The Weight and Balance of the Aircraft - Case Study Example

Question Weight and balance check is always carried out after a specified time to ensure safe operation of the aircraft. It involves checking the weight and centre of gravity of the aircraft and make a comparison with the datasheet from the manufacturer. The recorded information after the check helps the aircraft operators (pilots) to ensure safety and efficient operation of the aircraft both at the take off point and on air. Introduction The weight and balance of the aircraft are most important factors that must be considered during the design and operation periods. They influence the flight characteristics and performance of the aircraft. Pilots are always provided with the datasheet containing the details concerning the weight and balance of the aircraft. They are advised to ensure that the weight of the aircraft ready to take off does not exceed the maximum take off weight authorized by the designer. This is done to ensure good efficiency in terms of performance to the aircraft during take off on air and during landing. An aircraft with the poor stability as a result of imbalance or overload consumes a lot of fuels for flight maintenance and may cause an accident. The data sheet for weight and balance is always be checked and compared with the real weight of the aircraft after a specified period of time in use has elapsed. This reduces chances if instability and overload which compromise the performance of the aircraft. The weight and balance checking involves determining the total weight and centre of gravity of the aircraft. The personnel in charge will have to determine the datum of the aircraft and use it to calculate the total moments of the aircraft. Weight checks up involve determination of both lateral centre of gravity and longitudinal centre of gravity. Background information The centre of gravity is the point in which the total weight of the aircraft is concentrated .The personnel doing the balance check will ensure that it lies within the range provided by the manufactures to avoid instability cases. Datum (reference line) help the personnel in determining the moments used in the calculation of centre of gravity. Datum is determined by the manufacture and can be located anywhere with the aircraft. The distance measured from the datum to any part of the aircraft is called the arm. The weight and balance design is done by engineers after proper consideration of all the factors and should also be respected by the aircraft mechanics and pilots for safe and efficient operation of the aircraft. Pilots are provided with datasheet that contains the manufactures’ specifications in order to ensure the efficient operation of the aircraft. During the balance and weight check up, the personnel in charge is expected to confirm the empty centre of gravity (EWCG), basic weight, zero fuel weight and tare weight of the aircraft and record them an a data sheet used by the pilots. Tare weight is the weight of the empty aircraft while zero fuel weight is the weight of the aircraft without fuel. In the determination of the moments of aircraft wings mean aerodynamic chord is determined for the tapered wings. The (MAC) is the average distance from the trailing end to the leading end. For un-tapered wings the chord length is used as it is always known. In the case of tapered wings, the simple average chords are used. The most commonly used value is known as mean aerodynamic chord and it is a weighted average chord. The efficient and safe operation of the aircraft is the core business of any designer in the field of engineering and will always that aircraft realised for operation is properly checked and meet the required standards. Pilots are required to conduct balance and weight checks before every aircraft take off. The result from the check is compared with data in the AFM to confirm if the aircraft meet the requirement for safe flight. The basic equipments must all be installed properly during the air craft check up. The removal or addition of equipment will automatically alter the position of the centre of gravity. Therefore it is necessary to indicate the new value of the centre of gravity position in the datasheet used by the pilots in case there is addition or removal of any equipment from the aircraft. Proper entries made will, therefore, help the pilot in determination of the true values the weight and balance because without such information, pilots have no foundation to back up their decisions and calculations. Weight and balance check need not to be done on additional parts of negligible weight such as bolts, nuts and rivets. This is because they are of negligible weight and would not alter the CG of the aircraft. Pilots need to acquaint themselves with the relevant terms used to describe problems related to weight and balance. These terms are defined by GAMA such as the basic empty weight which is the standard empty weight added to the weight of the special and optional equipment installed in the aircraft. Payload (GAMA) is important information that help pilots in reviewing the weight and balance check information. This is the weight of the cargo, passengers and baggage that is loaded in the aircraft. It contributes the increase in total weight of the aircraft and may also change the position of the centre of gravity if not well arranged. The pilot is expected to ensure that maximum takeoff weight is not exceeded and loads arranged well. Conclusion. Failure to comply with the weight and balance limits of any aircraft is critical for flight safety. It is of extreme importance to conduct weight and balance check to avoid cases of overloading and instability of the aircraft. Balance and weight check helps in detecting changes in position of the centre of gravity and weight of the aircraft .By availing the new data sheet from the weight and balance check, it will help the pilots ensure safe loading of the aircraft This in turn results in safe and efficient operation of the aircraft. It is realized that apart from safety, operation of the aircraft above the maximum limitation compromises the structural integrity of the aircraft and adversely affect its performance. These cases may lead to more fuel consumption. Aircraft owners and operators ensure they provide up to date information about the aircraft weight, CG and any other necessary information that ought to be in the weight and balance records. Question 2 Change in centre of gravity causes instability of the aircraft. As long as it is within the allowable limits, the aircraft will still have adequate longitudinal stability and control. If the centre of gravity falls out of the range, the aircraft will be unstable and will have difficulties in recovering from a stall. If it enters a spin in the unstable state, the spin could become flat and may result in difficulty in recovery. The elevator might not produce enough force to rotate at slow take off speed. During a landing, there may not be enough elevator force to flare the aircraft and this leads to extended landing. . Change in centre of gravity causes change in cruise speed. An aircraft with the forward moved centre of gravity cruise faster due to reduced drag that comes out as result of smaller angle of attack Question3 An aircraft may have problems when towing in snow and ice conditions. It condition can cause disturbance to the aerodynamic and centre of gravity of the aircraft. When ice enters the internal moving parts and electrical systems moving parts, it can interfere with the normal operation of the aircraft. Pilot should inspect the wings and empennage surfaces to verify that the snow and ice are cleared. Ground heaters and anti- ice solution are used to free the frozen wheels. Before towing in these kinds of conditions, proper guidelines are required for improved safety .The following is the towing procedure. Before towing starts, ground locks should be installed and steering should be disconnected if necessary .De-icing should be carried out. Aircraft must be towed by the main gear as the immense breakaway load resulting from the ice may damage the nose gear The ATC is required before moving the area. The TBLT operator is expected to have enough skills that will enable him handle the delineation of movement of the aircraft. The contact between the ATC and the crew on the ground in charge of Towing is maintained by the ATC frequencies. The rule for the towing process should be maintained until aircraft is cleared off. This is done by the TBLT in coordination with the ATC. At the start, the aircraft is to be moved at low speed and avoid sharp turning radii. This is responsibility of the TBLT. The TBLT is advised not to use breaks during towing process unless in emergency cases. This is important for the safety of the aircraft. Based on the model and tow, the maximum speed is determined by the TBLT. The speed is expected to be as low as possible. The speed reduction is dependent on the aircraft weight and run way. Upon completion the aircraft should be position such that the nose gear is aligned by the aircraft References Administration, F., 2011. Rotorcraft Flying Handbook. 1st ed. New York: Skyhorse Publishing, I Aircraft Weight and Balance. 2014. [online] MzeroA.com. Available at: [Accessed 21 Apr. 2014].nc. weight and balance of the aircraft. 2014. [online] Pilotfriend.com. Available at: [Accessed 21 Apr. 2014]. WEIGHT AND BALANCE An Important Safety Consideration for Pilots. 2014. [online] Avstop.com. Available at: [Accessed 21 Apr. 2014]. Read More