AirNav Confirms Navigation Signal Interference Has Been Addressed

The State-Owned Enterprise LPPNPI, or AirNav Indonesia, has spoken out on reports of GPS signal disturbances on aircraft that have been the subject of public discussion. AirNav Indonesia says the phenomenon is known in international aviation as GNSS RFI (Radio Frequency Interference).

“Addressing GNSS RFI is one of the global safety agendas championed by ICAO (International Civil Aviation Organization). In this regard, AirNav Indonesia has anticipated this by implementing comprehensive standard procedures,” said AirNav Indonesia President Director Avirianto Suratno in a statement on Thursday (21/5/2026).

Avirianto explained that modern aircraft navigation systems rely on the Global Navigation Satellite System (GNSS), operating by receiving signals from satellite constellations orbiting the Earth. The accuracy and integrity of these signals are enhanced through augmentation systems consisting of Aircraft-Based Augmentation System (ABAS), Ground-Based Augmentation System (GBAS), and Satellite-Based Augmentation System (SBAS).

Signals reaching the Earth’s surface operate at low power, so the system is designed to be layered with augmentation technology to maintain accuracy and integrity under various on‑the‑ground conditions.

“Radio frequency disturbances from various sources to these signals are technically referred to as GNSS RFI,” said Avirianto.

According to him, ICAO has made GNSS RFI a priority safety agenda for global aviation in recent years. The world aviation body has issued international standard procedures for member states to detect, report, and respond to GNSS interference.

ICAO, further Avirianto, also recommends that countries maintain terrestrial navigation infrastructure as a complementary layer to GNSS.

“Indonesia has adopted the GNSS RFI framework in its national aviation regulations. AirNav Indonesia, as the provider of aviation navigation services across Indonesian airspace, has implemented this provision fully in daily operational activities,” explained Avirianto.

Integral Components of the Aircraft Navigation System

He elaborated that AirNav Indonesia operates a complete network of terrestrial navigation infrastructure across Indonesia, comprising three main facilities. These facilities are spread across Jakarta FIR and Makassar FIR, covering major airports to remote areas throughout the country.

The three facilities include Very High Frequency Omnidirectional Range (VOR), a ground-based radio signal transmitter operating up to 200 Nautical Miles. This facility operates independently of satellite signals.

“AirNav Indonesia currently operates DVOR (Doppler VOR), which offers higher accuracy than conventional VOR,” added Avirianto.

Another major facility is Distance Measuring Equipment (DME), which provides real-time information on slant distance or the direct line-of-sight distance between the aircraft and the ground station. When operated co-located with VOR to form a VOR/DME pair, the system yields a complete position fix based on azimuth and distance.

“Then there is the Instrument Landing System (ILS), a precision approach and landing guidance system that operates independently of GNSS. The ILS facilities comprise the Localizer (horizontal guidance) and Glide Slope (vertical descent guidance),” continued Avirianto.

Four Standard GNSS RFI Response Steps

AirNav Indonesia has established GNSS RFI operational procedures that refer to ICAO standards and are consistently applied across all air traffic service units. Step one is early detection. In this phase, air traffic controllers (ATC) actively monitor radar screens and are trained to recognise misalignments between aircraft navigation systems and radar surveillance. Pilots also report directly if they detect anomalies in the cockpit navigation system.

Step two is coordination and escalation. When GNSS RFI is detected, ATC immediately coordinates with the affected aircraft, forwards information to nearby ATC units and adjacent FIRs, and documents all events for reporting to the Directorate General of Civil Aviation of the Ministry of Transport.

In parallel, AirNav Indonesia also coordinates with the Ministry of Communications and Digital (Komdigi) through Balai Monitoring Spektrum Frekuensi Radio (Balmon) for tracking and taking action against interference sources.

Step three involves transitioning to terrestrial navigation systems. ATC provides direct radar-based navigation assistance via vectoring, then shifts to terrestrial navigation layers. The transition to VOR, DME, or ILS is performed smoothly without operational interruption so that aircraft can conduct approaches and landings safely.

The next step is to issue a Notice to Airmen (NOTAM) after GNSS disruption is verified. NOTAMs are released to raise awareness among all pilots and reported to ICAO through international GNSS RFI reporting mechanisms.

Cross-Sector Coordination

Effectively addressing GNSS RFI requires cross-institutional collaboration. AirNav Indonesia maintains close coordination with the Directorate General of Civil Aviation, the national aviation authority, and Balmon, as the frontline for detecting and acting on interference sources on the ground. The two fronts operate simultaneously and in concert to ensure national aviation safety.