The Reality Behind the Mystery of Indian Air Force MiG-21 ‘Flying Coffins’

A post-mortem of the Indian Air Force’s (IAF) MiG series of fighter jets has come up with shocking revelations pointing to perennial engine oil leaks besides other serious technical glitches that have lent the aircraft notorious distinction of ‘flying coffin’ or ‘widow-maker’ owing to frequent crashes and loss of human lives.

Every MiG crash in the country invited emotional outbursts from public and stinging rebuke from defence analysts, but the incidents were invariably written off claiming them to be human error.

Documents accessed by The Sunday Standard reveal that MiG engines that propelled these roaring fighter jets, once considered backbone of the IAF, are of poor quality. Nearly 40 per cent of these engines and accessories produced by Hindustan Aeronautics Limited (HAL), Koraput, have been returned by the IAF for some or the other defects. HAL is a Navratna company, owned by the government.

 IAF MiG-21 Flying Coffins
 IAF MiG-21 Flying Coffins

The problem ranges from oil leak, metallic particle in oil filters and hot air leak from rear casing to trouble in compressor and even in turbine of MiG-27 aero engines. The defects are scary for the government, which has lost almost half of its MiG fleet to the crashes in the last 40 years, leaving 171 pilots and 39 civilians dead. Although Defence Minister A K Antony had told Parliament last year that both human error and technical defects were responsible for MiG crashes, he conveniently forgot to inform people about horrific condition of government’s state-of-the-art manufacturing unit.

“Most of the cause factors can be classified as defects during manufacturing or overhauling process. IAF has been flagging these issues but government’s response is slow,” said an official on the condition of anonymity.

It is learnt that all three MiGs—MiG-27, MiG-29 and MiG-21—are facing serious quality issues. MiG-27 suffered Low Pressure Turbine Rotor (LPTR) failure in at least 11 recent incidents. The HAL in some cases even lied while overhauling the LPTR, saying it had followed the overhaul manual but Ministry of Defence (MoD) officials said the procedure recommended by the original equipment manufacturer was not being implemented by the celebrated company.

There are more shocking facts conveniently swept under the carpet. The springs installed in fuel pump of MiG 21 engines are failing frequently. A MiG-21 Bison aircraft crashed in November 2012 in Gujarat which was attributed to spring failure.

The documents suggest that of the five main fuel pumps fitted with HAL-manufactured springs, at least three springs failed, which is unforgivable as it would have certainly resulted in accidents. Shockingly, the main fuel pumps of MiG-21 Bison engine continue to leak fuel, despite four studies conducted and implemented since 1990s. It says despite incorporating changes, fuel leak from main fuel pump continued unabated from throttle end.

A senior official said flying operations of MiG-29 fleet are often suspended due to non-availability of critical accessories and poor quality of repairing. Even if one aircraft of the fleet is affected by the snag, the entire fleet is grounded till the problem is identified and resolved.

However, another reason behind the poor quality of production and engine repairs is attributed to mass production work in the last leg of production year, to achieve the target. For example, in the first six months of 2012-13 production year, HAL finished the work on only four MiG-29 engines, but in the last quarter of the year, four engines were completed within three months.

Similarly for MiG-27, the HAL finished the work on nine engines in nine months, but interestingly another nine engines were completed within the last three months. The issue was flagged by the MoD saying such trend is adversely affecting the quality of aero engines.

“HAL is not interested to provide quality engines or repair work to the IAF. They are only interested in meeting the production numbers every year. There is also an impression that the work force in HAL delays the production to last three months to earn few extra bucks for ‘over time’ which is disgusting, given the fact that human lives are at stake,” an official said.