Satellite imagery from March 19 shows one of India’s latest military machines—the multi-mission P-8I maritime patrol aircraft.

The twin-engine planes are variants of the Boeing’s P-8A Poseidon, originally built for the U.S. Navy. As seen in imagery collected by satellite firm Astrium, the aircraft are parked at the Indian naval air station INS Rajali in the southern state of Tamil Nadu.

The P-8Is support various missions for the Indian Navy: including anti-submarine warfare, anti-surface warfare, maritime patrol as well as intelligence, surveillance and reconnaissance missions.

The aircraft will replace India’s ageing fleet of Soviet-era Tupolev Tu-142s, which are also deployed to INS Rajali and subordinate to India’s Eastern Naval Command.

Earlier this month, Boeing delivered the fourth P-8I to India on schedule, fulfilling the first half of a contract for eight aircraft signed back in January 2009. The U.S. plans to deliver the remaining aircraft by the end of 2015.

The imagery shows the completion of an additional apron in February, as well as new construction of four additional shelters. The shelters will probably support the basing of the P-8I—allowing the aircraft to monitor key, strategic locations.

With a maximum range of more than 1,300 miles, the P-8I can easily reach the Andaman and Nicobar Islands, India’s forward position in the Bay of Bengal. In August 2013, the patrol plane IN 321 made its first flight to naval air station INS Utkrosh based on the island chain.

Based on the Boeing 737-800 aircraft, the P-8I have a length and wing span of 39 and 37 meters, respectively. They are equipped with the CAE AN/ASQ-508A magnetic anomaly detection system, APS-143C(V)3 multi-mode radar and an export version of the Raytheon APY-10 surveillance radar.

For armaments, the aircraft has an internal weapons bay housing Mark 54 torpedoes, depth charges and free-fall bombs.

The P-8I also has under-wing hardpoints which can be armed with air-to-surface missiles. In December 2010, India requested the sale of AGM-84L Harpoon Block II anti-ship missiles, which can be fired against land and sea targets.

Beyond capabilities, many analysts point to these aircraft—along with the sale of other American military equipment—as an important factor furthering the U.S.-India strategic relationship. Washington is expected to try and renew ties with India following the election of nationalist and business-oriented politician Narendra Modi to the prime minister’s office.

While certainly military equipment should increase interoperability between the U.S. and Indian militaries, it should be noted that India has yet to sign numerous agreements including the Basic Exchange and Cooperation Agreement for Geospatial Cooperation, the Logistics Support Agreement as well as Communications Interoperability and Security Memorandum of Agreement.

These arrangements tend to be the basis by which the U.S. enhances military ties with other countries. As a result, these agreements may be far more important to watch than the mere sale of defense equipment.