Cirrus Design has made a revision to the wing design of its SR20 four-seater, to lower stall speeds and help improve lateral control up to and throughout stall conditions. President Alan Klapmeier says that the move is aimed to make "dramatic" improvements in general-aviation (GA) safety.
The relatively late change, which involves a leading edge extension outboard and a slight increase in camber, will mean a delay in certification until late 1997.
"It's worth it if we can keep people from losing control that way. We think there's a possibility it will have a slight impact on cruise speeds [now 160kt (300km/h)], but we will gain a big safety benefit. Our reputation will be based on safety, and we think we can dramatically change the levels of that in general aviation," adds Klapmeier.
The increased camber will give the outboard wing section a slightly lower stalling speed, "-so, if the root of the wing is really stalled, the pilot can still control the aeroplane," says Klapmeier.
"Certification and production are our first priorities," he adds, saying that construction work on the company's two new manufacturing sites at Grand Forks, North Dakota, and Duluth, Minnesota, begins in earnest in October. Wings and tails will be made at Grand Forks initially, with fuselage production and final assembly at Duluth. "We're aiming to make one aircraft a day, with around 250-300 a year eventually," he adds.
Cirrus is almost halfway through a process of converting 110 deposits from $2,500 refundable commitments to $15,000 non-refundable deposits.
Klapmeier also reveals that Cirrus is studying a "more basic version" of the SR20, dubbed the SRX. The aircraft would be a "fleet version for university flight schools and fixed-based operators", he adds. The SRX would be "an ideal demonstrator or rental aircraft". "It will be based on the same type certificate," says Klapmeier, who expects to receive the go-ahead around mid-1997. Cirrus has also selected Hartzell and Trimble as suppliers to the SR20. Hartzell will provide its two and three-bladed "scimitar"-design propellers. The aluminum blades have swept leading edges and, despite their small diameters (1.93m for the two-bladed and 1.88m for the three), they have a low noise signature.
Trimble has been named as primary avionics supplier and will provide a new, fully integrated package, including its 2000 Approach Plus global-positioning system certificated for instrument flight rules, two 760-channel communications transceivers, a navigation receiver, transponder and altitude encoder.
Source: Flight International
