Express consulted several serving and retired Sukhoi pilots, engineers in HAL, current and former IAF officials and even experts with military airworthiness to verify our findings: If Sukhois are exposed to the sun for a longer period, malfunctions will occur without fail. The IAF was contacted for an official response, but shockingly a delayed reply came in just one line. "Maintenance shelters have been procured at our airbases solely on the IAF's initiative and more of these are being procured to cater to the varied environmental conditions of our country," an email reply from IAF media managers said, to our queries.
The IAF operates over 150 Sukhois from its bases in Pune, Barelley, Chabua, Jodhpur and Tezpur. HAL says it had communicated officially to the IAF the need for providing shelters. The matter was also taken up during Quality Assurance meets and Commanders' Conference.
HAL claims that all Sukhois at their Nashik Division (manufacturing base only) are kept under shelters, while the IAF uses canvass covers to protect them from UV rays, rain and dust. "The UV rays will have faster aging and hardening effect on the rubber and other non-metallic parts, which can lead to more premature failure, in the longer run. The canvass can only protect the aircraft from UV rays, but not the heat, which can harm avionics parts," sources said.
A Sukhoi pilot told Express that small dust particles will get deposited on engine blades, if they are exposed to the sun.