Conceptualizing Naval Helicopter Landing Gear Engineering Essay

abstractizing Naval Helicopter get pitch engine room EssayThe land incline is an important part of an aircraft as uttermost as the take-offs and landing places argon concerned. The landing slope mechanisms (or structures) are pretty primary in case of the commercial chopper as compared to the commercial airplanes. But, that is non the case for the naval helicopters. Because of the not-so-friendly landing jibes, the naval helicopter must crap sophisticated landing gear mechanism connected with its fuselage. The build of the landing gear mechanism for the naval helicopter should be such that the helicopter can land safely in aircraft carrier as well move as in filth also, the mechanism should not fail chthonic the sea wave excitation, while in ground go over.b. Research on landing gearDuring the initial days of the human flying history, the flyers apply to dedicate the Skids as landing gears. The skids are still very more than in use for commercial helicopters. But , for the airplanes and for the naval helicopters swans are use loosely for the landing gears. The wheels are connected with the shock absorbers to form the landing gears. The landing gear, then, get connected with the fuselage in various fashions based upon the size of the aircraft. entirely the wheel based landing gears can broadly be categorized in three main categoriesConventionalTri-cycletandem bicycleFig.1 present three basic types of wheel based landing gearsTwo precedent wheels and a nookie tail wheel are used to form the courtly landing gear. The older aircrafts still have this type of landing gear. install handling is bit difficult here.The tri-cycle configurations has deuce (or multiple of devil) wheels at rear and minimum of one nose wheel (s) at front. It gives better ground handling comfort and used widely for small sized aircrafts. On the basis of the wheel arrangements, disparate types of tri-cycle arrangements are possible (as shown beneath)Fig.2 exhibit different types of Tri-Cycle configurations (as per Federal Aviation Administration nomenclature)The multiples of landing gears are placed in line to form a complex tandem landing gear system. Different combinations of tandem are possible (as shown at a lower place)Fig.3 covering different types of Tandem configurations (as per Federal Aviation Administration nomenclature)c. Conceptualizing Naval helicopter Landing caravanAfter studying different types of available landing gears configurations, I have decided to develop the landing gear construct of Single wheel main gear with dual wheel nose gear configuration. It s a kind of tri-cycle configuration.Fig.4 wake the rough landing gear conceptI have decided to use only deviousness take a hop as shock absorbing elements for the concept.d. Preliminary Design CalculationsIn rate further developing the concept, I have used the following infoTotal mass of the helicopter = 5126 KgSprung mass on apiece spring, m = 2563 KgDistance a mong the front and rear gear = 5 mDistance between the two rear gears= 2m standard landingVertical business line travel of the helicopter = 0.5 m/ instantVertical be speed = 0So, the relative speed between the embroider and the helicopter, v =0. 5 m/ southward=500 mm/secSo, the kinetic energy of the helicopter, KE = 0.5*m*v2 = 320375000 kg-mm2/sec2The energy stored in the torsion spring, SE= 0.5*k*r2 =0.5*kWhere, k= spring rate in N-mm/ full pointr=deformation of the spring =1 degree (assumed)Now, asKE = SE .eqn.1So, k= 640750000 N-mm/DegreeI bequeath use this spring rate for rest of the two landing limits to find out the deformations of the torsion springs.Hard landingVertical descent speed of the helicopter = 3 m/secVertical deck speed = -3 m/secSo, the relative speed between the deck and the helicopter, v =6 m/sec=6000 mm/secK= 640750000 N-mm/degreeSo, by use the eqn.1r= 12 degreeCrush landingVertical descent speed of the helicopter = 15 m/secVertical deck speed = 0m/secS o, the relative speed between the deck and the helicopter, v =15 m/sec=15000 mm/secK= 640750000 N-mm/degreeSo, by using the eqn.1r= 30 degreeSo, I will start my ADAMS program with the values obtained from this hand calculation and gradually delicately tune the values in order to meet the landing criteria.e. Converting the Conceptual Design to ADAMS MechanismsI have used the MSC ADAMS software for preparing two landing gear mechanism foundation options out of the conceptual design and the hand calculations. The two design options differ in terms of heights. parametric design advantage of the ADAMS software is utilized for creating the two design options. eon creating the two mechanism design options, the following ADAMS options are utilized principal Points are used for creating basic locations of all the important elements of the design (like tenderness of the wheels etc.)Torus Wheels of the landing gears are created using the torus option.Link every the structural members ( like top frame, axels etc) are created using this option.Box This animal is used for creating the landing deck of the air craft carrier.Torsion Spring This is for creating the front and rear torsion springs.Hinge Joint This option is for creating all the revolute joints of the mechanism.translational Joint This option is used for creating the translational joints.Contact The contacts between the wheels and the deck are created using this option.e.1. ADAMS Mechanism Option-1The mechanism option-1 looks like belowFig.5 exhibit the ADAMS Mechanism option-1 ArrangementThe points table for the mechanism option-1 looks like belowFig.6 Showing the point table for the mechanism option-1e.2. ADAMS Mechanism Option-2The mechanism option-2 looks like belowFig.7 Showing the ADAMS Mechanism option-2 ArrangementThe points table for the mechanism option-2 looks like belowFig.8 Showing the point table for the mechanism option-2e.3. Selecting the Optimum ADAMS Landing Gear MechanismThe selecti on of the best design out of the two options is do by observing the speedup values. The acceleration whiles for the hard landing aims (descent swiftness of the helicopter = 3 m/sec and upward deck speed = 3m/sec) for both the concepts are shown belowFig.9 Showing the hard landing condition acceleration temporary hookups for both the conceptsThe above mend is showing that the maximum acceleration value for the design -2 is more than50 m/sec2.The acceleration dapples for the coquette landing condition (descent velocity of the helicopter =15 m/sec and upward deck speed = 0 m/sec) for both the options are shown belowFig.10 Showing the crush landing condition acceleration plots for both the conceptsThe above plot is showing that the maximum acceleration value for the design option-2 is much higher in case of the crush landing condition.So, on the basis of the above two tests, it can be concluded that the design option-1 is better among the two options. Hence, I have selected th e design option-1 for further analysis.f. scrutiny the Selected ADAMS mechanism (design option-1) Against the Specified Landing Conditions general Landing Condition The acceleration plot for normal landing condition (descent velocity of the helicopter = 0.5 m/sec and upward deck speed = 0m/sec) for the design option-1 is shown belowFig.11 Showing the normal landing condition acceleration plots for the Design Option-1The above plot is showing that the maximum acceleration value for normal landing condition for the design option-1 is 7.5 m/sec2.Hard Landing Condition The acceleration plot for normal landing condition (descent velocity of the helicopter = 3 m/sec and upward deck speed = 3m/sec) for the design option-1 is shown belowFig.12 Showing the hard landing condition acceleration plots for the Design Option-1The above plot is showing that the maximum acceleration value for hard landing condition for the design option-1 is 48.1 m/sec2.Crush Landing Condition The acceleration plot for normal landing condition (descent velocity of the helicopter = 15 m/sec and upward deck speed = 0m/sec) for the design option-1 is shown belowFig.13 Showing the crush landing condition acceleration plots for the Design Option-1The above plot is showing that the maximum acceleration value for hard landing condition for the design option-1 is 119.6 m/sec2.g. Running the Vibration Analysis for the Selected ADAMS MechanismThe vibe analysis is performed for the Design option-1 using the ADAMS vibration plug-in. For simulating the sea wave oscillations, two acceleration actuators are used at front and the rear axles. iodine output pack is created at the COG of the top frame. The output channel is used for measuring the acceleration at the COG of the frame.Fig.14 Showing the frequence Response Analysis plot for the Design Option-1The pick of the above oftenness response plot indicates the resounding frequence for the design option-1. So, the resonating frequency here is 64.5 Hz .h. Consolidated Results for Design Option-1Parameters ValuesMaximum Normal Landing Acceleration (m/sec2) 7.5Maximum Normal Landing Acceleration (m/sec2) 48.1Maximum Normal Landing Acceleration (m/sec2) 119.6Resonating Frequency (Hz) 64.5i. DiscussionTask-1 This task is cover in the section-c and section-d.Task-2 This task is covered in Section-f.Task-3 This task is covered in section-g.Task-4 This task is covered in section-e.j. ConclusionThe ADAMS is a powerful tool for creating and testing a mechanism under specified conditions. The parametric ingest of ADAMS helps creating different design iterations easier.The design option-1 passed all the landing conditions specified for the assignment. Also, the resonating frequency observed for the design option-1 is 64.5 Hz.k. Referenceshttp//www.faa.gov/airports/resources/publications/orders/media/Construction_5300_7.pdfhttp//www.allstar.fiu.edu/aero/flight14.htmhttp//www.helis.com/howflies/skids.phphttp//www.aoe.vt.edu/mason/Mason_f/M96 SC.html