AIRPLANE STRUCTURES – STRUCTURAL UNITS

[Music] in order to understand the construction of the airplane it is necessary to consider its principal structural elements the material from which it is fabricated and the load to which it will be subjected with regards to the structure of an airplane it may be divided into four main structural units each with distinct functions the fuselage is the central unit to which the other units are attached the wings provide most of the lift for the structure the control surfaces are used to guide the airplane in flight these consists of the m fijn our tail assembly and the ailerons our wing control surfaces which are attached to the trailing edge of each wing the alighting gear from its movement of the airplane on the ground in the single-engine airplane the fuselage or body of the airplane carries the engine cowling the pilots cockpit or canopy and the tail group the sixth surfaces in this group horizontal stabilizer and vertical fin stabilize the flight of the airplane the movable surfaces rudder and elevator control it the ailerons are hinged to the trailing edge of the wing and are used to raise one wing while depressing the other for banking the airplane wing flaps are also hinge to the trailing edge of the wing and are used to decrease the landing speed of the airplane the main units comprising the alighting here are the oleo struts or shock absorber and the retracting mechanism in airplane construction some materials are employed more generally than others steel alloy is used where maximum strength is required to withstand strain and vibrations such as those exerted by engines sheet aluminum alloy is used in the skin covering and is the material used in the manufacture of Life Park aluminum alloy extrusions of various shapes are used in the formation of far ribs braces and in the fabrication of the sub-assembly streamlined cubing internally break to use where exterior bracing is required the extruded shapes are cut to size and vent to shape before the parts are fabricated movable tail surfaces and ailerons are usually fabric covered fiber is used for pulleys gaskets and washers fabric reinforced rubber hose is used in a hydraulic system and sponge rubber for vibration dampers and insulation copper is used in a multitude of electrical contacts and connections bronzes use in bushings bearings and hydraulic fitting the canopy over the pilots cockpit is constructed of a synthetic material most of the material used in airplane construction are provided with a protective coating sheet aluminum alloy is thoroughly cleaned in a hot cleansing solution and then spray painted with an oxide primer cubing is carefully clean and the nco to prevent foreign substances from lodging in the tubing during assembly steel fittings were possible our cadmium slated to prevent rust and corrosion aluminum alloy parts are given an anodic treatment which deposits a compound of the metal on the surface by electrolysis impregnated with nitrate dope and painted fabric-covered surfaces are stored until assembly the entire structure of the airplane must be able to whip them safely the loads that will be placed on it in service these loads may be exerted on the structure in combat maneuvers the wings must be able to send both positive and negative loads the positive lobe being one which acts upwards in relation to the airplane maximum positive load may be reached in pulling out of a diet maximum negative lows may be imposed in an abrupt push over or sudden thrust forward on the six inverted flight also applies a high- load turbulent air may also impose high wing load negative in the downdraft and positives in the abstract drag due to the speed of the airplane is exerted on all exterior surfaces when landing grounds loads must be able to also buy the structure of the airplane a few elementary factors affecting airplane structures have been presented here other films will deal with the construction of the component parts of the airplane [Music]