GPS jamming and spoofing and relying on GPS, and GPS backup plan ?

Tango wrote:

I would think the fix for this is to make the GPS receiver directional and point it upwards?

Nice idea but it might still not work. A directional antenna doesn’t completely exclude signals from the unintended direction, it just has gain in one direction and attenuation in the other, broadly speaking. GPS signals are extremely weak, and a spoofer on the ground can use as much power as they like (power on the ground is easy compared to power in a satellite, and people on the ground are also much closer).

alioth wrote:

Nice idea [making the GPS antenna / receiver directional] but it might still not work. A directional antenna doesn’t completely exclude signals from the unintended direction, it just has gain in one direction and attenuation in the other, broadly speaking. GPS signals are extremely weak, and a spoofer on the ground can use as much power as they like (power on the ground is easy compared to power in a satellite, and people on the ground are also much closer).

I had a shower thought that the way our GPS antennas are installed is indeed directional. They sit on top of a relatively large Faraday cage / ground plane in the form of an airplane. The statement about signal strength remain valid, of course.

In the meantime, EASA issued a new version of SIB 2022-02R2: Global Navigation Satellite System Outage and Alterations Leading to Navigation / Surveillance Degradation.

Ultranomad wrote:

In the meantime, EASA issued a new version of SIB 2022-02R2 “Global Navigation Satellite System Outage and Alterations Leading to Navigation / Surveillance Degradation”.

@Ultranomad, are you OK to provide some short summary?

@arj1, sorry, forgot the link to the bulletin – fixed. It lists the affected FIRs, which are all either around Russia, or around the Middle East. It also provides 3 pages’ worth of recommendations to CAAs, ATM/ANS, air operators and aircraft manufacturers. The ones relevant for the crew are:

For jamming:
Ensure that flight crews and relevant flight operations personnel:

• are aware of possible GNSS jamming;
• verify the aircraft position by means of conventional navigation aids when flights are operated in proximity to the affected areas;
• check that the navigation aids critical to the operation for the intended route and approach are available;
• remain prepared to revert to a non-GNSS arrival procedure where appropriate and inform air traffic services in such a case; and
• report (AIREP) to air traffic services any observed irregularities.

For spoofing:
Ensure that flight crews and relevant flight operations personnel:

• are aware of possible GNSS spoofing;
• continuously monitor aircraft position using non-GNSS navaids and all available automatic navigation accuracy calculations, including the Estimated Position Uncertainty (EPU) figures;
• Monitor the GNSS time versus non-GNSS time sources;
• Closely monitor the ATC Frequencies in the vicinity of spoofing area;
• Apply the manufacturer’s instructions for the aircraft type on dealing with suspected spoofing, non-exhaustive list of examples of possible instructions could be such as:
  1. being ready to select HDG mode and manually adjust the flight course.
  2. being ready to ask for verification vector from ATC as long as needed.
  3. being ready to crosscheck with and switch to alternate PNT such as IRS and/or available ground facilities (Multi-DME and VOR/DME).
  4. being ready to exclude the GNSS signals within affected area.
  5. being ready to disable automatic INS/IRS updating.
• report (AIREP) to air traffic services any observed irregularities

Thanks!

Russia keeps jamming. According to Markus Jonsson (a pseudonym of a volunteer OSINT investigator in Sweden), 873 aircraft have suffered GPS outages on 15-16/03/2024. Here is a map of jamming events:

the map aligns with my observations from a recent flight to Norway, VOR is your (only) friend

Hi
Rookie pilot here, flying VFR in a SEP, with WAAS GNSS and Skydemon
(and, a paper map as well, of course )

I will be flying in the dark red areas tomorrow,
and wonder what I should expect?
Will my Skydemon track look like a seismograph during a Richter scale 8 earthquake?

Anyone with experience?

Cheers//jr

BlueOcean wrote:

and wonder what I should expect?

Definitely expect to use a backup plan, and have a backup for the backup ! (VOR, etc.)
I would also say expect to lose a lot of information you normally get via GPS (GS, time to destination, synthetic vision, etc.)

This is corroborated as I’m hearing by airline pilots who suffer hours long outages (and on modern airliners, a lot of systems rely on GPS, not just navigation).
It’s also especially true over the Black Sea.