Sunday 11 July 2021

Some questions on re-engineering the HF 24 Marut

There has been a lot of twittering about the pros and cons of reviving the Marut. Many of the doubts raised and comments made were by people who had evidently not read what was being said. Dr. Sastry, however raised some questions which I elaborate here. Dr. Sastrys questions I have put in bold.

Would the engine issue not crop up again unless we can somehow use the Adour for which we seem to have the skills to make currently? The original Orpheus is probably to be ruled out?

My view is that Orpheus was orphaned at birth. This engine is cheap, simple and easy to recreate. Getting 30kN from a basic Orpheus should be a given. From my Industry experience I know how sensitive turbomachinery is to small improvements and, conversely, small carelessness’s. You will note that I have said that there are 4 foreign engines available this means that the Adour /Honeywell F124 are in my mind.

You say that India's ability to make composites is suspect - I am guessing that this is because of the need to import the fabric? But then - for all the new avionics there will be a need for multiple composite panels, which means cutting of aluminum and placing the sensors and panels in various places?

The first block of fighters can use composites for access panels and if necessary no composites. The decision to use metal - in the first block - is based on the need for speed, low capital expenditure, the need to do something about building up the air strength.  and the need to use the expertise of our automotive sector as some of the many factors for this decision. Composites -certainly- but when we have the leisure after giving the Air Force a workhorse aeroplane. You note that as per my estimates will save perhaps 200 - 300 kgs at most in an airframe of the size of Marut.  Why put the first flight date at risk? I can save that much by other tricks. In addition we will need to keep the aatmanirbhar angle in mind. We have to work out the supply chain security.

Also I expect some kind of AESA a la Darin III will require a reconfiguration of the nose?

3. Why? Certainly the radome material will have to be quartz or whatever but don't be surprised if I tell you that the existing HF 24 nose contour can accommodate a bigger antennae than the Tejas if that is what you are thinking of.

Removing those guns is a good idea. But carrying 2 more guns outside may be unnecessary in this day and age.

4. Anybody who has deleted guns had later to scramble to find space for them in an already packed airframe. Always a wearisome chore.

It (the Jaguar) will continue to be useless in the mountains as it was in Kargil. Would the new Marut be able to take on that role?

5. The Jaguar's strongest point is that the airframe is there! Otherwise it is second best to the Super Marut. The Jaguar was designed for "low and cool" conditions. It runs out of breath in "hot and high". The HF 24 re-engineered carefully and with love will be much better because the HF 24 has more wing area and less drag.

Finally conventional thinking cannot work when the Air Strength is dwindling despite the Air Forces best efforts. How many squadrons will we have by, say 2025? We are now in a situation we need both the LCA and also the HF 24 Super Marut. Can anyone say how many Tejas aircraft we will get in this year with any certainty? Statistics indicate about two. Given the state of affairs the HF 24 is a “war emergency “solution. If we dilly dally we will soon have no time for war emergency.

This does not answer all questions but it is an indicator of the various non-analytical factors that come into play. I will post this on my blog. You are free to use it for discussions.

 

Prodyut Das 

Engineer and Professor