Vistara is inducting six planes, including four Boeing 737s, to fuel its expansion plan. The Boeing 737s were earlier flown by Jet Airways and will have two class configuration (12 business and 156 economy seats).

Vistara currently operates 22 Airbus A320 planes. The four leased 737 planes will join its fleet in May and two A320Neo aircraft will join in second half of 2019.

According to sources, Vistara will use the planes on domestic routes and will open three new destinations.

“Our focus on serving the domestic market has remained unwavered even as we prepare to become an international airline. These leased aircraft will be deployed to meet the sudden drop in capacity in the market and to aid convenience of travellers. Our decision to induct a different aircraft type in our fleet is a carefully evaluated one, which is both, economically and commercially viable, and will eventually help us take the Vistara experience wider and deeper across markets in India,” Vistara CEO Leslie Thng said.

Vistara operates an Airbus A320 fleet in a three class configuration which also includes a premium economy cabin. It has opted to go for mixed fleet following the collapse of Jet Airways which opened up growth opportunities for rival airlines with access to slots, planes, pilots and trained manpower.

Vistara said it has hired around 500 ex-employees of Jet Airways, including pilots, cabin crew, engineers and other staff.

"Inducting Boeing 737s and hiring ex-Jet Airways pilots enables Vistara to immediately increase capacity. It also helps them overcome growth challenges caused by pilot shortage. However, it will lead to an increase costs. A mixed fleet also has other operational challenges like maintenance, customer satisfaction and ability to swap aircraft on routes," said Ameya Joshi, founder of aviation blog, NetworkThoughts.

SpiceJet has already inducted over fifteen Boeing 737s flown by Jet Airways. It plans to induct 50 planes in 2019, the airline's chairman Ajay Singh wrote in a staff email on Friday.

"In the last three weeks alone we have added 21 planes to our fleet - adding a plane every day. Nowhere in the world has an airline expanded at this pace, increased capacity and added new stations and flights as SpiceJet has done in last one month," Singh said.

The airline also aims to operate on medium and long haul routes and ground work for same is underway, he added.