Slide 1

LECTURE 2 COMPOSITION OF AIRCRAFT WEIGHT MASS (WEIGHT) & BALANCE 1 MBC 3204 - SIR ARIFF AMC

Slide 2

WEIGHT DEFINITION Weight is the force that results from the acceleration by gravity on the mass of an object. W = mg In modern scientific usage, weight and mass are fundamentally different quantities. Mass is an intrinsic property of matter, whereas weight is a force that results from the action of gravity on matter: it measures how strongly the force of gravity pulls on that matter. 2 MBC 3204 - SIR ARIFF AMC

Slide 3

Continue.. MBC 3204 - SIR ARIFF AMC 3 However, in most practical everyday situations the word "weight" is used when, strictly, "mass" is meant. For example, most people would say that an object "weighs one kilogram", even though the kilogram is a unit of mass. weight will give us more stability

Slide 4

MBC 3204 - SIR ARIFF AMC 4 Therefore in our discussion later, please KNOW that WEIGHT is a MASS of aircraft.

Slide 5

Continue.. MBC 3204 - SIR ARIFF AMC 5 The lift generated by the airfoils of the aircraft must be able to overcome the weight. Why? Less weight will give us better performance More weight will give us more stability Excessive weight will cause the aircraft crash.

Slide 6

TIME TO THINK!! MBC 3204 - SIR ARIFF AMC 6 Do you agree with all the facts given?? Give any examples to proves this fact. You may relate it with anything in your life. Not necessarily related with aviation. THINK OUT OF THE BOX!

Slide 7

WEIGHT CONTROL MBC 3204 - SIR ARIFF AMC 7 When an aircraft is designed, it is made as light as the required structural strength will allow, and the wings or rotors are designed to support the maximum allowable weight. Weight is a critical factor for an aircraft. Excessive weight reduces the efficiency of an aircraft and the safety margin available if an emergency condition should arise.

Slide 8

MBC 3204 - SIR ARIFF AMC 8 COMPOSITION OF AIRCRAFT WEIGHT

Slide 9

OVERVIEW MBC 3204 - SIR ARIFF AMC 9 All aircraft have a specified maximum mass. This limit must be respected, whether the aircraft is a micro-light or a Boeing 747 or an Airbus A380. Attempting to fly an overloaded/overweight aircraft can cause various effects (Performance and stability control)

Slide 10

MBC 3204 - SIR ARIFF AMC 10 To ensure aircraft can fly safely, limitation are set by the design engineer. Maximum Take-Off Weight (MTOW): The maximum permissible weight to conduct a takeoff. Maximum Landing Weight (MLW): The maximum permissible weight to conduct a landing. Maximum Zero Fuel Weight (MZFW): The maximum weight of an aircraft which its structural limits would allow.

Slide 11

MBC 3204 - SIR ARIFF AMC 11 Maximum Takeoff Weight (MTOW) MTOW of an aircraft is the maximum weight at which the pilot of the aircraft is allowed to attempt to take off. It is the heaviest weight which should be limited in order to ensure the aircraft can fly safely during take-off. At its MTOW an aircraft complies with all the structural and performance requirements. The MTOW of an aircraft is fixed.

Slide 12

Continue.. MBC 3204 - SIR ARIFF AMC 12 It does not vary with altitude or air temperature or the length of the runway to be used for takeoff or landing. MTOW is usually specified in units of kilograms or pounds. What is the difference between kilogram (kg) and pound (lb)??

Slide 13

Maximum Landing Weight (MLW) MBC 3204 - SIR ARIFF AMC 13 The maximum permissible weight to conduct a landing. What will happen if the aircraft weight during landing is greater than MLW? What is the possibility?

Slide 14

MBC 3204 - SIR ARIFF AMC 14 The Zero Fuel Weight (ZFW) of an airplane is the total weight of the airplane and all its contents, minus the total weight of the fuel on board. When an airplane is being loaded with crew, passengers, baggage and freight it is most important to ensure that the Zero Fuel Weight does not exceed the Maximum Zero Fuel Weight. Designers of airplanes can optimize the MTOW and prevent overloading in the fuselage by specifying a MZFW. This is usually done for large airplanes. Most small airplanes do not have a MZFW specified among their limitations. Maximum Zero-Fuel Weight (MZFW)

Slide 15

Example.. MBC 3204 - SIR ARIFF AMC 15 For example, if an airplane is flying at a weight of 5,000 lb and the weight of fuel on board is 500 lb, the Zero Fuel Weight is 4,500 lb. Some time later, after 100 lb of fuel has been consumed by the engines, the total weight of the airplane is 4,900 lb and the weight of fuel is 400 lb. What is the Zero Fuel Weight?

Slide 16

All Up Weight (AUW) The total weight of the aircraft including of all items at any specific time. During take off All up weight (AUW) must not exceed the Maximum Take Off Weight (MTOW) For Take-Off: AUW/TOW MTOW 16 MBC 3204 - SIR ARIFF AMC

Slide 17

Continue.. MBC 3204 - SIR ARIFF AMC 17 During landing All up weight (AUW) must not exceed the Maximum Landing Weight (MLW) For Landing: AUW/LW MLW Total ZFW also must not exceed the Maximum Zero Fuel Weight (MZFW). ZFW MZFW

Slide 18

IMPORTANT MBC 3204 - SIR ARIFF AMC 18 For Take-Off: AUW/TOW MTOW For Landing: AUW/LW MLW

Slide 19

All Up Weight (AUW) Where, PAYLOAD = Passengers & Cargo FUEL = Flight Fuel + Reserve Fuel DOW = Dry Operating Weight DOW also known as Aircraft Prepared for Service (APS) AUW = DOW + PAYLOAD + FUEL 19 MBC 3204 - SIR ARIFF AMC

Slide 20

Dry Operating Weight (DOW) @ APS Basic Weight + Crew & Baggage Basic Weight It consists of Empty Weight + Basic Equipment Weight. Empty Weight Weight of airframe, engines and standard structures. Basic Equipment Weight Weight of common installations inside the airplane. 20 MBC 3204 - SIR ARIFF AMC

Slide 21

Payload The weight of all persons and items of load carried in an aircraft for which a fare or charge is being paid. PAYLOAD = Passengers + Cargo 21 MBC 3204 - SIR ARIFF AMC

Slide 22

22 Fuel FUEL = Flight Fuel + Reserve Fuel Flight Fuel = It is the weight of the fuel required for and burnt during a flight. With the given flight distance and mean airspeed, Flight Fuel can be calculated as follows: Flight Fuel = Fuel Flow Flight Time Where, Flight time= Distance / Mean Airspeed

Slide 23

All Up Weight (AUW) However, AUW is not same during Take-off and landing. Why? During TAKE-OFF: AUW during Take-Off=DOW + PAYLOAD + (Flight Fuel + Reserve Fuel) During LANDING: AUW during Landing =DOW + PAYLOAD + Reserve Fuel Note that, as a flight progresses, flight fuel is consumed and finished. 23 MBC 3204 - SIR ARIFF AMC

Slide 24

24 RELATIONSHOP BETWEEN WEIGHT TERMINOLOGY

Slide 25

MBC 3204 - SIR ARIFF AMC 25 Basic Aircraft + Basic Equipment Crew, Crew Baggage + Equipment Cargo / Freight Passengers + Baggage Fuel Basic Weight Payload Variable Load DOW or APS Weight Disposable load Take-off Weight

Slide 26

MBC 3204 - SIR ARIFF AMC 26 Exercise on Definition of Weight State true of false. If false, correct it. 1.Disposable load = usable fuel + payload 2.Payload = Passenger Load + Cargo Load 3.Variable Load = Crew load + equipment load 4.APS Weight = Dry operating Weight (DOW) 5.APS Weight = AUW Disposable Load 6.APS Weight = ZFW Payload 7.Basic Weight + Variable Load + Disposable load = AUW 8.ZFW Payload = DOW 9.Basic Weight = Basic equipment weight + Airframe + engine + unusable fuel. 10.This course is easy!