Aircrafts

Types and Construction

Nikhilesh Vaidya,

T.Y.

Instrumentation Engg.,

S.G.G.S.I.E.&T., Nanded.

What is an Airplane?

Aircraft

More general term

Refers to any heavier-than-air object that is

Supported by its own buoyancy

Supported by the action of air on its structures

Airplane

Heavier-than-air craft propelled by an engine

Uses aerodynamic surfaces (wings) to generate lift

What is an Airplane?

Every airplane is an aircraft, but not every aircraft is an airplane.

Space shuttle

Gliders

Helicopters

Types of Aircraft

Aircraft are categorized according to their intended purpose.

There are three common categories, they are:

General Aviation

Commercial Aviation

Military Aviation

General Aviation

General aviation includes those used for training, business and agricultural.

Aircraft in this category generally hold less than 12 passengers.

Commercial Aviation

This category includes commuter, cargo, and Firefighting aircraft.

Usually hold in excess of 20 passengers.

Military Aircraft

Military aircraft include Cargo, Fighter, Bomber, trainer, and special mission.

A-attack

B-Bomber

C-Cargo

F-Fighter

H-Helicopter

K-Refueling Tanker

O-Observation

S-Surveillance

T-Trainer

U-Utility

V-Vertical Take-off

X-Experimental

Military Aviation Helicopters

Helicopters are rotary wing A/C ranging in size from single seat to 50 passenger.

Some carry loads in excess of 10 tons.

Fuel capacities range from 70-1000 gal.

Internal fuel tanks are usually located under the cabin floor.

Auxiliary fuel tanks are located in the aft section or attached to the outside of the cabin

Military Aviation Helicopters

Helicopters are constructed mainly of Aluminum, Magnesium, Titanium, and composites.

Hazards included:

Rotor blades which can dip to 4’ of the ground

The tail rotor which can be nearly invisible when spinning.

Approaching from uphill or carrying objects above the waist.

Military Aviation Helicopters

Safety around Helicopters:

Always approach in sight of the pilot

Approach when pilot gives signal

Approach from downhill if possible.

Carry objects horizontally below waist

Maintain sufficient clearance for the main rotor and tail rotor, Clear the ground around the A/C for at least 50’ the the helipad.

Types

Jet fighters

Relatively lightweight

Highly maneuverable and very fast

Carry small amount of weight, including fuel

Must refuel on long flights

Passenger airplanes

Larger, carry more weight, fly longer distances

Less maneuverable and slower

More Types

Twin-engine

Sport plane

Turboprop

Cargo plane Business jet

Single-engine

A. Fuselage

B. Wings

C. Empenage or Tail

D. Power Plant

E. Landing Gear or

Undercarriage

Aircraft Components

Propeller

Landing Gear

Wing

Left Aileron

Fuselage

Empennage

Nacelle

Right Aileron

WingHorizonta

l Stabilizer

Vertical Stabilizer

Rudder

Elevator

Fuselage

Main body structure All other components are attached to it

Contains Cockpit or flight deck

Passenger compartment

Cargo compartment

Generally constructed in two or more sections

Carries accessories and other equipments

Includes numerous access doors, inspection plates,

landing wheel wells, and other openings

Wings

Most important lift-producing part of the aircraft

Also carries the fuel

Designed so that the outer tips of the wings are higher than where the wings are attached to the fuselage Called the dihedral

Helps keep the airplane from rolling unexpectedly

Wings

Wing Designs

Straight Wing Found mostly on small, low-

speed airplanes

Good lift at low speeds

Not suited to high speeds

Creates a lot of drag because the wing is perpendicular to the airflow

Provides good, stable flight

Cheap and can be made lighter

Wing Designs

Sweepback

Used on most high-speed airplanes

Less drag, but more unstable at low speeds

Amount of sweep depends on the purpose of the airplane

Commercial airliner has moderate sweep

High speed airplanes (e.g., fighters) have moderate sweep

No forward sweep wings are in mass production

Wing Designs

Delta Wings

Looks like a large triangle from above

Can reach high speeds

Landing speeds are very fast

Wing shape found on the supersonic transport Concord

Empennage

Also known as the tail assembly

Provides stability and control

Two main parts Vertical stabilizer (fin) to

which the rudder is attached

Horizontal stabilizer to which the elevators are attached

Power Plant

A unit or machine that converts chemical energy contains in

the fuel to thrust force. Thrust force is essential for moving

the airplane forward and producing lift force. With the piston

engine, the propeller is used to convert torque at engine shaft

to be thrust. With the jet engine, the jet engine output is the

thrust force.

Undercarriage

Also known as the landing gear, which is made up of

Struts

Wheels

Brakes

Can be fixed or retractable

Located underneath of the

fuselage with shock strut

Fixed / Retractable

Tri- cycle –Conventional type

Floating gear for seaplane /ski-

equipped for ice surface landing etc..

Landing Gear

Controls

Instruments and Controls

Supply information

Altitude

Direction

Provide control

Steering in the air and on the ground

Engine power

Braking

Black box

- High Strength to Weight

ratio

- Light weight

- Corrosion Resistant

- Should be non flammable

- High quality

• STEEL & ITS ALLOYS (Strong )

• ALUMINIUM & ITS ALLOY

(Commonly use)

• TITANIUM ALLOYS (Heat Barriers)

• MAGNESIUM ALLOYS (3 times lighter

than AL)

• PLASTICS & COMPOSITE MATERIAL

Material used in airframe construction

Airframe Materials Properties

Examples: