HelicoptersHelicopters

By: Loren Kanov

March 12, 2001

Honors Physics

Mr. Pagani Period 6

Table of ContentsTable of Contents

History of HelicoptersSignificant ContributionsIgor I. SikorskyHow it WorksHow it ManeuversResources

History of HelicoptersHistory of Helicopters

The ancient Chinese had toys that rose upward when spun rapidly.

Leonardo Da Vinci made drawings of what we now know as the helicopter.

The invention of the internal combustion engine made it possible to develop full-sized models with an adequate power source.

Significant contributionsSignificant contributions

1907: French pioneer Paul Cornu lifted a twin-rotored helicopter into the air entirely without assistance from the ground for a few seconds.

1924: French pioneer Etienne Oehmichen became the first to fly a helicopter one kilometer in a closed circuit. It took 7 minutes and 40 seconds.

1936: Spaniard Juan de la Cierva created the autogyro which was not a true helicopter, but reached new heights in vertical flight.

Igor I. SikorskyIgor I. Sikorsky Designed the world’s first true

production helicopter Greatly influenced in contemporary

science by his mother and father As a child, he built model aircraft and

helicopters Achieved international recognition in

1913 for designing and flying the first multimotor airplane

In late 1938, United Aircraft management approved his experimental helicopter and on Sept. 14, 1939, the VS-300 made its first flight

His single-rotor design remains the dominant configuration of helicopters today

How it worksHow it works

How it worksHow it works

Direction: The helicopter has two jet

turboshaft engines which turn the rotor blades

As the blades sweep through the air, they form what is called the “rotor disc”

The rotorhead, which is where the blades are connected, is controlled by a swash plate which transfers the pilot’s instructions to the rotor blades

By raising and lowering each blade at a precise point in its revolution, the pilot tilts the rotor disc in the desired direction

Control: A cyclic control stick tilts the rotor

disc in the desired direction and controls speed

The collective pitch lever connects to the swash plate and changes the pitch of the rotor blades in unison, enabling the helicopter to climb or descend

Foot pedals connected to the control arms on the tail rotor blades work together with the cyclic control stick to make right or left turns

How it worksHow it works

Lift: The rotor blades are shaped like the

wings of an airplane: curved on top and flat on bottom

When they rotate, the pressure of the slower-moving air flowing under the blade is greater than the faster-moving air above it

This difference in pressure pushes the blades up, giving the helicopter the lift it needs to fly

Balance: Without a tail rotor, the body of the

helicopter would be forced in the opposite direction of the spinning rotor blades

The tail rotor compensates for this by providing lateral thrust in the opposite direction, holding the body stationary

How it maneuversHow it maneuvers

Changing the angle or tilt of the helicopter’s rotor blades tells the aircraft whether to move forward or backward or to hover motionless in the air.

Forward

Hover

Backward

resourcesresources1. Bosing, Tom. “Computer Solutions: The Helicopter,” © 1996.Http://www.iao.com/howthing/htwheli.htmThis site describes the structure of a helicopter and explains how the helicopter works.

2. Lippi, Jonathan. “Igor I. Sikorsky,” © 1987. Http://www.invent.org/bok/book-text/96.htmlThis site gives a bibliography of Igor I. Sikorsky including background on his life andhis accomplishments.

3. McKee, George. “Helicopter History Site,” © 1998. Http://www.helis.comThis site discusses the history of helicopters dating back as far as the 1500's when thefirst helicopter models were made.

4. Nelson, Jay. “Discovery Center–How it Works: Helicopter Bacis,” © 2000.Http://www.utc.com/disciver/hiw-heli.htmThis site explains how a helicopter works and maneuvers in basic terms that make iteasy to understand.

1. Bosing, Tom. “Computer Solutions: The Helicopter,” © 1996.