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Historical Review
Excerpt from Sandia Report SAND85-1180
"An Introduction to Deployable Recovery Systems"
by Jan Meyer
August 1985
The first known
written account of a parachute concept is found in da Vinci's notebooks (cl495).
The sketch he drew consisted of a cloth material pulled tightly over a rigid
pyramidal structure. Although da Vinci never made the device, he is given credit
for the concept of lowering man to the earth safely using a maximum drag
decelerator.
Fauste
Veranzio constructed a device similar to da Vinci's drawing and jumped from a
tower in Venice in 1617. Over a century would pass before further developments
would be made by the famous balloonists, Joseph and Jacques Montgolfier. In 1783
they succeeded in lowering animals to the ground from rooftops or balloons.
During the same year Sebastian Lenormand jumped from a tower using a 14-foot
diameter parachute. The first emergency use of a parachute was made by Jean
Pierre Blanchard in 1785 after the hotair balloon he was in exploded. Blanchard
also worked on a foldable silk parachute, for until then all parachutes were
constructed with a rigid frame.
In 1797, Andrew Garnerin made the first jump with a parachute without a rigid
frame. One of Garnerin's balloon jumps from 8000 feet, a very high altitude for
the time, was observed by a French astronomer, Lalandes. As the parachute
descended, severe oscillations were induced in the canopy. Lalandes suggested
cutting a small hole near the apex of the canopy to inhibit the oscillations.
This modification is now known as the vent and does indeed dramatically reduce
canopy oscillations.
During the next century, parachute use was confined to carnivals and
daredevil acts. Acrobats would perform stunts on a trapeze bar suspended from a
descending parachute. The parachute was released from a hot-air balloon by
attaching the top of the parachute to the equator of the balloon with a cord
that broke after a person jumped from the basket. Public opinion became very
unfavorable towards the use of parachutes when Robert Cocking fell to his death
in 1837. Cocking jumped an inverted coneshaped parachute (point down) from 5000
ft. and distinguished himself by becoming parachuting's first fatality.
The next major contribution to parachute systems was the development of a
harness by Captain Thomas Baldwin in 1887. The concept of folding or packing the
parachute in a knapsak-like container was developed by Paul Letteman and
Kathchen Paulus in 1890. Kathchen Paulus also demonstrated an intentional
breakaway. After a first parachute inflated, it was released and pulled open a
second parachute.
The first jump from an airplane has been claimed by both Grant Morton and
Captain Albert Berry in 1911 or 1912. Morton jumped with a silk parachute folded
in his arms which he threw out as he left the plane. Captain Berry had a 36 ft.
parachute packed into a metal case beneath the fuselage. The parachute had a
trapeze bar for him to hold on to as he jumped and descended to the ground. Also
in 1911, an Italian, Pino, invented the pilot chute or drogue chute.' He
attached a small parachute with a rigid frame to his helmet. The pilot chute
would easily inflate, pull the helmet off and then pull the parachute out into
the airstream.
The first freefall jump was made by Georgia "Tiny" Broadwick in
1914, but the military still did not believe that the human body could tolerate
the experience of freefall for more than a few seconds before "blacking
out." The skeptics were convinced in 1919 by Leslie Irvin and Floyd Smith.
They demonstrated freefall jumps and developed the ripcord at the parachute
testing and training center at Wright Field, established in 1918.
From World War I to the early 1930's, conventional round silk (now known as
solid cloth) parachutes remained unchanged in structure. They were primarily
used by military air corps in Europe, Russia, and the United States. During the
1930's Germany's Luftwaffe established the essential ingredients for air
supremacy. Kurt Student conceived and implemented a rapid deployment strike
force by parachuting men, equipment, and weapons from gliders and aircraft, such
as the Junker JU52/3m. Germany demonstrated the effectiveness of airborne troops
delivered to the battle scene by parachutes during World War II.
The development of modern parachutes deployed at high speeds and high
altitudes started in the 1930's. Knacke and Madelung developed the ribbon
parachute in Germany for
decelerating heavy high speed payloads. After World War 11 Knacke invented the
ring slot parachute which is used for moderate subsonic speeds. This parachute
is used primarily for cargo delivery and aircraft deceleration. The ring slot
parachute is significantly cheaper to manufacture than the ribbon parachute. The
ring sail parachute, developed by Ewing, is used to decelerate payloads at low
to moderate subsonic deployments speeds. The ring sail parachute was used as the
final stages of the Mercury, Gemini, and Apollo projects because of its slow
inflation rate and stability.
H. G. Heinrich invented the guide surface parachute (left) used as a pilot chute
or for vehicle stabilization in the supersonic (to Mach 3) deployment regime.
The hyperflo parachute (right) developed by Sims, is used as a hypersonic pilot
chute for the Mach 1 to Mach 5 speed domain. The specific construction details
of these modern high speed parachutes may be found in the Recovery Systems
Design Guide.
The development of sport parachutes beyond solid cloth parachutes began in the
early 1960's. Solid cloth parachutes were modified with drive slots that provide
greater stability and horizontal speed. A class of sport parachutes, known as
high performance rounds, includes Piglets, Paracommanders, Sierras, and Papillon
parachutes. Piglets are similar to modified solid cloth parachutes, but are
constructed from less porous material than solid cloth parachutes. Piglet
parachutes are much smaller and much more reliable than solid cloth parachutes.
The other three high performance rounds are characterized by many modifications
in the form of turning and drive slots. The top of the canopy, or apex, is
pulled closer to the payload by means of additional rigging lines. These
parachutes are also known for their relatively high malfunction rate.
During the early space projects, Rogallo developed a single membrane flexible
wing, known as the parawing. The large parawings designed for recovery of
reentry vehicles did not have reliable opening characteristics at high speeds
and were not used in the actual manned flights. There are several review
articles describing the subsonic deployment and control of parawings. The
parawing parachute, designed for maximum lift as opposed to maximum drag, was
primarily used in sport parachuting during the 1970's.
By the late 1970's the parawing was replaced by the parafoil, invented in the
middle 1960's by Domina Jalbert, a kite maker. The parafoil or ram-air parachute
is a deformable airfoil that maintains its profile by trapping air between two
rectangularly shaped membranes, sewn together at the trailing edge and sides,
but open at the leading edge. Several ribs are sewn to the inside of the upper
and lower surfaces, maintaining an airfoil cross section in the spanwise
direction. Stabilizers are added to prevent side slipping. Most personnel
ram-air parachutes have a nominal aspect ratio of two and a forward speed of 25
to 30 mph. Dynamic stalls may be performed with a ram-air so that landings are
made with zero velocity. The ram-air may also be flown backwards by deflecting
the trailing edge past the stall configuration. The parawing and parafoil are
hybrids of maximum drag decelerators and rigid wing technology. The vastly
superior maneuverability of a ram-air parachute makes it one of the most
promising decelerators. The deployment of ram-air parachutes at high speeds
tends to degrade or destroy the parachute components. As suitable methods of
reefing and staging of deployment are developed the ram-air parachute may have
unlimited use.
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