If satellite-based navigation is more efficient, why do ground-based navaids remain essential?

In an increasingly complex global environment, reliability and resilience in air navigation have never been more important. As geopolitical tensions rise, the aviation sector faces new operational challenges and proven technologies that ensure continuity of operations are critical.

Satellite-based navigation systems (GNSS) provide clear advantages, such as optimization of flight paths, which results in reduced travel times, lower CO2 emissions, and decreased operational costs. However, they are not immune to disruption. Jamming and spoofing incidents have highlighted the importance of maintaining robust, independent navigation infrastructures.

In this context, ground-based navigation aids, commonly known as navaids, continue to deliver reliable, predictable performance and remain a vital part of modern air navigation.

The synergies of ground-based navigation and GNSS

Ground-based navaids and GNSS are not competing technologies. In many countries where GNSS has been implemented, they are expected to operate side by side for decades to come, forming a layered and resilient air navigation environment. This complementary approach enhances safety, availability, and operational confidence, ensuring that navigation services remain reliable even when satellite signals are degraded or unavailable.

For decades, ground-based navigation aids have formed the backbone of safe and reliable air navigation. They are valued for their long operational history and reliable performance, even in the harshest climates. These characteristics make them well suited to both civil and military aviation environments, as well as to airports with demanding operational conditions.

_{Instrument Landing System (ILS) by Indra (Picture by Allan Klo)}

Ground-based navaids provide:

• Proven reliability in all weather conditions
• Predictable and cost-effective performance
• Essential backup capabilities that strengthen airports’ operational resilience

Together, these benefits support operational continuity and help safeguard air navigation services across the globe.

_{VHF Omnidirectional Range (VOR) by Indra}

Indra’s leadership in ground-based navigation

Indra is a trusted global provider of ground-based air navigation systems, offering a comprehensive portfolio that includes:

• Instrument Landing Systems (ILS), including the market-leading Normarc ILS
• Distance Measuring Equipment (DME)
• VHF Omnidirectional Range (VOR) – including Doppler VOR (DVOR) and Conventional VOR (CVOR)
• Tactical Air Navigation (TACAN) in fixed-based, man-portable and shipboard versions

_{Tactical Air Navigation (TACAN) by Indra}

All systems are designed to meet international standards while ensuring long-term reliability, maintainability, and operational stability. In total, Indra has delivered more than 8,000 air navigation systems to180 countries all around the world. The systems are used in the most complex and busy airports, as well as in remote locations with harsh weather conditions.

_{Distance Measuring Equipment (DME) by Indra}

Expertise beyond technology

Beyond technology delivery, Indra has wide competence and expertise in air navigation systems. We can support customers in defining cost-effective and operationally stable navigation solutions. By carefully assessing site-specific requirements and operational needs, Indra helps customers build resilient navigation infrastructures that ensure safe air operations today.

In addition, Indra provides comprehensive technical training to equip the customers with the skills and competence required to ensure effective system operation and maintenance. Our proven ability to efficiently manage projects of varying complexity, from small deliveries to comprehensive turn-key projects, highlights our dedication to providing seamless, end-to-end services for our clients.