere. Its like flying IFR in an easy chair. Diamonds center stick makes this frustratingly impossible.

Instrumentation in the SR20 is a moving target. It was introduced first with steam gauges and an ARNAV multi-function display which, frankly, wasnt up to the quality of the airplane design itself, in our opinion. Cirrus dropped the ARNAV display in favor the Avidyne EX5000 large-screen MFD and shortly thereafter began offering the Avidyne Entegra PFD as standard equipment. Mapcomms are Garmin 400 series combinations.

The latest version of the Entegra offers a sophisticated power, fuel and engine management package that features easy-to-read eye-popping graphics. Some Cirrus airplanes have a Century 1000 HSI-an annoying maintenance trouble spot, say owners-while others have the Sandel EHSI.

The current DA40 is rather more modest, with steam gauges on the left side and a Vision MicroSystems VM1000 combined engine gauge and monitor unit on the right side. As we go to press, Diamond is busy certifying both the Avidyne Entegra and the new Garmin G1000 PFD for the Star, which should be available sometime in 2004. The G1000 will also be standard equipment in Diamonds new DA42 Twin Star.

Both Diamond and Cirrus have wisely made their aircraft all electric, rather than relying on the venerable but troublesome dry vacuum pump to power gyro instruments. The Cirrus has a dual-alternator, dual buss/battery arrangement while the Diamond uses a clever alkaline battery pack to run a secondary gyro and lights in the event of an alternator or buss failure. In our view, both airplanes represent a giant leap forward in instrument reliability.

Performance, Handling
In a nutshell, the SR20 is faster than the DA40-at least at low and mid-altitudes-has about the same useful load but has greater range thanks to larger fuel tanks. In the DA40s favor, it has a better initial climb rate-by about 100 FPM-and is a markedly better short-field performer than the Cirrus. One interesting bit of data: when the U.S. Air Force Academy was shopping for a cadet introductory trainer, one test required accelerating to rotation speed and then stopping within 3500 feet. With its higher weight and power loading, the SR20 required 3478 feet for this test while the Diamond did it in 2158 feet.

We found puzzling that SR20 owners report widely varying cruise speeds. We asked owners to tell us what speed and power settings they use for typical cruise. These yielded responses all over the map, from 140 knots at 70 percent power to 130 knots at 65 percent to 150 knots at 65 percent power and 10 GPH, lean of peak.

Several owners complained that the SR20 is slower than Cirrus claims it is but owners are still overwhelmingly satisfied with the SR20s cruise speed, according to our survey. When we tested Bill ONeills year-old SR20, we recorded 150 knots at about 10.5 GPH, lean of peak. We conclude that anyone buying an SR20 should think of it as a 150-knot airplane, give or take 3 knots.

DA40 owners seem to report more uniform cruise speeds in the 130- to 135-knot range at between 9 and 10 GPH, depending on lean state. A few owners claimed as much as 145 knots, but we dont think thats a fair assessment of the airplane. Our test of Don Cislos DA40 at DuPage, Illinois yielded 134 knots at 65 percent power and 3000 feet. The highest speed we saw was 138 knots at just over 10 GPH and 5500 feet. Bottom line: the DA40 is a 130 to 135 knot cruiser.

As for handling, we like the control feel in the Cirrus. We like the Diamond better. Cirrus control forces are well harmonized, although theres a bit of breakout feel when rolling left or right from centered stick. Whats most noticeable about the SR20 is how solidly it maintains and returns to a trimmed airspeed with no hunting during power changes or when the stick is disturbed. Slow flight is relatively benign right into the stall, which is gentle and has to be provoked with determination.

In our view, however, the Diamond has nicer control feel, with more precise trimming-theres a manual wheel, as noted-and gobs of elevator authority thats available at the flick of a wrist right into deep slow flight, which the Star does better than the Cirrus.

We found that the Cirrus wants a hard tug for nose up, especially during landing and especially because its CG trends toward the forward limit. Speaking of landing, we think the Diamond is far easier-and more fun-to land than the SR20. The Diamond is comfortable down to 60 knots at light weights and will plop down in a satisfyingly short stretch of runway. Landings are so satisfying, that 30 minutes of touch and goes is a real hoot in the DA40.

In contrast, with higher wing loading, the SR20 needs more pavement, a faster approach speed and what we find to be an odd, nearly flat touchdown picture. The SR20 may be a simpler airplane to fly than other aircraft but its not easier to land, in our view. We would rate its landing characteristics as closer to a Mooney than a Cessna. Learnable, yes, but not as easy as the DA40. We think this aspect of the Cirrus design could stand improvement.

Safety
Both Diamond and Cirrus deserve major kudos for thoughtful design elements that both reduce the likelihood of crashes and that protect the occupants if a crash does happen. Cirrus worked with NASA to develop a crashworthy cabin, energy absorbing seats and fuel lines and tanks that are well protected by stout composite structures. Further, the absence of center control wheels or sticks and the pilots considerable distance from the panel should greatly reduce the likelihood of injury in the event of a crash.

Cirrus also uses a wing thats less likely to spin in the event of an inadvertent stall and, of course, theres the parachute. When all else fails, the CAPS parachute is designed to lower the aircraft to the ground at a survivable 1600 FPM descent rate.

Cirrus hasnt sugar-coated what a touchdown under the parachute would be like: occupants may be killed or injured, says the POH. Yet in the only successful deployment of the CAPS in anger-an incident in October 2002 near Dallas following the loss of an SR22s aileron in flight-the pilot emerged barely shaken after landing in scrub trees. The aircraft was relatively undamaged and has been made flyable again.

Diamond has undertaken similar safety initiatives in the DA40, although it has no airframe parachute and, as noted, the bubble canopy represents a minor egress risk in the event of a roll-over accident. Second, the Diamond has center sticks which emerge between the pilots legs. Although seatbelt restraint in the DA40 is excellent, the sticks are, nonetheless, uncomfortably close to a male pilots…ummm, cherished possessions. Otherwise, the Diamond has excellent crash space in the cockpit and its fuel system is well armored against post-crash fire.

On paper, the Cirrus seems to enjoy the safety edge, if you accept that the CAPS is a good idea. But the reality couldnt be more stark. Although Diamond has more than 200 DA40s flying, we cant find a single accident on which to base a judgment of its safety record. In other words, it has a perfect safety record.

On the other hand, the SR20, with 300 flying, has suffered nine crashes worldwide, four with fatalities, not to include the fatal crash of a pre-production test aircraft. Some in the industry say that every new type has a spate of accidents during its introductory period. But if thats true, why hasnt Diamond had its share?

Is the SR20 or Cirrus in general somehow snakebit? We doubt it but given the nature of these accidents-virtually all avoidable and caused by poor pilot judgment-we are increasingly of the opinion that Cirrus aircraft require more training than many owners may believe.

Further, we wonder if the Cirruss unique safety attributes-highly sophisticated instrumentation, crashworthiness, ease of operation and, of course, the parachute-attract marginally qualified pilots who just arent the sort who will seek ongoing training or who dont belong in the airplane in the first place.

To its credit, Cirrus does offer a 2 1/2 day factory approved training program that were told is much improved over its initial efforts. Diamond offers both an on-site factory approved training course or fly-to training from a company instructor.

Conclusion
So which is the better airplane of the two? As noted in our scorecard on page 5, the Cirrus comes out ahead when we add up everything.

In our view, the Diamond would easily best it except for three factors we consider important for the U.S. market: speed, range and cabin size. Even at 150 knots, the SR20 is a barely adequate go-places airplane, which explains why Cirrus has sold more SR22s. The DA40, at 135 knots or so, is just too slow, in our view.

We live in a big country here and although a 450-mile range is plenty in Europe, we want a little more in the U.S. (The Stars long-range tank option helps.) Last, the Cirrus has a more comfortable and spacious cabin than the Diamond does and you dont pay for that in a hugely higher cost, slower speed or significant difference in fuel burn.

Weve heard Cirrus fans denigrate the DA40 Star as toylike but Cirrus has lessons to learn from Diamond, in our view. Among all the airplanes weve flown, the Star is the one to beat for good handling and just plain fun flying. And as far as were concerned, based on our research, Diamond leads the industry in fit and finish and quality control issues. Well be curious to see how they apply that expertise to the new DA42 Twin Star.

For now, we think Cirrus enjoys the leg up over the Diamond; theyve earned it.


Also With This Article
Click here to view “Score Card.”
Click here to view “How Fast, How Far, How Much Stuff?”
Click here to view “Specifications Compared.”