Owing to the mid-air engine trouble in IAF’s Sukhoi-30MKI fleet lately, the fighter jets will be modified now under new specifications laid down by its manufacturers, Sukhoi Design Bureau. The modification will be carried out on 400 engines of the twin-engine aircraft, besides installation of some spares for emergencies. The IAF has a fleet of 200 Sukhoi aircraft and another 72 are on order. The manufacturer will install modified engines on the next 72 jets as well. The modification will primarily be carried out at HAL’s Sukhoi engine plant in Orissa. The refit will be carried out in batches over the next 18-24 months.