Structural detailing of fuselage of aeroplane /aircraft.

This presentation is about the structural detailing of fuselage of aeroplane .The fuselage or body of the airplane, holds all the pieces together. The pilots sit in the cockpit at the front of the fuselage. Passengers and cargo are carried in the rear of the fuselage. Some aircraft carry fuel in the fuselage; others carry the fuel in the wings.

1. SUBMITTED BY - SHASHWAT SRIVASTAVA ,1827056 , M8
STRUCTURAL DETAILING
OF FUSELAEGE OF
AEROPLANE

2. CONTENTS
1
INTRODUCTION 2 TYPES OF FUSELAGE
CONFIGURATION
3
STRUCTURAL MEMBERS IN
FUSELAGE 4
DIFFERENT MATERIALS
USED IN FUSELAGE

3. INTRODUCTION
Airplanes are transportation devices which are designed to move people and cargo
from one place to another. Airplanes come in many different shapes and sizes
depending on the mission of the aircraft. The airplane shown on this slide is a
turbine-powered airliner which has been chosen as a representative aircraft.
The fuselage, or body of the airplane, is a long hollow tube which holds all the
pieces of an airplane together. The fuselage is hollow to reduce weight. As with
most other parts of the airplane, the shape of the fuselage is normally determined
by the mission of the aircraft. A supersonic fighter plane has a very slender,
streamlined fuselage to reduce the drag associated with high speed flight. An
airliner has a wider fuselage to carry the maximum number of passengers. On an
airliner, the pilots sit in a cockpit at the front of the fuselage. Passengers and
cargo are carried in the rear of the fuselage and the fuel is usually stored in the
wings. For a fighter plane, the cockpit is normally on top of the fuselage, weapons
are carried on the wings, and the engines and fuel are placed at the rear of the
fuselage.

4. TYPES OF FUSELAGE CONFIGURATION
A. TRUSS STRUCTURE
The main drawback of truss structure is its lack of a streamlined shape. In this construction method,
lengths of tubing, called longerons, are welded in place to form a wellbraced framework. Vertical and
horizontal struts are welded to the longerons and give the structure a square or rectangular shape
when viewed from the end. Additional struts are needed to resist stress that can come from any
direction. Stringers and bulkheads, or formers, are added to shape the fuselage and support the
covering.
As technology progressed, aircraft designers began to enclose the truss members to streamline the
airplane and improve performance. This was originally accomplished with cloth fabric, which
eventually gave way to lightweight metals such as aluminum.

5. In some cases, the outside skin can support all or a
major portion of the flight loads. Most modern aircraft
use a form of this stressed skin structure known as
monocoque or semimonocoque construction
The truss-type fuselage frame is
usually constructed of steel tubing welded together in
such a manner that all members of the truss can carry
both tension and compression loads. In some aircraft,
principally the light, single engine models, truss
fuselage frames may be constructed of aluminum alloy
and may be riveted or bolted into one piece, with
cross-bracing achieved by using solid rods or tubes.
The welded steel truss was used in smaller Navy
aircraft, and it is still being used in some helicopters.
truss structure and plane

6. B. MONOCOQNE TYPE
Monocoque construction uses stressed skin to support almost all loads much like an aluminum
beverage can. Although very strong, monocoque construction is not highly tolerant to
deformation of the surface. For example, an aluminum beverage can supports considerable
forces at the ends of the can, but if the side of the can is deformed slightly while supporting a
load, it collapses easily.
Because most twisting and bending stresses are carried by the external skin rather than by an
open framework, the need for internal bracing was eliminated or reduced, saving weight and
maximizing space. One of the notable and innovative methods for using monocoque construction
was employed by Jack Northrop. In 1918, he devised a new way to construct a monocoque
fuselage used for the Lockheed S-1 Racer. The technique utilized two molded plywood half-shells
that were glued together around wooden hoops or stringers.

7. . To construct the half shells, rather than gluing many strips
of plywood over a form, three large sets of spruce strips
were soaked with glue and laid in a semi-circular concrete
mold that looked like a bathtub. Then, under a tightly clamped
lid, a rubber balloon was inflated in the cavity to press the
plywood against the mold. Twenty-four hours later, the
smooth half-shell was ready to be joined to another to create
the fuselage. The two halves were each less than a quarter
inch thick. Although employed in the early aviation period,
monocoque construction would not reemerge for several
decades due to the complexities involved. Every day examples
of monocoque construction can be found in automobile
manufacturing where the unibody is considered standard in
manufacturing.
Monocoque plane and structure

8. C. SEMIMONOCOQNE
Semimonocoque construction, partial or one-half, uses a substructure to which the airplane’s
skin is attached. The substructure, which consists of bulkheads and/or formers of various
sizes and stringers, reinforces the stressed skin by taking some of the bending stress from
the fuselage. The main section of the fuselage also includes wing attachment points and a
firewall. On single-engine airplanes, the engine is usually attached to the front of the fuselage.
There is a fireproof partition between the rear of the engine and the flight deck or cabin to
protect the pilot and passengers from accidental engine fires. This partition is called a
firewall and is usually made of heat-resistant material such as stainless steel. However, a new
emerging process of construction is the integration of composites or aircraft made entirely
of composites.
Semi-monocoque design overcomes the strength-toweight problem of monocoque
construction. In addition to having formers, frame assemblies, and bulkheads, the Semi-
monocoque construction has the skin reinforced by longitudinal members

9. Longerons usually extend across several frame
members and help the skin support primary bending
loads. They are typically made of aluminum alloy
either of a single piece or a built-up construction.
Stringers are also used in the Semi-monocoque
fuselage.
These longitudinal members are typically more
numerous and lighter in weight than the longerons.
They come in a variety of shapes and are usually made
from single piece aluminum alloy extrusions or formed
aluminum. Stringers have some rigidity but are chiefly
Semimonocoque plane and structure

10. STRUCTURAL MEMBERS IN FUSELAGE
i.Airframe
The skin of aircraft can also be made from a variety of
materials, ranging from impregnated fabric to
plywood, aluminum, or composites. Under the skin
and attached to the structural fuselage are the many
components that support airframe function
ii. Stringers
Stringers are also used in the semi monocoque
fuselage. These longitudinal members are typically
more numerous and lighter in weight than the
longerons. They come in a variety of shapes and are
usually made from single piece aluminum alloy
extrusions or formed aluminum.

11. iii. Longerons
The skin is reinforced by longitudinal members called
longerons. Longerons usually extend across several
frame members and help the skin support primary
bending loads. They are typically made of aluminum
alloy either of a single piece or a built-up construction
iv. Bulkheads:
Bulkheads are provides at point of introduction of
concentrated forces such as those from the wings tail
surface and landing gear. The bulkheads structure is
quite substantial and serves to distribute the applied
load into the fuselage skin.

12. ü LOADS ACTING ON FUSELAGE COMPONENTS
Aircraft structural members are designed to carry a load or to resist stress. In designing an aircraft, every square
inch of wing and fuselage, every rib, spar, and even each metal fitting must be considered in relation to the physical
characteristics of the material of which it is made. Every part of the aircraft must be planned to carry the load to be
imposed upon it.
The determination of such loads is called stress analysis. Although planning the design is not the function of the
aircraft technician, it is, nevertheless, important that the technician understand and appreciate the stresses
involved in order to avoidchanges in the original design through improper repairs.
The term “stress” is often used interchangeably with the word “strain.” While related, they are not the same thing.
External loads or forces cause stress. Stress is a material’s internal resistance, or counterforce, that opposes
deformation.

13. The degree of deformation of a material is strain.When a material is subjected to a load or force, that
material is deformed, regardless of how strong the material is or how light the load is.
There are five major stresses to which all aircraft are
subjected:
 Tension
 Compression
 Torsion
 Shear
 Bending
Stress acting on an Aircraft during flight, any maneuver that causes accelerationor deceleration increases
the forces and stresses on the
wings and fuselage.

14. DIFFERENT MATERIALS USED IN FUSELAGE
During the early days of aviation, primitive fuselages were built with wood. In the late 1920s and early 1930s, airplane
manufacturers started producing more fuselages from aluminum and steel. These metals offered more stability and greater
protection from the elements. Many military and reconnaissance planes today are made from titanium or carbon composite
materials because of the unique advantages these materials offer.
Some airplane fuselages are constructed in what is called a monocoque design, a design that relies largely on the strength of
the plane's shell to carry different loads. These elements aid in the construction of a streamlined fuselage, adding to the
strength and rigidity of a monocoque design. A typical semimonocoque fuselage can sustain considerable damage and still hold
together. Military fighter planes and other small aircraft typically have two or more fuselage sections. Larger planes can have
up to six different sections.
Maintenance workers may access systems and equipment within the fuselage through several doors, panels, and other
openings. The locations of these access points can be found by referencing servicing diagrams and manuals released by the
manufacturer for each type of aircraft.

15. MATERIALS USED ARE -
1.Steel fuselage
Stronger and stiffer, but also heavier, steel aircraft were also
built in the 1930s. The heavier weight of steel prevented it
from becoming a popular fuselage material. However, the
metal is used to make certain parts of an aircraft. Its
strength and stiffness make it ideally suited for use in landing
gears. The heat resistance of steel also makes it desirable for
use in the skin of supersonic planes.
Built in 1932, the Beechcraft Staggerwing is a primary
example of an airplane with a steel fuselage. The Staggerwing
was expansive to produce and became popular as a fast,
business airplane.

16. 2.Titanium Fuselages
With the same strength as steel and much lighter, titanium and titanium
alloys are ideal materials for building aircraft. These metals also resist
corrosion better than both aluminum and steel. However, the production
of airplanes made from titanium is very costly, which largely prohibits
wide commercial use of most titanium airplanes.
The most prominent example of a titanium fuselage is the SR-71 Blackbird.
First flown in December 1964, the SR-71 was a staple of US air
reconnaissance during the Cold War. During its 24 years of service, the
Blackbird spent around 2,800 hours in the air.
On March 6, 1990, the SR-71 flew its last flight from Los Angeles to
Washington DC in 1 hour and 4 minutes, at an average speed of around
2,100 miles per hour.

17. 3. Carbon Composites Fuselages
Graphite epoxy, or carbon-fiber-reinforced polymer, has become a
popular choice for today’s state-of-the-art commercial aircraft. Made
from resilient carbon fibers embedded in an epoxy resin, carbon
composite materials can be stacked in a number of ways to meet the
various demands of maintaining integrity during high-speed flight.
These carbon-fiber materials are about as strong as aluminum, yet
half the weight.
Carbon composite materials haven’t gained widespread use in the
aviation industry just yet, but Boeing’s 787 Dreamliner was the first
major plane to use the materials in over half of its fuselage.

18. 4. Aluminium fuselage
Since the end of the war, aluminum has become an integral part
of aircraft manufacture. While the composition of the aluminum
alloys has improved, the advantages of aluminum remain the
same. Aluminum allows designers to build a plane that is as light
as possible, can carry heavy loads, uses the least amount of fuel
and is impervious to rust.
In modern aircraft manufacture, aluminum is used everywhere.
The Concorde, which flew passengers at over twice the speed of
sound for 27 years, was built with an aluminum skin.The Boeing
737, the best-selling jet commercial airliner which has made air
travel for the masses a reality, is 80% aluminum.
Today’s planes use aluminum in the fuselage, the wing panes, the
rudder, the exhaust pipes, the door and floors, the seats, the
engine turbines, and the cockpit instrumentation.

19. 5. magnesium fuselage
Modern magnesium alloys can offer up to 30% mass reduction when directly
replacing aluminum components, which makes them very attractive to
designers and engineers. However, until recently, there have been
restrictions on the use of magnesium in aircraft interiors that have
been enforced through the SAE and the FAA.
The FAA has been working for the last seven years to assess the
safety issues associated with the introduction of magnesium into
the cabin interior. This work began with simplistic flammability
testing of a wide range of alloys that identified different ignition
behaviors of magnesium alloy types. This lead the FAA to
undertake full scale fuselage staged burn tests of seat structures.
The typical structural seat components are shown in Figure 1. The
seats tested in the full-scale fuselage assessment contained five
key parts fabricated from magnesium: spreader bars, seat leg
assembly, cross tubes, baggage bars and the seat back frame.

20. SIGNING OFF - SHASHWAT SRIVASTAVA , 1827056 , M8