Abstract
Airborne self-collisions occur primarily in military aircraft because of external stores and are frequently experienced by personnel operating these aircraft. In most cases, objects causing self-collisions are irregularly shaped and unstable. Consequently, the trajectories of these objects are uncertain. A framework for the probabilistic risk analysis of aircraft self-collisions is proposed in this study. Based on the probabilistic trajectory prediction model, methods for estimating the probability of collision (POC) and the corresponding risks were developed. Subsequently, a self-collision event involving an ejected gun shell was analyzed as a case study. A model considering random shell rotation, which continuously changes the drag characteristics and trajectories, was developed. Other uncertain factors associated with the aircraft and shell cases were considered. The most influential factors were selected based on the sensitivity analysis and were then used to calibrate the likelihood of the event using historical data. A Monte Carlo simulation, in conjunction with the probabilistic ballistic model, was performed to evaluate the POC. The POC was used to reflect the risk of engine failure up to the operational limit. The calculated risk indices were objective functions used for the design or operation optimization. Various risk measures were evaluated to reduce the incidence of failure and extend the aircraft’s flight envelope.
Highlights
Owing to various external stores, modern jet fighter aircrafts are exposed to the risk of self-collision
Some recent cases of aircraft self-collisions are shown in Figure 1, including the damages caused by gun shell case collisions (Figure 1a,b), as well as collisions of clips used for a general-purpose bomb (Figure 1c) and a fin separated from a missile (Figure 1d) with horizontal stabilizers
The severity factor of engine‐related loss loss of of aircraft aircraft (ERLOA) is the ratio of the number of aircrafts that fail to return to the base after non‐recoverable in-flight in‐flight shutdown shutdown (NRIFSD) events
Summary
Owing to various external stores, modern jet fighter aircrafts are exposed to the risk of self-collision. The calculated POC is used to provide the information for avoidance maneuvers when another object is predicted to approach the aircraft/spacecraft [3,4]. Several models for collision modeling and estimation have been proposed in the literature Both physics-based and data-driven models have been used to predict aircraft trajectories. Based on the trajectory predictions and their covariances for two objects, the POC can be calculated. The current POC analysis primarily focuses on learning the probabilistic trajectory models for aircrafts in an unstructured airspace [4], as well as investigating the potential risk associated with the operation of large constellations within the space debris environment [3]. Recommendations for mitigating the POC are discussed in the final section
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
