Cirrus Design chief executive Alan Klapmeier says his company will file an application to certificate the Vision SJ50 single-engined jet with the US Federal Aviation Administration on 17 December, but will not undertake a parallel effort in Europe in the near term.
"We're not filing because we're not paying," Klapmeier says.
Klapmeier's issue centres on recent European Aviation Safety Agency rules that charge an applicant to certificate aircraft that weigh more than 1,999kg (4,410lb). Latest weight figures revealed by Cirrus show the Williams International FJ33-4A-19-powered jet has a maximum take-off weight of just over 2,720kg. The FAA does not as yet charge fees for certification services.
The company's decision to move ahead with formal certification in the US is buoyed by 120h of successful initial test flights with its V1 prototype aircraft. "We have yet to be surprised," says Mike Van Staagen, Cirrus vice-president for advanced development, noting that stability and control characteristics are matching what was predicted in windtunnel and computational fluid dynamics analyses.
Test pilots have so far mapped out the entire centre-of-gravity envelope, attained maximum and minimum speeds and performed in-flight engine restarts. Pilots are now mapping out the aircraft's slow-speed stall characteristics.
Lessons learned have yielded a production aircraft that will have "subtle" differences compared with the V1, says Van Staagen. The fuselage will be shortened to save weight and modified from a circular cross-section to add roominess. Cirrus also removed the right door and replaced it with an emergency hatch to save weight. For stability and control reasons, engineers swept the aircraft's V-tail forward and enlarged the ventral fin. Tests of a dual ventral fin are also under way.
By increasing the tailpipe cant angle from 6.5° to 12° upward, Cirrus has reduced the side-stick controller forces by 67% to hold the nose level during worst-case go-around thrust applications, says Van Staagen. The wingspan will remain at 11.7m (38.5ft), although engineers experimented with spans as wide as 13.7m.
Maximum cruise speed for the production aircraft will be slower than the 319kt (590km/h) achieved with V1, in part due to the tailpipe cant, but Cirrus promises at least a 300kt top speed and 1,850km (1,000nm) range with reserves. Klapmeier says the five-seat jet, likely to be priced at $1.25 million equipped, could be ready for deliveries in 2011.
The company did not clarify how long it will wait to begin EASA certification work, and Klapmeier is hopeful that US efforts to have the certification weight limit lifted will be successful.
Source: Flight International
