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Modern aircraft heavily rely on several wireless technologies for communications, control, and navigation. Researchers demonstrated vulnerabilities in many aviation systems. However, the resilience of the aircraft landing systems to adversarial wireless attacks have not yet been studied in the open literature, despite their criticality and the increasing availability of low-cost software-defined radio (SDR) platforms. In this paper, we investigate the vulnerability of aircraft instrument landing systems (ILS) to wireless attacks. We show the feasibility of spoofing ILS radio signals using commercially-available SDR, causing last-minute go around decisions, and even missing the landing zone in low-visibility scenarios. We demonstrate on aviation-grade ILS receivers that it is possible to fully and in fine-grain control the course deviation indicator as displayed by the ILS receiver, in real-time. We analyze the potential of both an overshadowing attack and a lower-power single-tone attack. In order to evaluate the complete attack, we develop a tightly-controlled closed-loop ILS spoofer that adjusts the adversary's transmitted signals as a function of the aircraft GPS location, maintaining power and deviation consistent with the adversary's target position, causing an undetected off-runway landing. We systematically evaluate the performance of the attack against an FAA certified flight-simulator (X-Plane)'s AI-based autoland feature and demonstrate systematic success rate with offset touchdowns of 18 meters to over 50 meters.
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Controls for a nonlinear system arising in vision‐based landing of airliners
Abstract We use a novel backstepping method to solve a stabilization problem for a nonlinear system with delayed sampled outputs that are not accurately measured. We provide an application to a system arising in vision‐based landing of airliners that includes coupling between the lateral and longitudinal dynamics, for which we provide performance guarantees in the presence of the delay, nonlinearity, and sampling. Our major contributions are (a) designs of lateral and longitudinal controls for our nonlinear model of an aircraft landing on an unequipped runway, (b) mathematical proofs that our controls ensure that the aircraft being modeled achieves desired alignment with the runway during its align phase, under sampling and delays that arise from image processing of visual information, and (c) comparative simulations exhibiting considerable improvement in control performance compared with previous methods that did not take the coupling of the dynamics or imprecise delayed sampled measurements into account.
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- Award ID(s):
- 1711299
- PAR ID:
- 10453235
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- International Journal of Robust and Nonlinear Control
- Volume:
- 31
- Issue:
- 4
- ISSN:
- 1049-8923
- Page Range / eLocation ID:
- p. 1227-1244
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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