飛機隨著使用年限延長，疲勞問題所造成機構故障頻率亦會增加，而起落架為飛機最主要的構件，因此其疲勞壽命分析是相當重要的。 本研究目的是利用有限元素軟體建立輕型運動航空載具之起落架疲勞模擬平台，並分析起落架在不同材料、不同負載、不同外型下，其疲勞壽命之不同。材料主要是鋁合金6061-T6與碳纖維強化複合材料；外型有平板與圓柱外型起落架進行更換；負載則是考慮輕航機CH701設計之最大降落重量450Kg與FAA Part1規定之600Kg兩種。 在本研究中先以ASTM對於金屬與複合材料疲勞試驗規定之模型進行模擬，其結果與實驗值相符合，成功驗證利用有限元素軟體所建立之疲勞模擬平台的正確性。 由本研究結果可知起落架在不同靜態負載、材料與外型下，其y方向變形量與應力、應變之大小，以及其最大變形量與最大應力發生處。疲勞方面，則是可以得知鋁合金與複合材料起落架在450Kg負載下疲勞壽命皆可達108 cycle以上而不會產生破壞；鋁合金6061-T6在600Kg負載下圓柱起落架比平板起落架多15倍的循環壽命。碳纖維複合材料在600Kg負載下則是平板及圓柱則皆可達108 cycle以上。 With the extended life of the aircraft, caused by fatigue failure frequency will also increase the institution. Landing gear is the main components for aircraft, so the fatigue life analysis is very major. Purpose of this study is to use ANSYS Workbench to simulate the Special-Light Sport Aircraft landing gear fatigue. Analysis the landing gear’s fatigue life with different materials, different loads, and different shapes. Materials are aluminum alloy 6061-T6 and carbon fiber reinforced composite materials. Landing gear are leaf and cylindrical shapes to replace. Two loads are considered the design of CH701 maximum landing weight 450Kg and FAA Part1 600Kg. In this study, following the rules of ASTM for metals and composite materials fatigue simulate testing first. Consistent with the experimental results and successful of using finite element simulate fatigue. The landing gear with different static loads, different materials and different shapes from this study results, we can know its y direction of deformation , maximum stress , maximum strain ,and where it occur . About landing gear fatigue analysis results, aluminum alloy and composite materials landing gear fatigue life with 450Kg are above 108 cycle with no damage. The aluminum alloy 6061-T6 landing gear with cylindrical shape and 600Kg is 15 times fatigue life than the leaf shape landing gear . Carbon fiber-reinforced composites landing gear with leaf and cylindrical shape , and with 600Kg are above 108 cycle.
