Since the development history of the Tejas was very long, the detail design was fixed long ago. Defence requirements are dynamic & keep changing every few years. To meet the new requirements in the older airframe, Mk1A version is under development.
HAL has released very little information about this aircraft but from what we know it is going to be much improved than the FOC version of the Tejas Mk1. IAF has agreed to induct 120 Agile MK1-A Aircraft .
The major improvement is in terms of weight savings. The nose & wings of the current version of Tejas have dead weight acting as ballast to balance the aircraft. Also the main landing gear is “over-engineered” and hence heavy. In the Mk1A version of the aircraft the landing gear design will be optimized & the ballast weight is reduced. Total weight saving of 500 – 1,000 kg is envisaged. For a aircraft weighing 6,560 kg, this is a very significant amount of weight.
The capability to fire the ASTRA missile along with I-Derby-ER missile. Meteor Missile will NOT be integrated as clearly stated by MBDA, France.