1940 to 1969
After the second world war, Europe especially needed
fresh designs to stimulate its war-shattered economy, and the Jodel 'Bebe'
single seater which could be built at home and which even on 25 hp was
capable of taking off from a large lawn, was almost ideal. So much so, that
it gave rise to a whole new family of truly light aircraft. But despite the
good intentions of its creators Edouard Joly and Jean Delemontez, the old
problem resurfaced. The aeronautical equivalent of a Sunday drive simply
didn't provide enough sales to survive on, and by the early '50s Jodel had
turned to the two-seater market, graduating from 65 to 75 and eventually to
80 hp. The power race had begun all over again!
There was one notable exception to this preference
for power and speed, the American gliding fanatic Volmer Jensen. However, we
are getting ahead of ourselves…
Curiously, it was astronautics which rekindled
interest in low-speed flight. The principal character in this re-awakening is
called Francis Melvin Rogallo, an American aeronautical engineer, in 1936,
this quiet character joined Langley Research Center at Hampton, Virginia, the
only government financed aeronautical research laboratory on that side of the
Atlantic. He left Langley in 1970 after 34 years of loyal service, retiring
to Kitty Hawk in North Carolina. There, in the very spot where the 'Wright
Flyer' began powered flight, Rogallo continued work on an invention which was
to revolutionise unpowered flight - the delta flexwing, or as we know it, the
Until Frances and his wife Gertrude Sugden patented
the first version of their flexwing in 1948, wings had always been designed
to be essentially rigid. Early designs used a lozenge-shape; then they
experimented with a triangle and finally came the classic Rogallo shape, a
delta wing. The trick is in the profile; the wing forms two half-cones and,
seen from behind, two half-cylinders. These are flexible fabric lobes which
inflate in flight, being attached to the nose and two leading edges of the
triangle, but left free at the trailing edge.
Meanwhile, Rogallo had been nominated director of
the Low Speed Vehicle branch of Langley. They were studying methods of
recovering the first stage of Saturn rockets after launching, and especially
the space capsules of the Gemini and Apollo programmes. Our man, naturally,
thought of using his flexwings as pilotable parachutes.
The military got involved: they asked Ryan
Aeronautical to design a system based on the Rogallo wing, and on 23 May
1961, NASA test pilot Lou Everett took off in the first Rogallo ever to leave
the ground under power, a prototype - using a Continental 0-200 100 hp light
aero engine simply called 'Flex-Wing'. A few months and several
disappointments later, the 'Flex-Wing' was tried again with a 180 hp
Lycoming, as a four-seater with a 1100 lb (500 kg) empty weight. This
attained the magnificent speed of 60 mph (97 kph) and only made up for it by
not stalling until 24 mph (39kph). It was followed by the 'Fleep' (a
contraction of 'Flex-Wing' and Jeep), which abandoned the simple rudder of
its predecessor in favour of an empennage and a keel. This was capable of
carrying 990 lb (450 kg) at 64 mph (103 kph) but used 220 hp! Next came the
'Flex Flyer' at the end of 1963, a side-by-side two seater with a canard.
With a 595 lb (270 kg) empty weight and a useful load of 282 lb (128 kg), it
was capable of 76 mph (122 kph). We must not forget the 'Flex Bee', the only
microlight of the lot.
With just 28 ft2 (2.6 m2) of wing area it carried 66
lb (30 kg) of TV cameras at 65 mph (105 kph) to more than 4900 ft (1500 m),
all on a 9.5 hp McCullock MC-40 engine - a machine with military potential
for remote-control reconnaissance.
The 'NASA Connection' also generated some false
starts, as a freight carrier towed behind a helicopter, as a precision
parachute, or as a folding wing mounted on ejection seats to allow American
'advisers' in Vietnam to regain the security of their own lines without
having to walk. Each test was as inconclusive as the others.
One of the first people to realise the fun potential
of Rogallo's creation was Californian Barry Palmer, who began building
Rogallos in 1961 and by 1969 was motorising them with first one chainsaw
motor, then two, and later with a 15 hp snow-mobile unit. But his efforts
remained a curiosity, rather than blossoming into a new sport. In fact the
link between the NASA work and the mainstream evolution of hang-gliding is
much less direct, and arose in a quite unexpected way - through water-skiing.
By the end of the '60s, the really passionate water
skiers were no longer content just to jump ramps. Since 1964 French champion
Bernard Danis had lifted off the water by harnessing himself to a kite behind
a powerful outboard. This had made some others envious, amongst them his
competitor and friend Bill Moyes.
Bill is an Australian aeronautical engineer who had
worked for NASA and knew about the disappointments experienced with Rogallo's
wings. On returning to Australia, he adapted one of these wings as a ski
kite, and in 1968 he made it controllable by adding the triangle of tubes
which was to become known as the trapeze or A-frame. The following year, at
the water skiing world championships in Copenhagen, Bill Moyes caused a
sensation: in flight, he released the cable attaching him to the outboard and
glided down to land on the water. Hang-gliding had been born.
Bernard Danis took Moyes' innovations back to France
and that September, together with Jean-Francois Moveau and Christian Raisin,
he effected the first hang-glider flights above the lake of Annecy.
Meanwhile, Moyes' partner Bill Bennett went to preach the word in the US. He
combined this with the national water-ski championships at Berkeley, and on 4
July, Independence Day, he started a flight around the Statue of Liberty. At first towed behind an outboard, he released the
cable, glided for a long time, and landed at the feet of the statue.