FLIGHT DISPATCH MANUAL AIRCRAFT WEIGHT AND BALANCE

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1 PAGE: 1 Table of Contents Table of Contents... 1 CHARTER General Basic load requirement Weight Balance Definitions Weight limitations Weight Calculation Balance... 12

2 PAGE: 2 CHARTER General The purpose of this chapter is to provide the information necessary to calculate and control the Weight and Balance of any loaded aircraft with reference to civil international commercial air transport aircraft, as this general category of aircraft has the most restrictive (stringent) requirements. Furthermore because of the many variations in the types of aircraft now engaged in public transport, plus the individual requirements of any particular Operator, this chapter is general in nature, and does not necessarily refer to any particular aircraft type, or apply to any particular Operator. When considering a specific aircraft and/or a specific Operator's requirements, reference must be made to the particular Weight and Balance Manual for that aircraft Basic load requirement It is a basic requirement for any civil commercial air transport aircraft to proceed safely from the aerodrome of Departure to its planned Destination and/or Alternate aerodrome. To ensure these safety requirements are met in term of fuel requirements, weight requirements and payload requirements, it is normal practice to accurately consider (at the planning stage of any flight), the calculation for each of the following, (or a combination of them): - Scheduled Aircraft Performance Requirements. - Fuel Flight Planning Requirements. - Payload (Weight and Balance) Requirements Weight Weight is a measure of the attractive force of the earth's gravity on any material body, and it is therefore an indication of the heaviness of that body. The total force of gravity (weight) acting on an aircraft in flight; tends to pull the aircraft down to the earth, and is only counter-balanced by the total lift produced by the airfoils. Weight reduces the flying capability of any aircraft. The heavier the aircraft is, it results in the: - Long takeoff distance. - Long landing distance. - Higher takeoff speeds. - Higher landing speeds. - Higher stalling speeds. - Lower rate and angle of climb. - Lower maximum operating altitude. - Lower aircraft's maneuverability. - Shorter range/distance Balance Balance is a prime importance to any aircraft's stability, maneuverability and safety in flight, and in this sense, refers to the location of aircraft s Center of Gravity (CG). The CG is the actual point where any aircraft is perfectly balanced, regardless of the actual configuration.

3 PAGE: 3 It is a legal certification requirement for every civil commercial transport aircraft to be tested, and proven, to show the safe range of acceptable balance that may be accepted both forward and aft of the CG. This range is published in the Aircraft Operations Manual or Weight and Balance Manual. 6.2 Definitions Aircraft configuration Planned utilization layout of aircraft interior space. Standard equipment Equipment independent of aircraft version and route to be flown, but must always be carried, includes e.g.: - Aircraft document briefcase - Compartment nets - Pantry and toilet water - Standard Airborne Maintenance Kit (AMK) - Baby cradle Version equipment Equipment belonging to a certain cabin version, such as - Passenger seats - Blankets and pillows - Partition walls in cabin. Route equipment Equipment required for a special route, includes e.g. Additional airborne Maintenance Kit. ARM (Moment ARM) The horizontal distance in inches from the reference datum line to the center of gravity of the item. The algebraic sign in plus () if measure aft of the datum, and minus ( - ) if measured forward of the datum. Baggage Equivalent to the term Luggage. Such articles, effects and other personal property of a passenger as are necessary or-appropriate for wear, use, comfort, or convenience in connection with the trip. 1. Checked baggage (also known as Registered) Equivalent to Registered Luggage, means baggage of which the carrier takes sole custody and for which carrier has issued a baggage check. 2. Cabin baggage Baggage of which the passenger retains custody (also known as Hand and/or Unchecked). Note: Crew baggage is baggage which is the property of operating crew and is separately identified. Balance condition A numerical expression of the position of the center of gravity. Balance limit The end points forward and aft of the range within which the center of gravity must lie for safe flight.

4 PAGE: 4 Ballast Deadload weight carried to achieve a particular balance condition. Basic index (Bl) A numeric expression of the center of gravity of the aircraft at its basic weight. Bulk Loading piece by piece. Cargo Any goods carried on an aircraft which are covered by airway bill. Center of gravity (CG) The point of the aircraft at which its total weight may be considered to act as a concentrated force. Center of gravity limits Specified forward and aft or lateral points beyond which the CG must not be located during takeoff, flight or landing. Center of gravity range The distance between the forward and aft CG limits indicated on pertinent aircraft specification. Datum (Reference Datum) An imaginary vertical plane or line from which all measurements of arm are taken. The datum is established by the manufacturer. Once the datum has been selected, all moment arms and the location of permissible CG range must be taken with reference to that point. Dead load Baggage, cargo, mail, ballast and equipment in compartments not included in Dry Operating Weight of the aircraft. Deck A structural floor level. For aircraft having one structural level only, this floor level will be referred to as the Main deck. For aircraft having more than one structural floor level, the different floor levels will be referred to as Lower Deck, Main deck and Upper deck, starting from bottom to top. Equipment in compartment (EIC) Equipment which is carried on the aircraft but which is not manifested and which is not, elsewhere, included in the weight composition. EiC includes e.g. - Additional Airborne Maintenance Kit (AMK) - Loading Accessories - Unmanifested catering equipment and food supply loaded in compartments - top of pallets installed in the loading system (Piggy Back). G Forces Increased/decrease of gravity forces exerted upon load during flight. Acceleration or deceleration can cause the weight of a load to increase or decrease and the change is expressed in "G". Thus, 2g would indicate that an item is, or must be, capable of withstanding, double the weight.

5 PAGE: 5 Galley The integral part of the aircraft where pantry/catering material is stored. Loading accessories Includes tiedown equipment, seat container (for the carriage of load on passenger seats in the cabin of the aircraft), containers for carriage of load which have been installed after removal of seats, ballast bags, stretchers, any containers used for isolation or protection of goods e.g. plastic bowls or plastic bags, garment racks, supporting planks and platforms, equipment for valuable cargo (pouches), collecting nets and bags, kennels for live animals, covers of any kind. Note: Unit Load Devices are not loading accessories. Mail Goods carried under the terms of an international postal convention. 1. Diplomatic Mail Governments' property carried under special agreements. 2. Service Mail Correspondence inter-airline or intra-airline which is carried on an aircraft under special permission from postal authorities. Mean aerodynamic chord (MAC) The average distance from the leading edge to the trailing edge of the wing. The MAC is specified for the aircraft by determining the average chord of an imaginary wing which has for the same aerodynamic characteristics as the following wing. Note: LEMAC is the leading edge of the mean aerodynamic chord. Moment The product of the weight of an item multiplied by its arm. Moments are expressed in pound-inches or inchpounds. Total moment is the weight of the aircraft multiplied by the distance between the datum and the CG. Moment index A moment divided by a constant such as 100, 1,000 or 10,000. The purpose of using a moment index is to simplify weight and balance computations of large aircraft where heavy items and long arms result in large, unmanageable numbers. Station A location in the aircraft which is identified by a number designating its distance in inches from the datum. The datum is, therefore, identified as station zero. The station and arm are usually identical, an item located at station plus 50 would have an arm of 50 inches. Traffic load {Payload) The total weight of all passengers, baggage, cargo, mail and extra equipment that may be carried on the aircraft, and also the difference in weight between Dry Operating Weight and Zero Fuel Weight. Tied own Equivalent to Restrain/Secure/Lash. The securing of the bulkload or part thereof to fixe restraint points within an aircraft or in a ULD, to conform to restraint and safety requirements. Tiedown equipment which have been authorized for use may comprise straps, webbing, nets, tiedown/lashing _rings, cable, chains and ropes.

6 PAGE: 6 Unit load device (ULD) A unit in which deadload is bulkloaded and subsequently loaded as a unit into the aircraft. (See also Aircraft Equipment) Version The designator used to indicate the aircraft configuration together with the details of the equipment carried. Weight 1. Basic Empty Weight The weight which includes all fixed equipment, system fluids, unusable fuel and configuration equipment including galley structure. 2. Catering Weight Equipment and supplies of in-flight distribution to passengers and crew. 3. Dry Operating Weight (DOW) The basic weight of aircraft plus operational items, e.g. crew, flight equipment, pantry and standard AMK and is equivalent to Operational Empty Weight or the aircraft prepared for service weight. 4. Landing Weight (LW) A legal requirement that aircraft will not normally take off at any weight in excess of that which will permit the aircraft to land at destination or alternate at weight less than Maximum Landing Weight. Landing Weight is either Zero Fuel Weight plus Reserve fuel or Takeoff weight minus Trip Fuel. 5. Pantry Weight Removable catering equipment. 6. Standard Weight The statistically arrived at weight approved by government authorities for weight and balance purpose for items of load regularly carried. 7. Takeoff Weight (TOW) Zero Fuel Weight plus Takeoff Fuel. 8. Tare Weight The weight of an empty unit load device. It includes all liners and/or fittings, etc., when these are required by the specification or as registered with IATA. 9. Zero Fuel Weight (ZFW) Equivalent to Dry Tank Weight. The combination of Dry Operating Weight plus Traffic Load or Takeoff Weight minus Takeoff fuel. 6.3 Weight limitations Weight limitations In order to get the aircraft, the right weight at its most safety, the values of weight, as stated below, must be adhered to:

7 PAGE: 7 Basic Airplane Weight Basic Airplane Weight known also as Airplane Empty Weight or Empty Operating Weight which consisting of the total weight of the airplane structure, power plants and all permanent fixtures and equipment plus the weight of any unusable fuel, undrainable oil, the hydraulic system, any other undrainable fluids (water injection, anti-ice) and any undrainable water systems. In the above configuration, the airplane must be weighed by the manufacturer before initial delivery to any operator. Under certification requirements it must be re-weighed at regular intervals and a revised BASIC AIRPLANE WEIGHT SCHEDULE must be published, normally in the operator's Operations or weight and balance manuals. Any modification or installation of additional permanent equipment in an airplane require the immediate re-issue of a revised Basic Airplane Weight schedule. Dry Operating Weight (DOW) Known also as Airplane Prepared for Service Weight (APSW) or Adjusted Operating Weight. In addition to know the airplane's basic weight, it is also necessary to calculate the total weight of the many variable items that are necessary to be carried on any public transport airplane for any particular flight. Such items are collectively known as OPERATING ITEMS, and may vary between individual operators and may also vary for each individual flight. OPERATING ITEMS include the total weight of technical and cabin crew with their baggage, food.and drink, oil, all full fluid systems, water and all other removable equipment (spare parts, emergency equipment, life rafts and ballast). It is normal airline practice to publish the total weight of the OPERATING ITEMS as one weight, in order to simplify weight calculations prior to any particular flight. DOW = Basic Airplane Weight Operating Items Maximum Zero Fuel Weight It is the value of weight that must not be exceeded by the weight of the aircraft with all loads except fuel. This is the weight beyond which any increase in load must consist entirely of fuel to avoid undue stress on the wing structure. The Maximum Certificated Landing Weight is therefore based upon the strength of the wing joint points (the points where the wings are connected to the aircraft body). It is normal practice for airplanes to have only one MCZFW, however because it is a structure design limitation, certain states of manufacture permit the use of a limited range of MCZFW, always provided the airplane operating within the published limiting design VMO/MMO speeds. ZFW = DOW Traffic load or Takeoff Weight- Takeoff fuel Maximum Takeoff Weight This is the maximum permitted weight at brake release at takeoff. It is the value of weight that must not be exceeded by the weight of the aircraft with all loads and the amount of fuel at the time of taking off. It is a legal requirement that no public transport airplane may takeoff at a weight in excess of the Regulated Takeoff Weight (RTOW) for the departure aerodrome. Furthermore, the RTOW may be a lower weight than Maximum Certificate Takeoff Weight (MCTOW) for the airplane. Thus, on occasions it may be necessary to reassess the original desired Takeoff fuel and or desire traffic load in order to ensure the airplane complies with the certification and operating regulations. In such cases, it is normal to first try to reduce the total takeoff fuel requirement (by adopting a different legal operating/cruise procedure) and then, generally only as a last resort, is any reduction of traffic load considered. TOW = ZFW Takeoff fuel

8 PAGE: 8 Maximum Landing Weight It is the value of weight that must not be exceeded by the weight of the aircraft with all loads and the amount of fuel at the time of landing. It is a legal requirement that a public transport airplane will not normally takeoff at any weight in excess of that, which will permit the airplane to land at either the planned destination or alternate aerodromes, at a weight which is the lesser of either, Maximum Certificated Landing Weight (MCLW) or Regulated Landing Weight (RLW). The landing gear is required to cushion the impact sufficiently at touchdown so as to prevent excessive loads being transmitted into the aircraft structure. The force of impact can be kept within the capabilities of the landing gear if the downward velocity is sufficiently reduced by the pilot and the weight of the aircraft is within the permissible weight. By its nature, an aircraft has its own weight as Basic Weight of Aircraft. The aircraft with only its basic weight is inoperative and not ready to service yet unless it is equipped with crews and pantry of food. The weight of crews and pantry are varied in accordance with the aircraft type and flight routing. With the combination value of aircraft s basic weight, crew and pantry weight, we can have the value of Dry Operating Weight which is the weight of the aircraft ready for service. LDW = TOW- Trip fuel or ZFW Reserve fuel Traffic Load or Payload This is the total weight-of all passengers, passenger baggage and cargo (freight) that may be carried on an airplane and is also the difference in weight between the DOW/APSW and the ZFW, therefore the weight that should be considered on each flight will be the kind of load on board which is called Traffic Loads such as: a.) Passengers The seat capacity of passengers will be varied in accordance with the cabin configuration of each aircraft type. b.) Baggage All passenger's baggage of which the actual weight can be obtained from the check- in counter, will be loaded onto the aircraft in accordance with the load plan. c.) Cargo According to its nature, the goods accepted on board as cargo may be loaded with Unit Load Devices (ULD) or in bulk of aircraft. d.) Mail Most of mail or postal matter in a small number can be loaded in bulk compartment or ULD in accordance with the load plan. e.) Unit Load Devices (ULD) ULD are aircraft equipment used to load baggage, cargo and mails. The weight of ULD is considered as Traffic Load and must be loaded onto the aircraft in accordance with compartment configuration. By combining the weight value of passengers, baggage, cargo, mail and ULD together, the Traffic Load or Payload can be obtained. If we add the weight of Traffic Load to the Dry Operating Weight, we will get the value of Zero Fuel Weight which must not exceed the Maximum Zero Fuel Weight. As Dry Operating Weight is fixed for each flight, the actual traffic load may be limited by any or either of - Maximum Zero Fuel Weight. - Maximum Takeoff Weight. - Maximum landing Weight.

9 PAGE: 9 - Maximum Tank capacity - Aircraft compartment loading limitation. The Zero Fuel Weight is the weight of the aircraft with all loads except fuel. When the aircraft is filled up with the Takeoff fuel, we will get the value of the Takeoff Weight which must not exceed the Maximum Takeoff Weight. To fly from one place to another, a certain amount of fuel call Trip Fuel will be used. To get the value of Landing Weight, we have to subtract the Actual Takeoff Weight with the Trip Fuel. From this calculation, the Actual Landing Weight obtained must not exceed the Maximum Landing Weight. All mentioned above is the Weight Control. For Balance Control, the concentrated area should be in the lower part of the aircraft which is compartment area. Since all loads in the cabin tend to be the same for every flight, therefore, we have to make pre-loading before so as to gain the Balance Control of the aircraft before the departure time.

10 PAGE: 10 Diagram of Operating Weights BASIC AEROPLANE WEIGHT = Structures, power units Fixtures etc. WEIGHT OF OPERATING ITEMS = Movable, changeable or consumable items = DRY OPERATING WEIGHT = Aeroplane prepared for service weight TRAFFIC LOAD = Payload = ZERO FUEL WEIGHT = Must not exceed MCZFW TAKEOFF FUEL = Total fuel less required for startup, APU etc. = TAKEOFF WEIGHT = Must not exceed RTOW START UP and TAXI FUEL TRIP FUEL = = RAMP WEIGHT Must not exceed MCRW LANDING WEIGHT Must not exceed RLW

11 PAGE: Weight Calculation OPERATING WEIGHT = Dry Operating Weight Takeoff Fuel TRAFFIC LOADS = Passengers with their Cabin Baggage Checked Baggage Cargo Post Office Mail and Company Mail Unit Load Device (ULD) Route Equipment and Extra Loading Equipment ZERO FUEL WEIGHT = Dry Operating Weight OR Traffic Loads Takeoff Weight - Takeoff Fuel Operating Weight OR Traffic Loads TAKEOFF WEIGHT = Zero Fuel Weight OR Takeoff Fuel Landing Weight Trip Fuel Zero Fuel Weight OR Remaining Fuel LANDING WEIGHT = Takeoff Weight - Trip Fuel

12 PAGE: Balance We can consider Load Sheet as a matter of calculation is an effort to trying to get the aircraft of the balance table, balance calculations, center of gravity and stabilizer setting are c sake of safety and Fuel economy. Completed balance table, balance calculations, center of gravity and stabilizer setting are clearly defined in the respective Aircraft Operating Manual or Weight and Balance Manual.

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