In a pivotal moment in the history of the Indian Air Force (IAF), the Number 4 Squadron on Tuesday bid farewell to MiG-21 Bison fighter jets as they flew over Uttarlai at Barmer, Rajasthan for the final time in a show of the force’s bid for indigenisation.In a pivotal moment in the history of the Indian Air Force (IAF), the Number 4 Squadron on Tuesday bid farewell to MiG-21 Bison fighter jets as they flew over Uttarlai at Barmer, Rajasthan for the final time in a show of the force’s bid for indigenisation.