The most advanced form of spoofing so far. Aircraft have completely lost their position information.

During the second half of September 2023, more than 15 reports of GPS signal interference were received from aircraft overflying an area near the Iran-Iraq border. According to the pilots' statements, this was a previously unobserved type of spoofing, which in most cases caused not only a failure of the GPS navigation system, but also a complete loss of position information from inertial navigation and other instruments. The US FAA responded to these events by issuing an official warning to all civil aviation operators.

According to the OPS Group, at least 16 aircraft of various types have reported partial or complete loss of GPS service. These included smaller business aircraft such as Gulfstream 650 and Challenger 600, as well as higher capacity Embraer 190 and Boeing 737 aircraft. The loss of positional information did not exclude the largest transport giants, the Boeing 747 and 777. The event, which occurred on the border of the Baghdad FIR and Tehran FIR, is unprecedented in civil aviation.

Compared to the standard types of interferences observed, where the aircraft keeps the ability to navigate due to other systems, in this case failure of the inertial system IRS, the VOR/DME radio navigation unit and loss of time information also occurred.  This was probably because the instruments were not disconnected in time from the false satellite signal used by them. After the incident, the aircraft had to be manually navigated (i.e. vectored) by ATC according to radar information.

In its article, the Austrian company OHB Digital Solutions emphasises the importance of implementing the new GNSS Interference Detection & Analysis System (GIDAS). This would provide early detection of a non-authentic GNSS signal and application of preventive actions. The new type of interference may pose a significant threat not only to air transport and therefore needs to be thoroughly analysed and the necessary countermeasures put in place. GCE has a wide experience with different types of RFI interference and therefore this event is very interesting for us. You can read more about our cooperation with OHB Digital Solutions and our experience with the GIDAS detector, which has been part of several of our experiments and monitoring campaigns in various locations, in this article.

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