India's state-run Hindustan Aeronautics Ltd (HAL) will build trainer aircraft to train pilots fly the Tejas multi-role combat aircraft

"The two-seater Tejas trainer aircraft are not expected to be delivered before 2021. The process of building the trainers hasn’t yet started," Hindustan Times quoted a senior ministry of defence official as saying.

Currently, the Indian Air Force (IAF) has 11 Tejas fighter jets and is likely to receive five more by March this year. Training of pilots to fly the Tejas is now restricted to simulators and a couple of “instrumented aircraft” with the Aeronautical Development Agency (ADA) which is an arm of the Defence Research and Development Organisation (DRDO), Hindustan Times reported Wednesday.

“An instrumented aircraft is not a standard version of the aircraft. For instance, the instrumentation panel in an instrumented aircraft is not standardised,” the report quoted a senior IAF officer as saying.

"It is a prototype and requires a high degree of skill to fly. It is only used to test an aircraft, it is difficult to train new pilots in these jets,” the officer added.

The simulators and instrumented aircraft are owned by DRDO, based in Bangalore city.

"The IAF can only use the aircraft when they are not being used by the DRDO. Trainers are generally collated with the squadron," a senior test pilot of the IAF said.

Senior HAL officials confirmed that trainer jets for the Tejas aircraft aren’t yet ready.

The IAF ordered 20 fighters with Initial Operational Clearance (IOC) and another 20 with Final Operational Clearance (FOC).

The first contract for 20 jets under IOC configuration was signed in 2006. All 20 fighters including the trainers were to be delivered by 2011. The contract for 20 fighters under the FOC configuration was signed in 2011 with a similar delivery schedule.

"Of the 40 aircraft, eight were to be fighters to train pilots. In addition, the IAF will buy another 83 Tejas fighters from HAL. The technical evaluation of the 83 fighters is complete. Much of the price negotiations are also in process,” Hindustan Times quoted another source as saying.