India's Mighty Su-30MKI Fighter Jets Have a Big Problem

By Thomas Newdick

In the past decade, the Indian Air Force has bought hundreds of Su-30MKI fighter jets from Russia. Some of Moscow’s most advanced export fighters, the warplanes should have helped New Delhi strengthen its military.

But it turns out, the twin-engine jets have failure-prone motors. Their AL-31FP engines break down with alarming frequency.

In March, Indian defense minister Manohar Parrikar revealed the propulsion problems.

There have been no fewer than 69 investigations involving engine failures since 2012, according to Parrikar. Between January 2013 and December 2014 alone, the Indian Air Force recorded 35 technical problems with the turbofans.

A shortfall in India’s Sukhoi fleet is a big deal. Especially at a time when India’s fighter squadrons are shrinking, and plans to induct the French Rafale fighter have stalled.

The Su-30MKI remains the pride of the Indian Air Force. Russia’s Irkut Corporation initially supplied the jets, and today Hindustan Aeronautics Limited produces them under license.

It was on New Delhi’s behest that Russia revamped the Cold War-era Su-27 into this modern “superfighter,” with thrust-vectoring engines, canard foreplanes, a digital fly-by-wire flight control system, electronically scanned radar and air-to-ground weapons.

India had to wait until 2002 before it started to receive the Su-30MKI in the form it had originally requested. The Air Force is set to receive 272 Su-30MKIs.

India also bought 18 austere Su-30K fighters without the multi-role capabilities or thrust-vectoring engines.

Of the Su-30MKIs, Russia has delivered 50. HAL is producing the rest at its Nasik facility, where aircraft continue to roll off the line. With around 15 to 20 aircraft handed over every year, the current orders are set to finish around 2019 or 2020.

So what exactly is wrong with the engines? We have a pretty good idea.

Parrikar attributed the failures to faulty bearings that contaminated the plane’s oil supply. It seems that metal fatigue led to tiny pieces of metal shearing off the friction-reducing bearings, which then entered the oil system.

This accounted for 33 of 69 engine failures.

Another 11 failures were the result of engine vibrations, while eight more arose from a lack of pressure in that same lubricating oil. New Delhi has not revealed the cause for the remaining 17 incidents.

The Air Force responded by taking the issue up with NPO Saturn, the Russian manufacturer. According to Parrikar, the company has come up with nine different modifications to help solve the problems.

India has already incorporated these “fixes” into 25 engines built at its plant in Koraput. In the future, the engines should benefit from an improved lubrication system, superior-quality oil and bearings that are a better fit.

However, a more general worry for the Air Force is the poor serviceability of the Su-30MKI fleet — meaning the number of aircraft actually available for operations on a daily basis.

Based on figures given by Parrikar, only 110 Su-30MKIs are “operationally available.” From a total of more than 200 aircraft that Irkut and HAL had delivered by February 2015, that means 56 percent are ready at any given time.

India’s Su-30MKI fleet has suffered five crashes since 2009.

To be sure, it’s not a great record, but it’s also not notably bad — especially when compared with the attrition rates of the Indian Air Force’s older fighters. It’s unclear what role, if any, the engine problems played in these accidents.

What’s perhaps more significant is the fact that engine deficiencies have bugged the Flanker from the start.

“The initial batch of 18 Su-30Ks and 10 Su-30MKIs were grounded as a result of engine issues, that were subsequently put down to design problems,” Indian defense blogger Shiv Aroor wrote.

1 | 2 | Next Page››

This article first appeared in War Is Boring here

Thomas Newdick
Author Archive