The much-awaited test launch of the air version of the BrahMos supersonic cruise missile has been further delayed and now India hopes to undertake the drop trials by December 2013 .

India had planned to conduct the test launch by December 2012. The development of the missile is already over three years behind schedule.

“Various tests for fitting the air variant of Brahmos onto the Sukhoi aircraft of Indian Air Force (IAF) are being undertaken and the entire work is expected to be  completed [only] by the end of 2013, when we will be ready to launch the supersonic missile for the first time from air,” says a senior defense ministry source.

The initial test firing of the air-launched missile, being developed in cooperation with a Russian agency is likely to be undertaken from the Sukhoi-30 MKI aircraft.

“Since it has to go for a fitness test on Sukoi-30, it would take time to conduct such trials and the new version would be launched within a year,” Air Chief Marshal N.A.K. Browne told reporters earlier this month.

According to the source, the air variant BrahMos has to weighs half a ton less than regular missiles.

The air variant will feature just one booster instead of two to accelerate the missile to its supersonic cruise speed, when a ramjet engine takes over. Also, a new take-off engine for launching the missile on air and at extreme high altitudes is being developed.

Moreover, the Super 30 variant of the Su-30 is being developed to help launch the BrahMos missile from an underbelly pylon. 

India’s state-owned Hindustan Aeronautics Limited (HAL) is making the necessary modifications to strengthen the undercarriage of the Sukhoi to enable the aircraft to take-off and land with the missile, the source says.

Two IAF Su-30MKIs are being modified by HAL at its Nashik facility for integration with the aerial launcher.

With a top speed of Mach 2.8 and range of 290 km (180 mi.), the missile can carry a conventional warhead of up to 300 kg (660 lb.) and engage targets at an altitude as low as 10 meters at nearly three times the speed of the U.S. Tomahawk cruise missile.

The two-stage missile already has been inducted into the Army and Navy. A submarine launch version is in the final stages of trial.

India recently asked Russia to induct the BrahMos supersonic cruise missiles into its naval fleet to further strengthen the joint venture between the two countries.

In October, the Indian government had cleared a proposal worth over $1.2 billion for purchasing, testing and integration of at least 200 BrahMos missile on the Russian-made Su-30MKI aircraft in the IAF fleet.

India and Russia discussed the deal during the Dec. 24 visit of Russian President Vladimir Putin to New Delhi.

An agreement also was signed among BrahMos Aerospace, Russian Rosoboronexport and Sukhoi Design Bureau to develop the air-launched version of the missile.

Founded in 1998, BrahMos Aerospace Ltd., a joint venture between India’s Defense Research and Development Organization and a Russian military consortium, builds the BrahMos supersonic cruise missile based on the Russian-designed NPO Mashinostroyenie 3M55 Yakhont.