GSAT-5P (INSAT-4D) was an Indian communications satellite developed by the Indian Space Research Organisation (ISRO) as part of the INSAT/GSAT series. The satellite was intended to provide telecommunications, television broadcasting, and VSAT services across India, helping to strengthen the country’s space-based communication infrastructure.

The satellite was scheduled for launch on December 25, 2010, aboard a GSLV-F06 (Geosynchronous Satellite Launch Vehicle) from the Satish Dhawan Space Centre (SDSC), Sriharikota, India. GSAT-5P was designed to operate in geostationary orbit (GEO) and was based on ISRO’s I-2K satellite bus.

GSAT-5P carried a C-band communication payload, supporting a wide range of applications including:

• Television broadcasting and DTH services
• Telecommunications and enterprise connectivity
• VSAT and network services across India

However, the mission ended in failure shortly after liftoff. The GSLV-F06 rocket experienced a structural failure approximately one minute into flight, leading to the loss of the launch vehicle and satellite.

Despite the unsuccessful launch, GSAT-5P was part of ISRO’s ongoing efforts to expand and modernize India’s satellite communication capabilities. The mission also provided critical lessons that contributed to improvements in the GSLV launch vehicle program and future mission reliability.

Overall, GSAT-5P (INSAT-4D) represents a significant, though unsuccessful, step in India’s development of geostationary communication satellites and launch systems.