1. Home
  3. Squawk Ident

Squawk Ident


Given recent instances of GPS spoofing/hacking, what steps has your flight department taken to prevent or minimized these occurrences?

Before flying in that part of the world, I performed some tests on navigation accuracy with all GPS receivers deactivated. Using a portable GPS with input to our iPad and Scott IPC (and Foreflight) activated with our flight plan, we determined that the aircraft position varied by no more than 300–500 ft from course relying on IRS and VPU (DME/DME) inputs. This remained consistent even while flying over remote desert regions of North Africa, well away from the threat area, where DME signals are more widely scattered than in Europe and CONUS. While transiting the Indian Ocean, far from any ground navigation, IRS provided considerably better than 1-mile accuracy, usually drifting around 1500–2000 ft from course, and after 90 min of flying. During subsequent flights around the southern border of the threat area, we placed the GPS receiver low in a window on the opposite side of the plane from the danger zone to attenuate any disruptive signals, and then we disabled the onboard GPS. Evidently, we were not targeted, since we received no indication of interference from the aircraft GPS such as reliability warnings or reporting a position different than what we knew it to be). The portable receiver was reporting H & V Quality Factors in the 10- to 40-ft range, and DME/DME signals from friendly nations maintained excellent navigation accuracy. We feel this technique offered the best insulation from problems. If we had encountered a problem, at best we would stay on course, and at worst we would see anomalies and know to widen our range to the boundary.

Dennis O’Brien
ATP. Falcon 7X
Client Av Mgr
Solairus Aviation
Golden CO


Changing SOPs is our preference. After reviewing the appropriate procedures, we disconnect the GPS before arriving in the area of concern, and continue with other navigation means such as VOR, DME/DME, or VOR/DME. Finally, we’ve added a portable GLONASS (Global Navigation Satellite System)/Galileo receiver to be coupled with a flightdeck app.

Yariv Tawil
ATP. Global Express
Lead Captain
Besançon, France


We check the area of operations to see if it presents a hazard with GPS jamming or spoofing. We then provide the crew with an aircraft-specific checklist on how to handle a GPS spoofing/jamming event. Honeywell and Gulfstream have provided crews with great info about what to expect and how to handle these events. We’ve also created cockpit checklists referencing that data.

Brent Keyes
ATP. Gulfstream G550
Dir of Aviation
Moorland Promontory
Royal Palm Beach FL


OEMs were initially reluctant to offer solutions or mitigation procedures. Personally, when flying in affected regions, I monitor GNSS sensors. When I start seeing abnormal GNSS degradation, I immediately disable all GNSS sensors. If airplane lateral oscillation presents itself due to low DME coverage, I also deselect DME/DME sensors. This reverts the navigation to IRS only. I understand the single-IRS limitation of 6.2 hrs in RNP-10 environment. On the Bombardier Global 7500, we have 3 IRSs working in unison. My reasoning is that there is little chance for the FMS to navigate off track for more than 4 miles during a relatively short time – less than 2 hrs – using our triple IRS installation. On re-entering unaffected airspace, I re-enable all sensors.

Réal Bougie
ATP. Global 7500
Contract Captain
Real Aviation
Longueuil QC, Canada


When flying into an affected area, we deselect the GPS Hybrid function of our IRUs. Then, when the GPS starts to fail, we deselect the GPS from the solution. That protects the blending of the FMSs. Unfortunately, we still have to operate in those regions. We try to route around the affected spots when possible.

Charles Matthews
ATP. Gulfstream G550
Solairus Aviation
Stafford Springs CT


First of all, we identify if the flight plan routing will take us through or near the areas of concern. Then we take a proactive approach and disable all the external navigation equipment that can “infect” our FMS, and allow only the independent in-plane system to navigate the airplane. We maintain IRS until the aircraft is out of the areas of concern and the GPSs can be re-enabled.

Morris Silverman
ATP. Gulfstream G650ER
Intl Captain
Hayward CA


It’s a GPS issue. We keep the sensors page open, then deselect the GPS, and finally fly on IRS, which now becomes the primary source. The sensors page remains open.

Alok Kumar
ATP. Falcon 2000LX
Mumbai, India


When GPS jamming is suspected, go back to using ground-based radio stations to verify position. In addition, match ground features to map if possible.

Tong Bee Ngak
ATP. Citation Sovereign, Learjet 60XR/45/35 & Gulfstream G150
Line Captain
Seletar Jet Charter


We’ve reinforced our SOP of tuning in available VOR navaids and keeping RMI needles on the PFD for additional SA throughout the flight. We’ve seen GPS integrity issues from DOD testing in CONUS in the past, which is what drove us to this as our SOP.

Matthew Harrah
ATP. King Air F90 & Kodiak 100
Senior VP of Technologies and Products
Mid-Continent Instruments and Avionics
Wichita KS


Our flight department has reviewed topics such as identifying where and when spoofing is happening. We’ve also discussed how to deactivate GPS signals from the FMS and navigation via IRS and VORs, or some other ground-based navaid.

John Scribner
ATP/CFI. Gulfstream G280
Daytona Beach FL


I always keep the spare ADF (automatic direction finding) radio tuned to the recognized frequencies for the final approach fix. Need to back up modern technology with the “grass roots.”

John Doersom
ATP/CFI. King Air 100/90 & Cessna 310
Former Captain
Doersom Aviation Services
Fairfield PA


We thoroughly brief all crews about the threat, the area, and the means of mitigation. This problem is spreading since the first reports a year ago over Iraq. Jamming is annoying, but spoofing is a serious hazard.

Chas Hunt
ATP. Global Express
Contract Captain
FGS Aviation
Corfe Castle, England


Unfortunately, it is impossible to reduce these attacks. However, our procedures have been revised and adapted to ensure correct positioning and avoid dependence on GPS only.

Alex Serck
ATP/Helo. Falcon 8X
Flyit Management
Sint-Martens-Latem, Belgium


Crew members have been briefed about this. If there is an option for the ILS, we will request it. The only interference we have had is noise over the radio while on the approach at PWK (Exec, Chicago IL).

Mike Halko
ATP/CFII. Citation Ultra
Northwest Flyers
West Chicago IL


Extended information is provided for the flight crews through notices, as well as a restriction on the dispatch of aircraft flying into affected areas without any navigation-related MEL items.

Konstantinos Filippidis
ATP. Airbus A320, Embraer EMB-145 & Premier I
Athens, Greece


There really isn’t anything we can do to avoid jamming due to our operations. However, we know what to look for, and we have procedures to follow when jamming occurs in order to mitigate elevation to spoofing.

Greg Woods
ATP. Gulfstream G650ER
Senior Director
Carlsbad CA


Last week, at PSP (Palm Springs CA), just prior to engine start, we experienced a yellow “CHK POS” on the Collins Pro Line 4. We checked that all inserted positions were correct, and RAIM 0.1, 11 satellites, both GPS receivers. We powered down/up and the messages did not reappear. All of this caused a 45-min delay. At that point, we were unable to determine the cause of the CHK POS message – whether it was military interference, spoofing/hacking, or a bad satellite. It’s still a mystery.

Don Keating
ATP. Challenger 604 & Bell 429
604 Management
Seattle WA


Keep up with the news concerning the problem areas, and stay in touch with pilots who operate in that airspace.

Kenneth Gonsalves
ATP. Challenger 850 & Falcon 10
Mississauga ON, Canada


Need to be aware of any discrepancies in our navigation equipment. Therefore, we revert to traditional nav whenever a discrepancy occurs.

Dionicio Pérez
ATP. Citation 650
Zapopan, Mexico


On one occasion, we were at FL430 flying from Baghdad to St Petersburg. As we were crossing into Turkey, we had already had the usual ADS-B fail due to military GPS jamming (being close to Syria). However, shortly after, the autopilot turned sharply right and the route on the MFD disappeared. Our initial action was to go HDG, with a small correction back toward track, and hit the EVENT marker. Then we wrote down all the GPS and IRS positions. We found a large difference in the longitude, so we disabled both GPSs from the FMS, and continued with DME/DME and IRS. We diagnosed that while comparing the positions by plotting all positions written down in the JeppFD Pro map. All 3 IRS were close to each other as well as our plotted track. However, the GPSs were 90 nm west of it. We continued to monitor our track and GPS positions, and a bit later, close to the Black Sea, the GPSs came back to their senses and we enabled them again with the FMS.

Mike Sejourne
ATP. Global Express
Aviation Director & Chief Pilot
AIM Aviation
Montréal QC, Canada