Advanced Field Balancing Techniques Ray D. Kelm, P.E. Kelm Engineering. For data input into a balancing program, the typical plane 1 and plane 2.Weight and Balance. Compliance with the weight and balance limits of any airplane is critical to flight safety. Operating an airplane above the maximum weight limitation compromises the structural integrity of the airplane and adversely affects its performance. Operation with the center of gravity (CG) outside the approved limits may result in control difficulty. Weight control. Weight is the force with which gravity attracts a body toward the center of the earth. It is a product of the mass of a body and the acceleration acting on the body. Weight is a major factor in airplane construction and operation, and demands respect from all pilots. Weight and Balance Forces Acting on an Airplane SUBJECT: Physics TOPIC: Torques and Moments DESCRIPTION: A set of mathematics problems dealing. Aircraft Control Surfaces Balancing downloads at Ebookmarket.org - Download free pdf files,ebooks and documents - Measuring Mass Properties of Aircraft. Aircraft weight and balance. A. general. You as pilot are responsible for the safe loading of your airplane and must ensure that it is not. Balance exercises can help you maintain your balance — and confidence — at any age. Mayo Clinic Healthy Living Program; Book: The Mayo Clinic Diet. Pilots praise performance of new single-aisle airplane. Learn more. Commercial Home. The Boeing Archives. ecoDemonstrator program checks out. Follow the steps on this page to learn how to balance a propeller for your RC airplane. Quick and easy! Large Model Airplane Program Page 3 of 29 11. Dynamically balancing control surfaces and sealing hinge line gaps are highly recommended to prevent flutter. The force of gravity continually attempts to pull the airplane down toward earth. The force of lift is the only force that counteracts weight and sustains the airplane in flight. However, the amount of lift produced by an airfoil is limited by the airfoil design, angle of attack, airspeed, and air density. Therefore, to assure that the lift generated is sufficient to counteract weight, loading the airplane beyond the manufacturer's recommended weight must be avoided. Air Balancing. Download32 is source for air balancing shareware, freeware download - Air Travel Toolkit - USA, Air Agression, Air Hockey Deluxe. Weight and balance - meaning and basic calculations. Compliance with the weight and balance limits of any airplane is critical to flight safety. If the weight is greater than the lift generated, the airplane may be incapable of flight. Effects of weight. Any item aboard the airplane that increases the total weight is undesirable as far as performance is concerned. Manufacturers attempt to make the airplane as light as possible without sacrificing strength or safety. The pilot of an airplane should always be aware of the consequences of overloading. An overloaded airplane may not be able to leave the ground, or if it does become airborne, it may exhibit unexpected and unusually poor flight characteristics. If an airplane is not properly loaded, the initial indication of poor performance usually takes place during takeoff. Excessive weight reduces the flight performance of an airplane in almost every respect. The most important performance deficiencies of the overloaded airplane are: Higher takeoff speed. Longer takeoff run. Reduced rate and angle of climb. Lower maximum altitude. Shorter range. Reduced cruising speed. Reduced maneuverability. Higher stalling speed. Higher approach and landing speed. Longer landing roll. Excessive weight on the nosewheel or tailwheel. The pilot must be knowledgeable in the effect of weight on the performance of the particular airplane being flown. Preflight planning should include a check of performance charts to determine if the airplane's weight may contribute to hazardous flight operations. Excessive weight in itself reduces the safety margins available to the pilot, and becomes even more hazardous when other performance- reducing factors are combined with overweight. The pilot must also consider the consequences of an overweight airplane if an emergency condition arises. If an engine fails on takeoff or airframe ice forms at low altitude, it is usually too late to reduce the airplane's weight to keep it in the air. Weight changes. The weight of the airplane can be changed by altering the fuel load. Gasoline has considerable weight - 6 pounds per gallon - 3. But it must be remembered that if weight is lowered by reducing fuel, the range of the airplane is decreased. During flight, fuel burn is normally the only weight change that takes place. As fuel is used, the airplane becomes lighter and performance is improved. Changes of fixed equipment have a major effect upon the weight of the airplane. An airplane can be overloaded by the installation of extra radios or instruments. Repairs or modifications may also affect the weight of the airplane. Balance, stability, and center of gravity. Balance refers to the location of the center of gravity (CG) of an airplane, and is important to airplane stability and safety in flight. The center of gravity is a point at which an airplane would balance if it were suspended at that point. The prime concern of airplane balancing is the fore and aft location of the CG along the longitudinal axis. The center of gravity is not necessarily a fixed point; its location depends on the distribution of weight in the airplane. As variable load items are shifted or expended, there is a resultant shift in CG location. The pilot should realize that if the CG of an airplane is displaced too far forward on the longitudinal axis, a nose- heavy condition will result. Conversely, if the CG is displaced too far aft on the longitudinal axis, a tail- heavy condition will result. It is possible that an unfavorable location of the CG could produce such an unstable condition that the pilot could not control the airplane. Figure 1: Lateral or longitudinal unbalance. Location of the CG with reference to the lateral axis is also important. For each item of weight existing to the left of the fuselage centerline, there is an equal weight existing at a corresponding location on the right. This may be upset, however, by unbalanced lateral loading. The position of the lateral CG is not computed, but the pilot must be aware that adverse effects will certainly arise as a result of a laterally unbalanced condition. Lateral unbalance will occur if the fuel load is mismanaged by supplying the engine(s) unevenly from tanks on one side of the airplane. The pilot can compensate for the resulting wing- heavy condition by adjusting the aileron trim tab or by holding a constant aileron control pressure. However, this places the airplane controls in an out- of- streamline condition, increases drag, and results in decreased operating efficiency. Since lateral balance is relatively easy to control and longitudinal balance is more critical, further reference to balance on this webpage will mean longitudinal location of the center of gravity. In any event, flying an airplane that is out of balance can produce increased pilot fatigue with obvious effects on the safety and efficiency of flight. The pilot's natural correction for longitudinal unbalance is a change of trim to remove the excessive control pressure. Excessive trim, however, has the effect of not only reducing aerodynamic efficiency but also reducing primary control travel distance in the direction the trim is applied. Effects of adverse balance. Adverse balance conditions affect airplane flight characteristics in much the same manner as those mentioned for an excess weight condition. In addition, there are two essential airplane characteristics that may be seriously affected by improper balance; these are stability and control. Loading in a nose- heavy condition causes problems in controlling and raising the nose, especially during takeoff and landing. Loading in a tail- heavy condition has a most serious effect upon longitudinal stability, and can reduce the airplane's capability to recover from stalls and spins. Another undesirable characteristic produced from tail- heavy loading is that it produces very light control forces. This makes it easy for the pilot to inadvertently overstress the airplane. Limits for the location of the airplane's center of gravity are established by the manufacturer. These are the fore and aft limits beyond which the CG should not be located for flight. These limits are published for each airplane in the Type Certificate Data Sheet, or Aircraft Specification and the Airplane Flight Manual or Pilot's Operating Handbook (AFM/POH). If, after loading, the CG is not within the allowable limits, it will be necessary to relocate some items within the airplane before flight is attempted. The forward center- of- gravity limit is often established at a location that is determined by the landing characteristics of the airplane. During landing, which is one of the most critical phases of flight, exceeding the forward CG limit may result in excessive loads on the nosewheel; a tendency to nose over on tailwheel type airplanes; decreased performance; higher stalling speeds; and higher control forces. In extreme cases, a CG location that is forward of the forward limit may result in nose heaviness to the extent that it may be difficult or impossible to flare for landing. Manufacturers purposely place the forward CG limit as far rearward as possible to aid pilots in avoiding damage to the airplane when landing. In addition to decreased static and dynamic longitudinal stability, other undesirable effects caused by a CG location aft of the allowable range may include extreme control difficulty, violent stall characteristics, and very light stick forces that make it easy to overstress the airplane inadvertently. A restricted forward center- of- gravity limit is also specified to assure that sufficient elevator deflection is available at minimum airspeed. When structural limitations or large stick forces do not limit the forward CG position, it is located at the position where full- up elevator is required to obtain a high angle of attack for landing. The aft center- of- gravity limit is the most rearward position at which the CG can be located for the most critical maneuver or operation. As the CG moves aft, a less stable condition occurs, which decreases the ability of the airplane to right itself after maneuvering or turbulence. For some airplanes the CG limits, both fore and aft, may be specified to vary as gross weight changes. They may also be changed for certain operations such as acrobatic flight, retraction of the landing gear, or the installation of special loads and devices that change the flight characteristics. The actual location of the CG can be altered by many variable factors and is usually controlled by the pilot. Placement of baggage and cargo items determines the CG location. The assignment of seats to passengers can also be used as a means of obtaining a favorable balance. If the airplane is tail- heavy, it is only logical to place heavy passengers in forward seats. Also, fuel burn can affect the CG based on the location of the fuel tanks. Management of weight and balance control. Weight and balance control should be a matter of concern to all pilots.
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