HINDUSTAN FIGHTER HF-24 MARUT
PART I: BUILDING INDIA'S JET FIGHTER
BY K CHATTERJEE
Conceiving the Marut
The pursuit of self-reliance in aviation, led the Air Staff, to issue a requirement for a home-made multi-role fighter aircraft during the mid-1950s. The building of HF-24, or Marut (Spirit of the Tempest), as this aircraft was to be called, was the first attempt of its kind anywhere outside the major powers. At the time of the Marut's conception, the domestic aviation industry's only design experience amounted to the HT-2, a prop trainer. Whatever aircraft manufacturing capability existed resulted from the license production of the Vampire FB Mk.52s and T Mk.55s. To have considered building a Mach 2.0 capable aircraft, given such limited capabilities bordered on audacity.
The Marut was conceived to meet an Air Staff Requirement (ASR), that called for a multi-role aircraft suitable for both high-altitude interception and low-level ground attack. The specified performance attributes called for a speed of Mach 2.0 at altitude, a ceiling of 60,000 feet (18,290 m) and a combat radius of 500 miles (805 km). Furthermore, the ASR demanded that the basic design be suitable for adaptation as an advanced trainer, an all-weather fighter and for 'navalization' as a shipboard aircraft. It was directed that this aircraft be developed within the country. As an aside, it might be worth noting that the design philosophy and ASR for the current Light Combat Aircraft (LCA) is quite similar.
The task of meeting the ASR was assigned to Hindustan Aircraft Limited (now HAL Bangalore). However, in 1955 no infrastructure capable of supporting the programme existed in India. And there was scant appreciation on the part of the government of the technological hurdles that would need to be surmounted. In response to an Indian invitation, Kurt Tank (of Focke-Wolf fame) and his assistant Engineer Mittelhuber, arrived in Bangalore in August 1956. As head of the design team it was Kurt Tank who would give the ASR shape and substance.
The first prototype Marut aircraft. When it was rolled out it carried the Identifying number HF-001 (As seen in top photo). By the time of its first flight it took up the assigned serial BR-462
Hindustan Aircraft, in 1956, possessed only three senior Indian design engineers and the entire design department boasted only 54 personnel. The prototype shop had 60 people on staff and the entire strength of the production engineering department amounted to just 13. Worse yet, no hangar space was available for the construction of prototypes, no machine shop existed for prototype engineering, and there were no test equipment, structural test rigs or a flight test laboratory.
In fact, the Hindustan Aircraft complex lacked even a suitable runway from which the new aircraft could begin flight testing. The entire infrastructure had to be built from scratch. Much effort was invested in building up a viable design and testing infrastructure. And by the time the first prototype of the Marut commenced its flight test programme in 1961, Hindustan Aircraft employed 18 German design engineers, a design department possessing 150 personnel, a prototype shop with 631 personnel including 39 supervisors, and a production engineering department with more than 100 personnel.
Building the Marut
Work on designing the new "Hindustan (Indian) Fighter" commenced in June 1957 and the aircraft was awarded the HF-24 designation. A full scale representation (wooden glider) of the projected fighter was ready by early 1959, less than a year after the last mock-up conference on 10 April 1958. A test program was initiated with this glider on 1 April 1959 by Wg. Cdr. Suri and Wg. Cdr. (later Gp. Cpt. retd.) Kapil Bhargava. The two-seat glider was towed by a C-47 Dakota and usually released at altitudes of between 12,000 and 15,000 feet (3660 and 4570 m). By the end of this phase of the programme on 24 March 1960, the glider had completed 78 flights. Assembly of the first HF-24 prototype (HF-001) began in April 1960, and eleven months later, on 11 March 1961, powered taxiing trials were initiated.
BD-845 was the second production HF-24 which joined the No.10 Squadron in 1967.
The flight development team was headed by Wg. Cdr. Das who in turn was assisted by Sqn. Ldr. I.M. Chopra, largely responsible for stability trials, Sqn. Ldr. W.M. Tilak for armament and instrumentation development, and Sqn. Ldr. Dey whose concern was primarily with power plant development.
Search for a Suitable Engine
The design of the HF-24 had been based around the availability of the 8170 lbs. (3705 kg) afterburning Orpheus BOr 12 engine. Unfortunately, the British requirement for this powerplant was discarded and the Indian Govt. declined to underwrite its continued development. In retrospect, this was a very shortsighted decision on the part of the Indian Government. The manufacturer had asked for £13 million as development costs, not a large sum even by the standards of the 1960s. And the Government's decision not to underwrite the costs of the BOr 12 development was to haunt the Marut programme for ever. In the even that the BOr 12 was no longer an option, the design team was forced to adopt the non-afterburning 4850 lbs. (2200 kg) Orpheus 703 for the initial and interim version of the fighter. India now initiated what was to prove a lengthy and frustrating search for an alternative power plant to the Orpheus BOr 12.
In 1961 the MoD approached the Soviet Government with a view to the acquiring the Tumansky RD-9F, a small-diameter axial-flow afterburning engine used in the MiG-19SF fighter. Six RD-9Fs were imported late in 1961 and bench-tested at Bangalore. Discussions were held in Moscow during July 1962 over licence manufacture of this turbojet for the HF-24. In the end this came to nothing. The RD-9F was finally rejected in 1963 on the grounds that it was prone to surging. Furthermore, its overhaul life was unacceptably short and there seemed little likelihood of its compressor being developed beyond its Mach 1.4 stress limit, and negotiations with the Soviet Union were accordingly discontinued.
Rather than shelve the entire Marut programme, the Indian Government decided to order 18 pre-production aircraft powered by the Orpheus 703 in late 1962. The pre-production batch was followed by 62 similarly powered production examples, despite the lAF's initial reluctance. The IAF's reluctance stemmed from the fact that Orpheus 703 powered Marut offered only marginal improvement on the Hunter's performance. And the air force's reluctance contributed to the aircraft's protracted delivery schedules.
The Indian Government eventually became disenchanted with the entire programme and on 1 July 1969, the Indian test team was recalled from Egypt. The test aircraft, however, was presented to the Egyptian Govt. Meanwhile Bristol Siddeley proposed in 1964 to marry the high-pressure inner spool of the Pegasus to the Indian-manufactured Orpheus 703, thereby theoretically offering a performance similar to that anticipated from the abandoned Orpheus BOr 12. But the Indian Govt. was again reluctant to underwrite development costs.( money games) The issue was also somewhat confused by Indian hopes that the US government would provide support for the HF-24 programme.(more games) In 1964 U.S. technological aid was formally requested to help with the development of a suitable power-plant for what was to be the HF-24 Mk 2. In the event, the possibility of US aid was delayed by Indian negotiations with the Soviet Union for a MiG-21 manufacturing licence and was finally abandoned as a result of the Indo-Pakistan conflict in September 1965.
Marut joins the IAF
The first pre-production HF-24 Mk1 (BD-828) made its initial flight in April 1963 and was joined by BD-829 and BD-830 within the year. Two of the pre-production Maruts were handed over to the IAF at a ceremony on 10 May 1964 at Bangalore and taken over by the IAF's Aircraft & Armament Testing Unit (AATU). Joined by more pre-production Maruts, these aircraft underwent service and weapon system trials (the latter at the Armament Firing Wing at Jamnagar) for nearly three years before being suitably updated.
The armament comprised 4 powerful 30mm Aden Mk.2 cannon with 130 rds/gun and an internally-housed MATRA Type 103 rocket launcher modified to accommodate 50 68-mm unguided rockets in 10 rows of five rockets each. The aircraft had four underwing hardpoints each stressed to carry 1000 lbs. (454-kg) bombs, napalm canisters, Type 116 SNEB rocket launchers, clusters of T10 air-to-ground rockets, or 100 Imp Gal (454 L) drop tanks. When production ceased, the Marut had around 80% indigenous content and all components were being manufactured by Hindustan Aeronautics.
The Marut was a robust aircraft with extremely good visibility for the pilot, and was aerodynamically one of the cleanest fighters of its time. With a very stable platform, the aircraft required no artificial augmentation or auto-stabilization. The Marut was originally to have been stressed to 10.5g but 8g was eventually considered to be adequate for the production model. The controls were provided with artificial feel and were effective over the entire speed range, the top limit being 620 knots (1149 km/in) IAS at sea level.
Continued Development
The search for a suitable engine continued even after the Maruts went full ops.......
If we recall the development cycle LCA in place of Marut, the story is very similar.
Govt. was not able to negotiate an engine development contract for kaveri engine on time, and also like Marut , LCA's development was also delayed because of US sanctions
Austin wrote:
From what I have read the decision to buy Mig-29 was a hasty decision , the M2K decision was a well thought off one albeit an expensive fighter for its time but there was nothing better that would match F-16 then and Mig-29 existed as some ram-L for NATO in secret SU airbase.
The deal was to buy 40 M2K with lic production of 140 odd fighter in India which if we had pursued there would not have been a need to go for MMRCA for some unknown reason it was not pursued and Soviet chipped in with Mig-29 with lic production for the latter in similar number ( perhaps the M2K deal got scuttled under SU pressure ) ofcourse soon came the 90 india went bankrupt and SU collapsed and rest is history.
The reason was simple that they wanted to buy more aircrafts not to develop indigenous capabilities,for some unknown reasons that haunt arms dealers and politicians..
Those who do not learn from history are doomed to repeat it.-George Santayana
Such things will happen again and agin when profit making becomes more attractive than National security, and stable minded people are not directing the project inplace of corrupt politicians and stone headed beaurocrats.
) . But the only country we should compare ourselves with is the US . And what can be done to bring ourselves to there level .
And absolutely true.