Abstract

Manned aircraft structural design is based on structural safety factor of 1.5, and this safety factor is equivalent to a probability of failure of between 10-2 and 10-3. The target failure probability of FARs is between 10-6 and 10-9 per flight according to aircraft type. NATO released STANAG 4703 to established the airworthiness requirements for small UAV which is less than 150kg. STANAG 4703 requires the Target Level of Safety according to MTOW. The requirements of failure probability for small UAV is between 10-4 and 10-5. In this paper, requirements of airworthiness certification for small UAV were investigated and the relationship of safety factors to the probability of structural failure is analyzed to reduce measure of safety factor and structural weight of unmanned aircraft.

Keywords

• Factor of safety;
• Unmanned Aerial Vehicle(UAV);
• Probability of structural failure;
• Target Level of Safety

• 안전 계수;
• 무인기;
• 구조물의 파손확률;
• 목표안전수준;

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Acknowledgement

Grant : 경량구조 및 구조안전성 향상기술 연구

Supported by : 기초기술연구회

References

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