What is a Gyroplane? What is a Gyroplane? "Gyroplane"
"Gyroplane" is an official term designated is an official term designated by the Federal Aviation Administrby the Federal Aviation Administrationation (FAA) des
(FAA) describing an aircraft that gets cribing an aircraft that gets lift from a freely lift from a freely turning rotary wing, or rotorturning rotary wing, or rotor blades, and
blades, and which derives its which derives its thrust from an thrust from an engine-driven propellerengine-driven propeller. Historically. Historically, this, this type of aircraft has been known as
type of aircraft has been known as the autogiro and the the autogiro and the gyrocoptergyrocopter. These early. These early names and their variants were filed as
names and their variants were filed as trademarks.trademarks. Gyroplanes derive lift from freely turning rotor blades
Gyroplanes derive lift from freely turning rotor blades tilted back to catch the tilted back to catch the airair. The. The rushing air spins the rotor as
rushing air spins the rotor as the aircraft is thrust forward by an engine-driventhe aircraft is thrust forward by an engine-driven propeller
propeller. Early gyroplanes . Early gyroplanes were powered by engines were powered by engines in a in a tractor (pulling)tractor (pulling) configuration and were relatively heavy. Modern gyroplanes use a
configuration and were relatively heavy. Modern gyroplanes use a pusher propellerpusher propeller and are light a
and are light and maneuverable. With the engine in the nd maneuverable. With the engine in the rearrear, the gyroplane has, the gyroplane has unobstructed
unobstructed visibilityvisibility..
Gyroplane - Helicopter
Gyroplane - Helicopter ComparisonComparison The Gyroplane
The Gyroplane
•
• Thrust is produced by an engine-driven propellerThrust is produced by an engine-driven propeller •
• The unpowered, freely turning rotor is tilted back The unpowered, freely turning rotor is tilted back as the gyroplane movesas the gyroplane moves
forward forward
•
• Oncoming airflow through the rotor causes it to Oncoming airflow through the rotor causes it to spin, producing lift. This isspin, producing lift. This is
called
called autorotationautorotation..
•
• Always operates in autorotation, thus:Always operates in autorotation, thus: •
• Cannot stall like fixed wing aircraftCannot stall like fixed wing aircraft •
• Flies safely at low altitudes Flies safely at low altitudes and low speeds, but cannot hoverand low speeds, but cannot hover •
The Helicopter The Helicopter
•
• The powered rotor produces both lift and thrust, and The powered rotor produces both lift and thrust, and is tilted forwardis tilted forward •
• Can hover, but a powered rotor requires:Can hover, but a powered rotor requires: •
• Adequate forward speed and/or altitude to maintain Adequate forward speed and/or altitude to maintain flight in case of flight in case of powerpower
failure failure
•
• A heavy main A heavy main transmissiontransmission •
• TTail rotor to ail rotor to counteract the torque imposed counteract the torque imposed on the aircrafton the aircraft
A Gyroplane can fly more slowly than airplanes and will not stall. They can fly faster A Gyroplane can fly more slowly than airplanes and will not stall. They can fly faster than helicopters but
than helicopters but cannot hovercannot hover. Since the . Since the rotor blades on trotor blades on the gyroplane arehe gyroplane are powered only by the air
powered only by the air (autorotation), much like a windmill, there is no (autorotation), much like a windmill, there is no need for aneed for a tail rotor for anti-torque. The gyroplane is a stable flying platform. This is not so with tail rotor for anti-torque. The gyroplane is a stable flying platform. This is not so with helicopters, which pull the air down through engine-powered rotor blades making helicopters, which pull the air down through engine-powered rotor blades making itit possible to hover
possible to hover, but , but also making the also making the aircraft very complicated and expensive to aircraft very complicated and expensive to flyfly.. Due to their inherent simplicity, gyroplanes are easier to operate and less expensive Due to their inherent simplicity, gyroplanes are easier to operate and less expensive to maintain than
to maintain than helicopters.helicopters.
Design Simplicity Design Simplicity
The simplicity of
The simplicity of a gyroplane's design translates directly a gyroplane's design translates directly into safetyinto safety, higher, higher performance, higher mission readiness, lower maintenance,
performance, higher mission readiness, lower maintenance, and more economicaland more economical operation for its operator.
Gyroplanes in flight are always in autorotation. If power fails in a gyroplane the Gyroplanes in flight are always in autorotation. If power fails in a gyroplane the autorotation continues, and the aircraft settles softly to
autorotation continues, and the aircraft settles softly to the ground from any altitude.the ground from any altitude. The procedure to land after
The procedure to land after a power failure is nearly the a power failure is nearly the same procedure as a normalsame procedure as a normal landing, which requires no landing roll. Thus the
landing, which requires no landing roll. Thus the gyroplane is a safer aircraft for lowgyroplane is a safer aircraft for low and slow flight, as compared with both helicopters and airplanes. The ability of and slow flight, as compared with both helicopters and airplanes. The ability of gyroplanes to fly faster than
gyroplanes to fly faster than helicopters and slower than airplanes makes ithelicopters and slower than airplanes makes it something of a hybrid, having the
something of a hybrid, having the good qualities of the other two good qualities of the other two types of aircrafttypes of aircraft with little of the bad.
with little of the bad. The single attraction of
The single attraction of helicopters over gyroplanes is their helicopters over gyroplanes is their ability to hoverability to hover, which is, which is necessary in some situations such as rescue or in
necessary in some situations such as rescue or in sling load work. In air surveillancesling load work. In air surveillance and point-to-point flying, not being able
and point-to-point flying, not being able to hover is not a dito hover is not a disadvantage becausesadvantage because many gyroplanes, such as the Groen Brothers Hawks, take off a
many gyroplanes, such as the Groen Brothers Hawks, take off a nd land verticallynd land vertically without having to
without having to hoverhover. Helicopters at . Helicopters at low altitude out low altitude out of ground effect avoidof ground effect avoid hovering whenever possible. It is
hovering whenever possible. It is too dangerous. Ttoo dangerous. To fix o fix surveillance on one spot,surveillance on one spot, proper procedure for all rotorcraft is to circle in
proper procedure for all rotorcraft is to circle in a slow orbit.a slow orbit. History of Gyroplanes History of Gyroplanes Excerpt From Excerpt From Autogiro to Gyroplane: 1923 - 2003 Autogiro to Gyroplane: 1923 - 2003 Dr. Bruce H. Charnov Ph.D. J.D. Dr. Bruce H. Charnov Ph.D. J.D. Hofstra University Hofstra University Juan de la
Juan de la Cierva was born in Murcia, Spain on September 21, 1895, Cierva was born in Murcia, Spain on September 21, 1895, and by 1908-9,and by 1908-9, had decided to make aviati
had decided to make aviation his careeron his career. In 1911 he enrolled at . In 1911 he enrolled at the Civil Engineeringthe Civil Engineering College of Madrid (Caminos, Canales y
College of Madrid (Caminos, Canales y Puertos) and in 1912 with his friends "Pepe"Puertos) and in 1912 with his friends "Pepe" Barcala and Pablo Diaz constructed the first Spanish a
Barcala and Pablo Diaz constructed the first Spanish a irplane, the BCD-I, known asirplane, the BCD-I, known as "EI Cangrejo" - the "Red Crab", becoming the
"EI Cangrejo" - the "Red Crab", becoming the "Father of Spanish Aviation.""Father of Spanish Aviation."
In 1919 Cierva produced a large three-engine bomber that, piloted by Captain Julio In 1919 Cierva produced a large three-engine bomber that, piloted by Captain Julio Rios Argiieso, crashed in its initial flight when the
Rios Argiieso, crashed in its initial flight when the aircraft stalled. Pondering theaircraft stalled. Pondering the
crash, Cierva's brilliant insight was to see the wing differently ---aircraft stalled when crash, Cierva's brilliant insight was to see the wing differently ---aircraft stalled when the air passing over the wing failed to generate enough lift at slow speed - he
the air passing over the wing failed to generate enough lift at slow speed - he reasoned that stall could be
reasoned that stall could be effectively eliminated if the wing itself effectively eliminated if the wing itself movedmoved independently of the
independently of the aircraft. The rotoraircraft. The rotor, a , a moving, stall-proof wing, was placed moving, stall-proof wing, was placed onon top of a fuselage. He patented the name" Autogiro" and it flew by autorotation, "the top of a fuselage. He patented the name" Autogiro" and it flew by autorotation, "the process of producing lift with freely-rotating aerofoils by means of t
process of producing lift with freely-rotating aerofoils by means of t he aerodynamiche aerodynamic forces resulting from an
forces resulting from an upward flow of airupward flow of air." As long ." As long as the Autogiro was as the Autogiro was propelledpropelled forward, air coming up through the rotor would generate lift,
forward, air coming up through the rotor would generate lift, and should theand should the Autogiro's motor fail, it would gently descend while
Autogiro's motor fail, it would gently descend while air flow upward through the rotorair flow upward through the rotor blades.
blades.
Between 1920 - 23 Cierva progressively developed autorotation in the C.1,
Between 1920 - 23 Cierva progressively developed autorotation in the C.1, C.2 andC.2 and C.3, but it would
C.3, but it would be his forth model that be his forth model that would finally conqueror the airwould finally conqueror the air. Cierva. Cierva stated that the first flight of his CA Autogiro was on January 9, 1923 at Getafe stated that the first flight of his CA Autogiro was on January 9, 1923 at Getafe airfield outside Madrid when (
airfield outside Madrid when ( Calvary) Lieutenant Alejandro G6mez Spencer guidedCalvary) Lieutenant Alejandro G6mez Spencer guided the craft in taxi tests
maintain that the first observed (and filmed) flight of C.4 took maintain that the first observed (and filmed) flight of C.4 took place on January 17, 1923
place on January 17, 1923 when G6mez Spencer flew 600 ftwhen G6mez Spencer flew 600 ft at a steady
at a steady height of 13 ft height of 13 ft across the field. Tracross the field. Transferringansferring operations to England in 1925 and
operations to England in 1925 and forming Cierva Autogiroforming Cierva Autogiro Ltd. on March 24,1926 with
Ltd. on March 24,1926 with prominent Scottish industrialistprominent Scottish industrialist James G. Weir, his brother Viscount William Weir of Eastwood James G. Weir, his brother Viscount William Weir of Eastwood and Sir Robert M.
and Sir Robert M. KindersleyKindersley, Cierva continued to , Cierva continued to improve theimprove the Autogiro and in early 1929 licensed the
Autogiro and in early 1929 licensed the technology and rightstechnology and rights to his patents to
to his patents to Harold Frederick Pitcairn of Bryn Athyn, P A.Harold Frederick Pitcairn of Bryn Athyn, P A. The youngest son of
The youngest son of John Pitcairn, co-founder of Pittsburgh Plate John Pitcairn, co-founder of Pittsburgh Plate Glass CompanyGlass Company,, Harold was born in 1897 and took an early interest in aviation. Inspired by the first Harold was born in 1897 and took an early interest in aviation. Inspired by the first flight of the Wright brothers in 1903, he began flight training as an air cadet in the flight of the Wright brothers in 1903, he began flight training as an air cadet in the last days of WWI, and would eventually earn a pilot's license signed by Orville last days of WWI, and would eventually earn a pilot's license signed by Orville Wright. Pitcairn and Agnew Larsen, who he had met
Wright. Pitcairn and Agnew Larsen, who he had met in pilot training, produced thein pilot training, produced the classic Mailwing airmail series, but it
classic Mailwing airmail series, but it was the Autogiro that fired their passion. Inwas the Autogiro that fired their passion. In 1928 Pitcairn ordered a Cierva C.8W (the
1928 Pitcairn ordered a Cierva C.8W (the W was for the American Wright WhirlwindW was for the American Wright Whirlwind engine), which arrived at Pitcairn Field, Willow Grove, PA and on
engine), which arrived at Pitcairn Field, Willow Grove, PA and on December 18, 1928December 18, 1928 made the first rotary-wing flight in America piloted
made the first rotary-wing flight in America piloted by Cierva pilot H. C. A. "Dizzy"by Cierva pilot H. C. A. "Dizzy" Rawson, followed the next day by Pitcairn.
Rawson, followed the next day by Pitcairn. In early 1929, Cierva and
In early 1929, Cierva and Pitcairn negotiators agreed that the Pitcairn-CiervaPitcairn negotiators agreed that the Pitcairn-Cierva Autogiro Company (PCA) would be formed in America with the rights
Autogiro Company (PCA) would be formed in America with the rights to licenseto license Cierva's patents. Pitcairn threw himself into the development and promotion of Cierva's patents. Pitcairn threw himself into the development and promotion of thethe
Autogiro - and the results of the
Autogiro - and the results of the next 16 months wouldnext 16 months would earnhim and his
earnhim and his associates the Collier Trophassociates the Collier Trophy for they for the
greatest aviation achievement for 1930. Pitcairn had refined greatest aviation achievement for 1930. Pitcairn had refined Autogiro development, first learning from the C8W (which Autogiro development, first learning from the C8W (which was presented to the Smithsonian on July 22, 1931), was presented to the Smithsonian on July 22, 1931), thenthen with a series of developmental aircraft, the PCA-I, 1A and lB. with a series of developmental aircraft, the PCA-I, 1A and lB. (The PCA-1A is currently exhibited at
(The PCA-1A is currently exhibited at the Americanthe American
Helicopter Museum & Education Center at the Brandywine Helicopter Museum & Education Center at the Brandywine Airport, West Chester, PA on loan from the Smithsonian). But Airport, West Chester, PA on loan from the Smithsonian). But it was the next
it was the next aircraft, the PCA-2, that captivated America. An original design theaircraft, the PCA-2, that captivated America. An original design the PCA-2 was seen over major American cities in late 1930-early 1931 in
PCA-2 was seen over major American cities in late 1930-early 1931 in its certificationits certification flights to much publicity and a
flights to much publicity and acclaim. It innovated with a clutched gearbox thatcclaim. It innovated with a clutched gearbox that briefly transmitted power to prerotate the rotor to
briefly transmitted power to prerotate the rotor to greatly shorten the takeoff run. Itgreatly shorten the takeoff run. It would prove a crucial contribution to Autogiro development.
would prove a crucial contribution to Autogiro development.
Cierva developed progressively more sophisticated designs with a means to tilt Cierva developed progressively more sophisticated designs with a means to tilt thethe rotor head and altering the pitch (angle) of each individual rotor blade, called
rotor head and altering the pitch (angle) of each individual rotor blade, called collective and cyclic control, and,
collective and cyclic control, and, making use of making use of Pitcairn's prerotatorPitcairn's prerotator, achieved a, achieved a "jump takeoff" capacity with the C19MkIV in "jump takeoff" capacity with the C19MkIV in 1931-32 The rotor would be spun up
1931-32 The rotor would be spun up at zeroat zero pitch and then "snapped" into a positive angle, pitch and then "snapped" into a positive angle, causing the aircraft to
causing the aircraft to "jump" into air"jump" into air, an, an ability developed by Pitcairn the next
ability developed by Pitcairn the next year inyear in the developmental PA-22 Autogiro. But both the developmental PA-22 Autogiro. But both inventors realized that this was only a
inventors realized that this was only a partialpartial step in realizing the
step in realizing the Autogiro's potential, for aAutogiro's potential, for a significant problem remained. Even though the significant problem remained. Even though the Autogiro could takeoff and
wing-based control surfaces lost effectiveness at slow landing speeds. Cierva's C30 wing-based control surfaces lost effectiveness at slow landing speeds. Cierva's C30 series and Pitcairn's PA-22 and Luscombe-built aluminum
series and Pitcairn's PA-22 and Luscombe-built aluminum body PA-36, and the KD-1body PA-36, and the KD-1 series constructed by Kellett Autogiro Company of
series constructed by Kellett Autogiro Company of Philadelphia were engineeringPhiladelphia were engineering marvels capable of jump take-offs and direct-control without wings. But this came marvels capable of jump take-offs and direct-control without wings. But this came too late to
too late to save the Autogiro, for the world's attention was riveted on the stunningsave the Autogiro, for the world's attention was riveted on the stunning indoor demonstrations of the
indoor demonstrations of the Focke-Focke-Achgelis Fa-61 helicopter by Hanna Reitsch inAchgelis Fa-61 helicopter by Hanna Reitsch in 1938.
1938.
Cierva died in the crash of a
Cierva died in the crash of a KLM DC-2 boundKLM DC-2 bound for Amsterdam from the airport at
for Amsterdam from the airport at CroydonCroydon Aerodrome, London on December 9, 1936. Aerodrome, London on December 9, 1936. Stripped of his passion, the Cierva Autogiro Stripped of his passion, the Cierva Autogiro Company
Company, under the , under the engineering leadership of engineering leadership of Dr. J.A.J. Bennett, would shift the focus of its Dr. J.A.J. Bennett, would shift the focus of its efforts towards developing a helicopter; and efforts towards developing a helicopter; and even though Cierva-licensed Autogiros would be even though Cierva-licensed Autogiros would be used by the British, French, Russian and
used by the British, French, Russian and Japanese forces, the Autogiro would all but Japanese forces, the Autogiro would all but disappear by the end
disappear by the end of WWII. Few would knowof WWII. Few would know or remember that it
or remember that it was the English Cierva Rota C.30A Autogiros that would dailywas the English Cierva Rota C.30A Autogiros that would daily calibrate the coastal radars that enabled the RAF to defeat the German Luftwaffe and calibrate the coastal radars that enabled the RAF to defeat the German Luftwaffe and win the Battle
win the Battle of Britain. The of Britain. The Japanese Kellett-licensed KayJapanese Kellett-licensed Kayaba Ka-1A Autogiro seriesaba Ka-1A Autogiro series had virtually no impact on
had virtually no impact on the war and the Russian TsAGI A7 Autogyro (not builtthe war and the Russian TsAGI A7 Autogyro (not built under a Cierva license, hence not an
under a Cierva license, hence not an Augtogiro), the first such aircraft specificallyAugtogiro), the first such aircraft specifically constructed for combat operations, faded before the might of
constructed for combat operations, faded before the might of the German onslaughtthe German onslaught as did the
as did the French aircraft built by Liore-et-Oliver and SNCASE.French aircraft built by Liore-et-Oliver and SNCASE. Almost no one
Almost no one remembers the obscure British Armed Forces Experimentalremembers the obscure British Armed Forces Experimental Establishment Malcolm Rotaplane or
Establishment Malcolm Rotaplane or RotabuggyRotabuggy, a , a modified Willys 1/4 modified Willys 1/4 ton "four-by-ton "four-by-four" military truck with a seesaw "teetering" rotor an
four" military truck with a seesaw "teetering" rotor an d attached aircraft controld attached aircraft control surfaces. Perhaps the most ungainly
surfaces. Perhaps the most ungainly flying craft everflying craft ever, it , it was towed successfully towas towed successfully to 1,700 ft. And even less well-known was "Project Skywards", a parallel wartime 1,700 ft. And even less well-known was "Project Skywards", a parallel wartime attempt in Australia to develop a
attempt in Australia to develop a flying jeep ("Fleep").flying jeep ("Fleep").
The most familiar of the WWII autorotational The most familiar of the WWII autorotational developments were, paradoxically, the most developments were, paradoxically, the most
insubstantial, the English and German rotary kites. insubstantial, the English and German rotary kites. The Focke-Achgelis FA-330, launched from German The Focke-Achgelis FA-330, launched from German submarines at the end of a 400 ft tether to increase submarines at the end of a 400 ft tether to increase target observation, is found in more museums than target observation, is found in more museums than any other comparable craft only because the Allies any other comparable craft only because the Allies captured the factory
captured the factory, but few of , but few of the 1943 Englishthe 1943 English Rotachutes designed by Raoul Hafner survive, a Rotachutes designed by Raoul Hafner survive, a one-person giro-glider designed to insert secret agents person giro-glider designed to insert secret agents into occupied Europe from airplanes with a
into occupied Europe from airplanes with a precisionprecision gained from use of a two-bladed teetering rotorhead that could be controlled by gained from use of a two-bladed teetering rotorhead that could be controlled by means of a hanging-stick control.
means of a hanging-stick control.
And so by the end of WWII the Autogiro had effectively disappeared. Pitcairn had And so by the end of WWII the Autogiro had effectively disappeared. Pitcairn had surrendered his airfield to the military
surrendered his airfield to the military for wartime use and had the for wartime use and had the prototype PAprototype PA-36-36 aluminum bodies cut up for scrape to
aluminum bodies cut up for scrape to aid the war effort. Kellett had aid the war effort. Kellett had renamed itself renamed itself the Kellett Aircraft Company and
becoming briefly the
becoming briefly the Firestone Glider & Autogiro Firestone Glider & Autogiro CompanyCompany, was effectively out , was effectively out of theof the business. The other American licensee,
business. The other American licensee, the Buhl Aircraft Companythe Buhl Aircraft Company, had , had developed adeveloped a single model but failed
single model but failed to survive the Depression. And the attempts by to survive the Depression. And the attempts by Philadelphia’sPhiladelphia’s E. Burke Wilford, making use of patents
E. Burke Wilford, making use of patents of Germans Walter Rieseler and Walterof Germans Walter Rieseler and Walter Kreiser (rigid rotors with control achieved by means of cyclic pitch
Kreiser (rigid rotors with control achieved by means of cyclic pitch variation) had notvariation) had not gained engineering acceptance. And perhaps the most i
gained engineering acceptance. And perhaps the most i ntriguing autorotationalntriguing autorotational
experiments, the pioneering convertiplane combination of a gyroplane and fixed-wing experiments, the pioneering convertiplane combination of a gyroplane and fixed-wing aircraft of Gerard P
aircraft of Gerard P. Herrick ended in . Herrick ended in 1942, but not 1942, but not before successful mid-airbefore successful mid-air conversions by test pilot George
conversions by test pilot George TTownson in 1937 ownson in 1937 (that aircraft, the Herrick HV-2A is(that aircraft, the Herrick HV-2A is stored at the
stored at the Paul Garber CenterPaul Garber Center, Silver Hill, , Silver Hill, MD). In 1945 MD). In 1945 Dick Haymes may haveDick Haymes may have crooned to Helen Forrest in I'll Buy That
crooned to Helen Forrest in I'll Buy That Dream that "we can honeymoon in Cairo inDream that "we can honeymoon in Cairo in our brand new Autogiro" but there were no new
our brand new Autogiro" but there were no new Autogiros - it seemed certain thatAutogiros - it seemed certain that Cierva's vision would merely be a minor footnote to
Cierva's vision would merely be a minor footnote to helicopter development, but ithelicopter development, but it did survive -- it came
did survive -- it came down to a single Rotachute and a down to a single Rotachute and a Russian immigrant - IgorRussian immigrant - Igor Bensen. Although Harris Woods would design and fly a giro-glider in 1945, a Bensen. Although Harris Woods would design and fly a giro-glider in 1945, a development unknown to Bensen and
development unknown to Bensen and forgotten by historyforgotten by history, the popular , the popular future of future of autorotation lay with the charismatic, passionate Russian!
autorotation lay with the charismatic, passionate Russian! Igor Bensen, born in 1917, was the
Igor Bensen, born in 1917, was the son of a Russian agricultural scientist, Basilson of a Russian agricultural scientist, Basil Mitrophan and Alexandra P
Mitrophan and Alexandra P. Bensen. His father . Bensen. His father was posted to was posted to CzechoslovCzechoslovakia in akia in 19171917 at the beginning of
at the beginning of the Russian Revolution while the rest of the fathe Russian Revolution while the rest of the fa mily remainedmily remained behind. The Russian civil war lead to
behind. The Russian civil war lead to harsh times, and the Bensen family harsh times, and the Bensen family was soonwas soon reunited in Prague, far from the turmoil.
reunited in Prague, far from the turmoil. At 17 Bensen was sent to the At 17 Bensen was sent to the University of University of Louvain in Belgium, from which he received a
Louvain in Belgium, from which he received a B.S. degree.B.S. degree. Bensen accepted a scholarship from the Stevens Institute in
Bensen accepted a scholarship from the Stevens Institute in New Jersey in 1937 toNew Jersey in 1937 to study mechanical engineering, graduating with honors in 1940. As an
study mechanical engineering, graduating with honors in 1940. As an alien Bensenalien Bensen had been forced to
had been forced to turn down a job offer to work for turn down a job offer to work for Igor SikorskyIgor Sikorsky, and his first job, and his first job was as an engineer with
was as an engineer with General Electric at the age of General Electric at the age of 23. General Electric executives23. General Electric executives took notice of Bensen's interest and assigned the
took notice of Bensen's interest and assigned the young engineer to the company'syoung engineer to the company's helicopter development efforts.
helicopter development efforts.
While working on the project, Bensen flew a
While working on the project, Bensen flew a salvaged Kellett XR-3 in 1943, andsalvaged Kellett XR-3 in 1943, and eventually gained almost exclusive use of the surplus Autogiro. Bensen became a eventually gained almost exclusive use of the surplus Autogiro. Bensen became a highly skilled Autogiro pilot, and gained a deep understanding of the dynamics and highly skilled Autogiro pilot, and gained a deep understanding of the dynamics and theory of autorotational flight. The USAAF had
theory of autorotational flight. The USAAF had received some of the recovered FAreceived some of the recovered FA--330 rotary kites and were experimenting with
330 rotary kites and were experimenting with pilot George Tpilot George Townson, as well as aownson, as well as a Hafner Rotachute and Bensen asked his boss to acquire the
Hafner Rotachute and Bensen asked his boss to acquire the Rotachute for evaluation.Rotachute for evaluation. The military agreed to
The military agreed to loan the Rotachute providing that General Electric agreed notloan the Rotachute providing that General Electric agreed not to fly it.
to fly it.
Bensen ignored the military's requirements and personally flew the
Bensen ignored the military's requirements and personally flew the Rotchute in tow,Rotchute in tow, and launched it from the
and launched it from the bomb rack of the XR-3. Those testsbomb rack of the XR-3. Those tests
lead to the Bensen B-1, an amateur-built 120 Ib giro-glider capable of carrying a 300 lead to the Bensen B-1, an amateur-built 120 Ib giro-glider capable of carrying a 300 Ib load, differing from thee Rotachute with the addition of nose and tail wheels, a Ib load, differing from thee Rotachute with the addition of nose and tail wheels, a semi-rigid rotor in place of the
semi-rigid rotor in place of the Rotachute's individual flapping rotor blades, and aRotachute's individual flapping rotor blades, and a control stick 'reverser' to allow
control stick 'reverser' to allow more effective direct-control of the rotormore effective direct-control of the rotor. The . The crash of crash of the B-1 led directly t
the B-1 led directly to the B-2 which was of an o the B-2 which was of an all-metal construction. The B-2 leadall-metal construction. The B-2 lead to the G-E Gyro-Glider in
to the G-E Gyro-Glider in NovemberNovember, 1946 but little , 1946 but little came of the G-E model. came of the G-E model. AndAnd subsequently in Schenectady
subsequently in Schenectady, the Helicraft , the Helicraft Equipment Company developed a 60 Equipment Company developed a 60 IbIb variant of the Rotachute called the Heli-glider in
that flew with a 14 ft rotor that achieved 550 rpm, the lack of weight made it
that flew with a 14 ft rotor that achieved 550 rpm, the lack of weight made it difficultdifficult to fly with an
to fly with an overhead stick control, and the project was soon abandoned.overhead stick control, and the project was soon abandoned.
Benson, now firmly committed to rotary flight development, joined Kaman Aircraft in Benson, now firmly committed to rotary flight development, joined Kaman Aircraft in 1951 where he organized and di
1951 where he organized and directed the research department and flew Air Forcerected the research department and flew Air Force and Navy
and Navy helicopters. After two years, borrowing money from helicopters. After two years, borrowing money from his brotherhis brother, Bensen, Bensen left to found his
left to found his own company in Raleigh, NC.own company in Raleigh, NC. In 1953 Bensen
In 1953 Bensen Aircraft Corporation introduced the B-5 Gyro-GliderAircraft Corporation introduced the B-5 Gyro-Glider, a , a single-seatsingle-seat rotary--kite towed in back of a vehicle and
rotary--kite towed in back of a vehicle and deriving its lift from an deriving its lift from an unpowered rotorunpowered rotor.. It featured a
It featured a light tubular aluminum frame resembling a cross with two light tubular aluminum frame resembling a cross with two pieces, apieces, a longer keel crossed by a shorter perpendicular section. A lightweight longer keel crossed by a shorter perpendicular section. A lightweight aluminum-frame web set was attached to both the keel and a reinforced metal mast extending frame web set was attached to both the keel and a reinforced metal mast extending upward from the keel. Control was initially achieved with
upward from the keel. Control was initially achieved with a hanging stick controla hanging stick control attached directly to the rotor hub that was positioned on top of the mast with a attached directly to the rotor hub that was positioned on top of the mast with a two-blade rotor
blade rotor. A nose wheel was attached . A nose wheel was attached directly to the front of the directly to the front of the keel while landingkeel while landing wheels were affixed to each end
wheels were affixed to each end of the perpendicular crosspiece. The keel, in back of of the perpendicular crosspiece. The keel, in back of he seat and mast, carried a plywood fin and rudder much as had the Rotachute. It he seat and mast, carried a plywood fin and rudder much as had the Rotachute. It flew well when towed by even a small automobile and did not require any license, flew well when towed by even a small automobile and did not require any license,
and was relatively safe. It
and was relatively safe. It was alsowas also
distinguished by ease of construction and distinguished by ease of construction and the builder could either purchase a kit or the builder could either purchase a kit or build from plans. The materials were readily build from plans. The materials were readily obtained and fabrication could be completed obtained and fabrication could be completed by the moderately skilled in 3-4
by the moderately skilled in 3-4 weeks. Itweeks. It would become the home-built B-6, and the would become the home-built B-6, and the prototype was accepted into the
prototype was accepted into the
Smithsonian's NASM on July 22, 1965. Smithsonian's NASM on July 22, 1965. Bensen subsequently developed a
Bensen subsequently developed a ReynoldsReynolds aluminum prototype, the B-7 Gyro-gilder which flew on June
aluminum prototype, the B-7 Gyro-gilder which flew on June 17, 1955. From B-717, 1955. From B-7 .came the B-7M (for motorized) which first flew on
.came the B-7M (for motorized) which first flew on December 6,1955 with Bensen asDecember 6,1955 with Bensen as pilot and Charles "Charlie" Elrod and
pilot and Charles "Charlie" Elrod and Tim Johnson as ground crew. It weighed 188 lb.Tim Johnson as ground crew. It weighed 188 lb. as the airframe was made of
as the airframe was made of rounded aluminum tubing and had a rounded aluminum tubing and had a wooden propellerwooden propeller attached to a 42 hp Nelson two-stroke engine, with the wooden rotor attached to a attached to a 42 hp Nelson two-stroke engine, with the wooden rotor attached to a spindle type tilting head
spindle type tilting head cyclic pitch rotor with a hanging control stick. Bensen calledcyclic pitch rotor with a hanging control stick. Bensen called his Rotachute-derived creation a
his Rotachute-derived creation a GyrocopterGyrocopter, a , a term he term he subsequently trademarked.subsequently trademarked. After three days of successful flight testing the
After three days of successful flight testing the B-7M crashed as its pressurized fuelB-7M crashed as its pressurized fuel tank failed. Bensen, a
tank failed. Bensen, a highly experienced Autogiro pilot, set the aircraft down inhighly experienced Autogiro pilot, set the aircraft down in woods adjacent to his NC
woods adjacent to his NC factoryfactory. He later ascribed the . He later ascribed the safe landing to "much lucksafe landing to "much luck and the good Lord's will."
and the good Lord's will." The B-7M, rebuilt in three days, The B-7M, rebuilt in three days, was flying by Decemberwas flying by December 17, 1955, a particularly
17, 1955, a particularly moving experience for Benson as that was the 52ndmoving experience for Benson as that was the 52nd
anniversary of the Wright brothers first powered flight.. Ever aeronautical engineer anniversary of the Wright brothers first powered flight.. Ever aeronautical engineer and pragmatic scientist, Bensen relentlessly analyzed the flight performance of the and pragmatic scientist, Bensen relentlessly analyzed the flight performance of the B-7M, particularly those factors that had led to the accident, and the result was an B-7M, particularly those factors that had led to the accident, and the result was an improved control linkage to the rotor head.
The subsequent B-8M model, incorporating the improvements developed and tested The subsequent B-8M model, incorporating the improvements developed and tested in the B-7M, powered by
in the B-7M, powered by a more powerful 72 hp a more powerful 72 hp McCulloch two-stroke piston engineMcCulloch two-stroke piston engine that had been used
that had been used on drones for the military, was placed into production in 1957on drones for the military, was placed into production in 1957 and became the most produced and copied
and became the most produced and copied aircraft design in history and provided, in kit aircraft design in history and provided, in kit form and plan-built, the most popular way to form and plan-built, the most popular way to fly
fly. The "Spirit of Kitty . The "Spirit of Kitty Hawk", a B-8MHawk", a B-8M Gyrocopter in which Bensen had personally Gyrocopter in which Bensen had personally duplicated the Wright brothers historic first duplicated the Wright brothers historic first flight at Kitty Hawk on December 17, 1966, flight at Kitty Hawk on December 17, 1966, and with which he had set twelve world and and with which he had set twelve world and national Gyrocopter speed, distance and national Gyrocopter speed, distance and altitude records between May 1967 and altitude records between May 1967 and JuneJune 1968, was accepted into the
1968, was accepted into the SmithsonianSmithsonian Institution aviation collection on May 14, Institution aviation collection on May 14, 1969. The Bensen, and its
1969. The Bensen, and its variants and localvariants and local adaptation was to dominate the American adaptation was to dominate the American Gyrocopter movement for
Gyrocopter movement for almost twenty-fivealmost twenty-five years.
years.
In Europe,
In Europe, howeverhowever, it , it was a was a different storydifferent story. England's Wing . England's Wing Commander Kenneth H.Commander Kenneth H. Wallis, Scotland's Jim Montgomerie in
Wallis, Scotland's Jim Montgomerie in and Finland's Jukka Tervand Finland's Jukka Tervamaki began withamaki began with Bensen kits or plans, but soon modified
Bensen kits or plans, but soon modified the design,the design, taking gyrocopter design into
taking gyrocopter design into some very un-Bensen-some very un-Bensen-like directions. Wallis, who would achieve
like directions. Wallis, who would achieve international fame with "Little Nellie",
international fame with "Little Nellie", a WA-116a WA-116 autogyro, in the 1967 James Bond film
autogyro, in the 1967 James Bond film YoYou Only Liveu Only Live T
Twice, remains an wice, remains an honored pilot, world record holderhonored pilot, world record holder and designer, while Tervamaki did pioneering work and designer, while Tervamaki did pioneering work with composite materials (fuselage and rotor blades) with composite materials (fuselage and rotor blades) and was the most significant influence on Italy's and was the most significant influence on Italy's premier designer/ manufacturer Vittorio Magni. premier designer/ manufacturer Vittorio Magni.
But all mid-century-on attempts to revive the But all mid-century-on attempts to revive the Autogiro failed - in 1959-60 Kellett attempted Autogiro failed - in 1959-60 Kellett attempted bring its aircraft back for agricultural uses to no bring its aircraft back for agricultural uses to no avail, and the Pitcairn license of its
avail, and the Pitcairn license of its 1936 AC-351936 AC-35 "Rotadable" Autogiro, capable of driving down "Rotadable" Autogiro, capable of driving down the highway at 25-30 mph (stored today at the highway at 25-30 mph (stored today at thethe NASM Paul Garber facility) by Indiana's Skyway NASM Paul Garber facility) by Indiana's Skyway Engineering got no further than a
Engineering got no further than a prototype inprototype in the early 1960s. The most ambitious realization the early 1960s. The most ambitious realization of Cierva's vision, the Fairey Rotodye produced of Cierva's vision, the Fairey Rotodye produced under the initial
under the initial direction of Dr. direction of Dr. J.A.J. Bennett J.A.J. Bennett and Captain A. and Captain A. Graham Forsyth, flew between 1957 -1962 until Graham Forsyth, flew between 1957 -1962 until cancelled by the British government in its
cancelled by the British government in its "rationalization of the helicopter industry". The "rationalization of the helicopter industry". The
Rotodyne, a Rotodyne, a convertiplane convertiplane
making use of four 50
making use of four 50 ft steel jet-tipped rotors,ft steel jet-tipped rotors, could take off and land as a helicopter and fly as a could take off and land as a helicopter and fly as a gyroplane carrying 42 persons at 200 mph
gyroplane carrying 42 persons at 200 mph - in 1957- in 1957 with a perfect safety record. In
with a perfect safety record. In order to conceal theorder to conceal the amount of its funding, the
amount of its funding, the only model was orderedonly model was ordered destroyed by the British government and all that destroyed by the British government and all that remains of this incredible aircraft are a few parts in remains of this incredible aircraft are a few parts in a museum, photographs and films - had it gone into a museum, photographs and films - had it gone into production and the USMC pursued its interest, the production and the USMC pursued its interest, the military might have acquired an effective vertical/ military might have acquired an effective vertical/ fixed-wing combination that even now remains unrealized. And the Kamov Ka-22 fixed-wing combination that even now remains unrealized. And the Kamov Ka-22 (The "Russian Rotodyne"), known in the Soviet Union as the Vintokrulya (Vintokryl) (The "Russian Rotodyne"), known in the Soviet Union as the Vintokrulya (Vintokryl) ("Screw Wing"), and dubbed "Hoop" by NATO, also failed to gain government
("Screw Wing"), and dubbed "Hoop" by NATO, also failed to gain government acceptance after several crashes. And the Umbaugh (later Air & Space)
acceptance after several crashes. And the Umbaugh (later Air & Space) 18A, Avian18A, Avian 2/180 and McCulloch J-2 2/3 place
2/180 and McCulloch J-2 2/3 place gyroplanes failed to achieve commercialgyroplanes failed to achieve commercial acceptance despite technical sophistication and the enthusiastic belief of acceptance despite technical sophistication and the enthusiastic belief of theirtheir backers that the world needed a
backers that the world needed a gyroplane. In general, all that remained gyroplane. In general, all that remained of Ciervaof Cierva and Pitcairn's autorotational vision were the thousands of
and Pitcairn's autorotational vision were the thousands of amateur-built Gyrocoptersamateur-built Gyrocopters and their variants.
and their variants.
Bensen and his associates would in 1962
Bensen and his associates would in 1962 found the Popular Rotorcraft Associationfound the Popular Rotorcraft Association (PRA), which even today remains the world's preeminent Autogiro / auto gyro (PRA), which even today remains the world's preeminent Autogiro / auto gyro // Gyrocopter / gyroplane organization. Bensen declared in 1970 somewhat unfairly Gyrocopter / gyroplane organization. Bensen declared in 1970 somewhat unfairly that Ken Brock had so modified the design that it could not no longer be called a that Ken Brock had so modified the design that it could not no longer be called a Gyrocopter - Brock then called his KB2
Gyrocopter - Brock then called his KB2 a "gyroplane." Under Brock's presidency of a "gyroplane." Under Brock's presidency of the PRA (1972 -1987) gyroplane design
the PRA (1972 -1987) gyroplane design flourished. The most notable of the newflourished. The most notable of the new designers was Californian Martin Hollmann. His major contributions include the designers was Californian Martin Hollmann. His major contributions include the Sportster
Sportster, the , the world's first successful two-seat world's first successful two-seat amateur-built gyroplane trainer inamateur-built gyroplane trainer in 1972, and the first "ultralight" gyro plane, the "Bumble Bee", in 1983. Also
1972, and the first "ultralight" gyro plane, the "Bumble Bee", in 1983. Also
significant was Bill Parsons two-seat Trainer, a Bensen B-8M with a longer keel to significant was Bill Parsons two-seat Trainer, a Bensen B-8M with a longer keel to accommodate a second seat, dual controls and a rotor head attached by an accommodate a second seat, dual controls and a rotor head attached by an upside-down "u" shaped tandem double mast. But it was only at the start of a new century down "u" shaped tandem double mast. But it was only at the start of a new century that the Autogiro was to
Groen Brothers Aviation, headed by brothers David and Jay Groen, has
Groen Brothers Aviation, headed by brothers David and Jay Groen, has developed adeveloped a family of larger Hawk 4
family of larger Hawk 4 gyroplanes targeted to the agricultural, law enforcement,gyroplanes targeted to the agricultural, law enforcement, package delivery and passenger shuttle service markets. Time magazine, in package delivery and passenger shuttle service markets. Time magazine, in itsits November 19, 2001 issue, named the
November 19, 2001 issue, named the Hawk 4 as one of Hawk 4 as one of the best "Inventions of thethe best "Inventions of the Year."
Year."
The Utah Olympic Public Safety Command The Utah Olympic Public Safety Command
(UOPSC) made use of a Hawk 4 during the 2002 (UOPSC) made use of a Hawk 4 during the 2002 Olympics with a FLIR
Olympics with a FLIR Systems, Inc. day / nightSystems, Inc. day / night observation system, a Spectrolab Inc.
observation system, a Spectrolab Inc. SX-5SX-5 search light, an
search light, an Avalex TAvalex Technologies flat panelechnologies flat panel display
display, a , a Broadcast Microwave ServicesBroadcast Microwave Services realtime video downlink system and a law realtime video downlink system and a law enforcement communications radio stack. GBA enforcement communications radio stack. GBA had succeeded in defining a
had succeeded in defining a reconnaissancereconnaissance mission where Cierva, Pitcairn, Kellett, the mission where Cierva, Pitcairn, Kellett, the French, English, Germans, Russians, Japanese French, English, Germans, Russians, Japanese and even Ken Wallis had failed. Given the and even Ken Wallis had failed. Given the enthusiastic reception of the Hawk series of enthusiastic reception of the Hawk series of
gyroplanes, the business acumen of the Groen brothers and
gyroplanes, the business acumen of the Groen brothers and their associates, it istheir associates, it is likely that they will
likely that they will be successful and the Autogiro, in its newest gyroplanebe successful and the Autogiro, in its newest gyroplane configurations, will achieve an acceptance that has been elusive since the
configurations, will achieve an acceptance that has been elusive since the PCA-2 andPCA-2 and C.30A flew over American and European skies.
C.30A flew over American and European skies.
Groen Brothers Aviation extends their gratitude to Groen Brothers Aviation extends their gratitude to
Dr. Bruce H. Charnov for permission to share Dr. Bruce H. Charnov for permission to share the proceeding excerpt from his informative the proceeding excerpt from his informative
book “From Autogiro to Gyroplane.” book “From Autogiro to Gyroplane.”
