曝光台 注意防骗
网曝天猫店富美金盛家居专营店坑蒙拐骗欺诈消费者
Administration (NASA) development of the Rogallo wing
into the Paresev (Paraglider Research Vehicle) later renamed
the Parawing. That aircraft had rigid leading edges shown
in Figure 1-4. NASA had the cart attached to the keel hanging
below the wing and using weight shift to control the wing in
the same fashion as modern WSC aircraft today.
1-3
Figure 1-3. Rogallo’s flexible wing for a kite, submitted for patent
in 1948.
Figure 1-5. Barry Palmer flying a foot-launched hang glider in
1961.
Figure 1-4. NASA testing the Rogallo wing, which led to the modern
hang glider and WSC aircraft.
During this same period, other pioneering engineers and
enthusiasts started developing the Rogallo wing for sport. One
was aeronautical engineer, Barry Palmer, who saw pictures of
the NASA wings and, in 1961, constructed and fl ew a number
of hang gliders based on the Rogallo design. [Figure 1-5]
His efforts and others evolved to the WSC aircraft in the late
1960s. Another pioneer was John Dickenson of Australia
who used the NASA Rogallo wing design but incorporated
a triangular control bar that provided structure for the wing
during fl ight with fl ying wires. [Figure 1-6]
1-4
Flying Wires
Control Bar
Ground Wires
Figure 1-6. Simple structure added to the Rogallo wing allows wires to hold up the wings on the ground and support the wing in flight.
Figure 1-7. An original Rogallo wing, 1975.
Hang Glider
The WSC system and the good fl ying qualities of the Rogallo
wing and Dickenson wing, combined with its easy set-up
and portability, started the hang gliding craze in the early
1970s. [Figure 1-7] In 1967, the fi rst powered aircraft based
on the fl exible wing concept of Dr. Rogallo was registered
as amateur-built experimental. Flexible wing development
continued, and by the early 1970s several adventurous
entrepreneurs were manufacturing Rogallo wings for sport
use.
Another signifi cant step in wing design was an airfoil that
would change shape for optimum performance at slow and
fast speeds. It was the fi rst Rogallo wing with a lower surface
that could enclose the structure that holds the wings out.
Enclosing this cross bar tube and providing a thicker airfoil
similar to the airplane wing provided a jump in high speed
performance. This double-surface wing was quickly adopted
by manufacturers as the high performance standard and is
used on faster WSC aircraft today. [Figure 1-8]
Activity in the hang gliding community increased throughout
the 1970s, which resulted in the proliferation and development
of stable, high-quality modern hang gliders like the one
shown in Figure 1-9.
Motorized Hang Gliders
In the late 1970s, performance had increased enough to allow
motors to be added to hang gliders and fl own practically. It
was not until the wings had become effi cient and the engines
and propeller systems evolved that the fi rst commercial motor
for a hang glider was introduced in 1977, the Soarmaster. It
used a two-stroke engine with a reduction system, clutch, and
long drive-shaft that bolted to the wing frame. It had a climb
rate as high as 200 feet per minute (fpm) which was acceptable
for practical fl ight. However, during takeoff the wing would
overtake the running pilot, and launching was very diffi cult.
Also while fl ying, if the pilot went weightless or stalled under
power, the glider would shoot forward and nose down into
a dive. Overall, with the propeller pushing the wing forward
during takeoffs and in some situations while fl ying, this was
unsafe for a wide application. [Figure 1-10]
A Maturing Industry
Engines and airframe technology had made great advances
because the ultralight fi xed wing evolution was providing lighter
weight, higher power, and more reliable propulsion systems.
The propeller was moved lower for better takeoff and fl ight
characteristics, wheels were added, and the trike was born at
the end of the 1970s. A trike describes a Rogallo type wing
with a three wheeled carriage underneath (much like a tricycle
arrangement with one wheel in front and two in back). Trike
is the industry term to describe both ultralight vehicles and
1-5
Enclosed crossbar
Double or lower surface
Figure 1-8. The double-surface patented wing, 1978.
Figure 1-9. A modern high-performance hang glider soaring high
over the mountains from which it was launched.
Figure 1-10. First motorized system design sold as an add-on kit for a hang glider.
Engine
Propeller
Thrust at wing
Propeller guard
Propeller shaft
Light-Sport Aircraft (LSA) WSC aircraft. [Figure 1-11] The
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：
Weight-Shift Control Aircraft Flying Handbook(8)
