45 Fun Facts About Helicopters

What supplies the lift and thrust for a helicopter?

Horizontally spinning rotors supply both lift and thrust, which is what lets a helicopter take off and land vertically, hover, and fly backwards and sideways where fixed-wing aircraft cannot.

From which language does the word 'helicopter' come?

The English word comes from French: Gustave de Ponton d'Amécourt coined hélicoptère in 1861 for his steam-powered model aircraft, and English adopted it soon after.

Which two Greek roots make up the word 'helicopter'?

Helix and pteron (spiral and wing) are the Greek roots; English speakers later rebracketed the word as heli- and -copter, which is why we say helipad and quadcopter.

What is the common US military slang for a helicopter?

Helo, pronounced 'hee-lo', is the everyday US military term for a helicopter, used throughout the Navy, Marine Corps and Coast Guard.

Which was the first successful, practical and fully controllable helicopter, in 1936?

The Focke-Wulf Fw 61 first flew on 26 June 1936 with twin side-by-side rotors on outriggers, and in 1937 set helicopter records for altitude, speed and endurance.

Which helicopter was the first to reach full-scale production, in 1942?

The Sikorsky R-4 first flew in January 1942 and became the first helicopter built in quantity; about 131 were delivered to US and British forces.

Which 1939 Sikorsky design became the template for modern helicopters?

The Sikorsky VS-300 first flew tethered on 14 September 1939; its single main rotor with a small anti-torque tail rotor became the layout most helicopters use.

What is the purpose of a helicopter's tail rotor?

The tail rotor counters torque: without it the fuselage would spin opposite to the main rotor, and the pedals vary its pitch to yaw the nose.

Which anti-torque system blows air along the tail boom to exploit the Coandă effect?

NOTAR stands for 'no tail rotor': a fan inside the boom pushes air out of slots so the Coandă effect and a direct jet thruster counter torque; Fenestron and FANTAIL are ducted fans.

What is a helicopter with intermeshing counter-rotating rotors called?

A synchropter has two intermeshing rotors on outward-tilted masts, geared so the blades never collide; the wartime Flettner Fl 282 Kolibri and the Kaman K-MAX use the layout.

How many flight control inputs does a helicopter pilot have?

Four inputs: the cyclic, the collective, the anti-torque pedals and the throttle, which together govern rotor-disk tilt, blade pitch, yaw and engine power.

Which control does a pilot raise to climb straight up from a hover?

The collective lever, beside the pilot's left hip, changes the pitch of every main rotor blade together; raising it increases lift so the helicopter climbs.

Where is the cyclic stick usually located?

The cyclic rises from the floor between the pilot's legs; it tilts the rotor disk to move the helicopter in a hover and acts like an aeroplane's stick in forward flight.

What is the throttle on most helicopters?

On most helicopters the throttle is a motorcycle-style twist grip on the end of the collective lever, used to hold rotor RPM within its narrow allowable band.

What is the emergency descent called when the rotor is turned by air rather than the engine?

In autorotation a freewheeling clutch lets the rotor disengage from a failed engine; upward airflow through the disk keeps it spinning so the pilot can flare and cushion the landing.

Which basic skill is widely regarded as the hardest for a student helicopter pilot?

Hovering is the skill students find hardest, because every correction on one control disturbs the other two and an inexperienced pilot can fall into pilot-induced oscillation.

Roughly what airspeed does a helicopter need to reach translational lift?

Effective translational lift arrives at roughly 16-24 knots, when the rotor flies out of its own downwash and gains lift without extra power; some heavy helicopters need it just to get airborne.

How fast does a typical main rotor turn?

A light helicopter's main rotor turns at roughly 300-600 RPM (a Robinson R22 runs about 530); the transmission gears the engine down, while the small tail rotor spins at 1,000-5,000 RPM.

Which helicopter became the world's first turbine-powered helicopter in December 1951?

The Kaman K-225 flew with a Boeing 502 turboshaft in December 1951, the first turbine helicopter; the Alouette II of 1955 became the first turbine helicopter built in quantity.

Which was the first helicopter certified for civilian use in the United States?

The Bell 47 received the first civil helicopter type certificate on 8 March 1946; developed from Arthur Young's Model 30, it stayed in Bell production until 1974.

Around what date did Chinese children first play with bamboo flying tops?

The bamboo-copter is spun by rolling a stick attached to a rotor; it inspired Western scientists into the 19th century.

What did Leonardo da Vinci call his 1480s vertical-flight design?

Leonardo's 'aerial screw' of the 1480s was a helical sail meant to bore upward through the air; his notes suggest small models, but nothing to stop the rotor spinning the whole craft round.

Which French inventor's rubber-band helicopter toy inspired the young Wright brothers?

Alphonse Pénaud designed the coaxial-rotor rubber-band toy in 1870; Milton Wright gave his sons one in 1878, and the boys later built larger copies of it.

Which new metal was d'Amécourt's 1861 steam helicopter model celebrated for using?

D'Amécourt's little steam model was celebrated as an innovative use of aluminium, then a newly available metal; it never lifted off, but the word he coined for it survived.

Which Italian pioneer's steam helicopter rose 13 metres over Milan in 1877?

Enrico Forlanini's unmanned steam-driven model climbed about 13 metres and stayed up roughly 20 seconds in 1877; Milan's Linate airport is officially named after him.

What did Thomas Edison try to power his 1885 helicopter engine with?

Edison made guncotton from stock-ticker paper to fuel an internal combustion engine for his helicopter; the explosions damaged the machine and badly burned a worker.

The 1907 Breguet Gyroplane No. 1 is possibly the earliest example of what?

It lifted a pilot about 0.6 m for a minute, but needed a man at each corner to steady it, so it was not a free flight.

Who made the first truly free helicopter flight with a pilot, on 13 November 1907?

Paul Cornu's twin-rotor machine rose about 0.3 m for 20 seconds near Lisieux on 13 November 1907 and later reached nearly 2 m, but it was too unstable and was abandoned.

Which engineer invented the autogyro, first flown successfully in 1923?

Juan de la Cierva's C.4 autogyro flew near Madrid in January 1923; he crossed the English Channel in one in 1928, and autogyros flew airmail between Camden and Philadelphia in 1939.

Which pilot demonstrated the Fw 61 inside Berlin's Deutschlandhalle in 1938?

Hanna Reitsch, Germany's star test pilot, flew the Fw 61 inside the Deutschlandhalle during the February 1938 Berlin motor show, a propaganda showpiece staged before thousands of spectators.

How many helicopters had Igor Sikorsky's company built by the end of World War II?

Over 400: the R-4 was followed by the R-5 and the R-6, which together took Sikorsky past 400 machines by 1945, far ahead of rival Platt-LePage, whose XR-1 flew in 1941.

What name does the US Army give the Sikorsky UH-60 utility helicopter?

The Sikorsky UH-60 Black Hawk entered US Army service in 1979 as the replacement for the UH-1 'Huey'; the Navy's SH-60 Seahawk is a derivative.

What is the use of helicopters to fight wildland fires called?

Helitack crews use helicopters against wildland fires, dunking helibuckets such as the Bambi bucket in lakes and rivers; the Erickson S-64 Aircrane is a common purpose-built helitanker.

How much does NASA's Mars helicopter Ingenuity weigh?

Ingenuity weighs just 1.8 kg (4 lb); its twin rotors spin at roughly 2,500 RPM, several times faster than an Earth helicopter, because Mars's air is only about 1% as dense.

Which is the largest helicopter ever to go into serial production?

The Mil Mi-26, NATO reporting name Halo, lifts up to 20 tonnes of payload; only the experimental twin-rotor Mil V-12 of 1968 was bigger.

Which helicopter set the FAI absolute speed record of 400.87 km/h in 1986?

Westland Lynx G-LYNX, flown by test pilot Trevor Egginton on 11 August 1986 with BERP rotor blades whose tips neared Mach 0.97, set the 400.87 km/h record over the Somerset Levels.

Which helicopter landed on the summit of Mount Everest in May 2005?

Didier Delsalle set an FAI-confirmed record by landing a stripped-down Eurocopter AS350 B3 on the 8,848 m summit on 14 May 2005, then landed there again the next day.

What rotor layout does the Boeing CH-47 Chinook use?

The Chinook's tandem rotors turn in opposite directions, cancelling torque so no tail rotor is needed; named for the Chinook people of the Pacific Northwest, it entered service in 1962.

What is the top speed of the CH-47 Chinook?

On its 1962 debut it was far faster than contemporary utility helicopters and remains one of the fastest in the US inventory.

Which company had the largest share of the in-service civil helicopter fleet in 2018?

Robinson's 24.7% narrowly edged Airbus Helicopters' 24.4% of the 2018 in-service civil fleet, with Bell at 20.5% and Leonardo at 8.4%.

What is the design airspeed limit of a helicopter called?

Beyond it the retreating blade can stall, causing severe vibration, pitch-up and a roll toward that side.

How many flights did NASA's Mars helicopter Ingenuity complete before its January 2024 retirement?

Ingenuity flew 72 times between April 2021 and January 2024, far beyond its planned five flights; rotor-blade damage on the final landing ended the mission.

Which Frenchman set the first FAI-recognised helicopter world record in April 1924?

Étienne Oehmichen's quadrotor flew 360 metres on 14 April 1924 for the first FAI-recognised helicopter record; four days later Raúl Pateras-Pescara beat it with 736 metres.

In which campaign did the Sikorsky R-4, the only Allied helicopter of World War II, mainly serve?

Burma: the USAAF 1st Air Commando Group flew R-4s on search and rescue there from April 1944, including the first helicopter combat rescue; total R-4 production reached 131.

Which Russian polymath showed a spring-powered coaxial rotor model to the Academy of Sciences in 1754?

Mikhail Lomonosov demonstrated his spring-driven coaxial-rotor 'aerodynamic' to the Russian Academy of Sciences in July 1754, modelled on the Chinese flying top and meant to lift meteorological instruments.