Steve Wilson argues that there are safety issues with Cirrus airplanes. First, Wilson feels that the Cirrus is more prone than your typical Beechcraft to crashes in which the pilot loses control of the aircraft while maneuvering. Second, Wilson feels that the Cirrus is more susceptible to crashes involving inadvertent encounters with icing conditions.
Of course, the NTSB chalks up both of these types of accidents to pilot error, not to a fault in the
aircraft. But as far as I’m concerned, the NTSB finds pilot error too often, frequently overlooking how the machine may have contributed to an accident. Certainly, not everyone agrees with me. But Wilson seems to.
A former NTSB-trained accident investigator myself, I assure you, prejudice during investigation is always to blame a pilot. There is inadequate focus on the aircraft. Investigation parties of small aircraft consist of an NTSB investigator, possibly an FAA Flight Standards Inspector (there to violate the pilot), manufacturer reps (there to defend the product); there is never a human factors expert.
Prone to Loss of Control Accidents
So what is it about the machine that may contribute to loss of control accidents? According to Wilson, it’s the design of the Cirrus’ flight controls.
The Cirrus control system offers no “feel”, very little aerodynamic resistance because its control mechanism is centered by springs, not by aerodynamic pressure. A Cirrus control in flight feels the same to a pilot at any airspeed. Furthermore, small hand movements command full flight control deflection. The Cirrus joystick is so touchy that Cirrus instructors teach pilots to squeeze the control handle instead of pull back to rotate at takeoff.
Wilson notes the industry recognizes unusual flight control response as a hazard in other aircraft such as the Zodiac. But while the NTSB has zeroed in on the troubled Zodiac, it has not looked into the Cirrus’ design at all. In fact, except for Wilson, few have linked Cirrus’ accident record to its flight control system. But Wilson doesn’t stand completely alone. Another flight instructor and Cirrus owner, Philip Greenspun, has made similar observations. According to Greenspun:
One problem with the Cirrus is its unforgiving handling compared to other basic four-seaters. For pilots accustomed to learning about an impending stall by feeling reduced airloads on the flight controls, the Cirrus provides much less stall warning. This is due to spring cartridges that continue to resist flight control movement even when the airplane is not moving.
Pilots refer to some aircraft as “honest airplanes.” A change in the "feel" of an honest airplane warns the pilot that he is approaching the edge of an envelope. If you ask me, the Cirrus’ spring cartridges mask much of that feedback, just as Wilson and Greenspun suggest. According to Wilson, the lack of control "feel" may account for the string of loss of control accidents involving highly experienced Cirrus pilots.
Especially Dangerous in Icing Conditions
Next, Wilson says the Cirrus is particularly dangerous when it encounters icing conditions. The Cirrus’ "laminar flow" wing is built for speed, not safety. Compared to other wings, it is more vulnerable to stalling when it is contaminated with ice. According to Wilson, while ice can bring down any aircraft, the Cirrus’ margin of safety is very small.
The design of Cirrus’ tail is also problematic, according to Wilson, because the elevator is susceptible to “ice bridging." In short, the elevator control can lock-up due to ice, making the airplane uncontrollable.
True, the aircraft isn’t certified for flight in icing conditions, and pilots are supposed to stay out of ice. But, Wilson says, if you inadvertently find yourself in icing conditions, the Cirrus’ design characteristics won’t afford you much of a chance to escape.
Cirrus Design will continue to lure pilots into situations that are beyond what reasonable skill level and human attention can be expected to handle. . . Be warned Cirrus pilots. You are at more risk than you may know.