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HAL Proposing Upgradation Of IAF's Avro HS-748 Transport Aircrafts?


Jun 24, 2012
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HAL Proposing Upgradation Of IAF's Avro HS-748 Transport Aircrafts?


The Hindustan Aeronautics Limited [HAL] recently issued a 'Request For Information' [RFI] for a proposal to replace the Gas Turbine-powered turbo-prop engines of the Indian Air Force's [IAF] Hawker Siddeley's Avro HS 748 medium-lift transport aircraft. It seeks to replace the currently used British Rolls-Royce Dart 533-2 & 536-2T engines, which HAL license-built, with a modern solution that churns out more power, demonstrates better fuel efficiency1, and also weighs less & has dimensions no bigger than the ones presently used. To get an idea of how old the engines & the aircraft it powers are, the engine has already found its way into HAL's Heritage Museum, its manufacturer in India, even as it powers this IAF aircraft, as of today.


Any change of Engine would also likely require change to systems connected to it, like the Gear Box transferring power to the aircraft's auxiliary systems, like Cabin Supercharger, Tachometer, Generator etc, possibly requiring their replacement too. HAL, over the past one year, has been issuing similar notification soliciting 'Expression of Interest' for other sub-systems for incorporating into this aircraft, like improved Autopilot system & Weather Radar, fitting it with Multi-Function Display [MFD] & Flight Data Recorder [FDR], that would, no doubt, lessen its obsolescence.

HAL states that 59 flight-worthy HS-748 airframes in the country, have notched relatively fewer flying hours of around 350 hours/annum & have, thus, substantial residual life of around 80,000 hours to warrant such an upgrade. The HAL website informs of already having carried out a limited upgrade of its Navigation & Communication systems. However, given the nature of systems, like its engine & radar, that is sought to be replaced this time, one could infer that this possible life-extension move aims to prolong its use much beyond 2020, when it was expected to cease service with the IAF. 59, actually 56, is also the number that is sought to be replaced. So essentially, HAL is asserting that entire fleet of these IAF aircrafts have sufficient life left in them, so as to preclude any replacement plans. This being the case, it raises an interesting question. One has been reading reports suggesting a move to replace these aircrafts, designed in the 1950s, with a contemporary solution. In fact, as being bandied, it would have been a showcase project, of sorts, wholly undertaken by the country's private sector, with no involvement of the state-owned monopoly, the HAL, in the production process. However, given the stifling nature of current policies governing domestic Defence production, & the military's habit of placing orders in a piecemeal manner, that wouldn't afford first-time manufacturers the benefit of economies of scale, this move to let India Inc. handle the project hasn't been met with the kind of enthusiasm GoI had hoped for. No reports in the MSM to suggest any forward movement on this front.


This HAL-issued notification also leads one to ask if the IAF is already on board this proposal, or whether HAL hopes to sell this idea to its captive customer, once it itself is suitably confident of its viability. If one were a betting person, one would bet money on the fact that it is the latter. For one, there are no reports presently in the MSM that indicate any intent to go the upgrade route. With the Govt already having decided to let the private sector handle the Avro-replacement project, HAL would essentially be bereft of any share in this pie, if the proposal does see fructification. Thus, it would make great sense for it to extract maximum possible mileage from this aircraft, which it license produced, by prolonging its use with the IAF, possibly even scuttling the original one. Not factoring in maintainability of a vintage system, the economic cost of this upgrade is likely to be much lower than building a new air frame from the ground up. Given the recent depreciation of the Indian Rupee. that continues, any proposal that promises to lessen the burden on the state exchequer is likely to get a sympathetic hearing too. Going in HAL's favour is also the, aforementioned, near non-response from India Inc.. Any such HAL intentions is presently at a preliminary stage, as it has only just issued a RFI.

One of the requirement that stands out is the need for one of the engines to operate in "Hotel Mode" - keeping one of the engines running when the bird is on the ground, but preventing propeller movement, for powering the HS 748's electrical systems, even when not flying. This function is normally performed by an Auxiliary Power Unit [APU]. The HS748 is believed to be fitted with a British Rover Company-built small Gas Turbine engine for this purpose. Use of the aircraft's main engine in 'Hotel Mode' precludes the use of an APU, leading to weight savings. However, its use in this manner poses some significant drawbacks. Most obvious one among them being the differential wearing of the engines, the one used for this purpose would fail faster. Besides this, it also poses certain operational hazards. Considering that the propeller is prevented from rotating using a braking arrangement, failure of the brake would lead to a catastrophic situation if there are human presence in the vicinity at that moment. It would, therefore, require adoption of Standard Operating Procedures [SOP] that address this hazard. It is thus a trade-off between a less hazardous work environment or weight saving, something HAL would surely have given sufficient thought to prior to stipulating such requirement.

Coming back to the issue at hand, that of upgrading this aircraft, it surely is an interesting proposition, though one can't say one agrees with the proposal, in the limited amount of time one has thought about it. Ensuring continued reliability & maintainability of an aircraft is an equally capital intensive proposition, whose value piles up through the passage of time. This is especially true for a legacy platform such as the Avro HS-748. Present financial conditions permitting, It would be much more prudent & cost-effective, in the long run, to operate a modern aircraft, instead of flogging an old horse, however well-rested it is claimed to be. As rightly envisaged by the Government, this Avro replacement program is an ideal springboard for adding capacity & building capability in the private sector, boosting indigenous production, spurring healthy competition, breaking the shackles of monopoly of state-owned DPSU, all leading to a satisfied & confident customer - the Indian Armed Force. The Government would be well-advised in expending its political capital in ensuring that the original programme gets off the metaphorical ground & all HS-748 aircrafts are honourably retired, before they begin acquiring notorious reputations.





Link - http://www.aame.in/2013/08/hal-proposing-upgradation-of-iaf-avro.
Chalo ji.............HAL gets a new screwdriver contract for assembling stuff.....what more do they need??

If private industry comes,what will HAL do?

By the way the bone of contention was,if i remember the very few number of aircrafts in the tender process giving private companies no incentive in setting up facilities for repair
Chalo ji.............HAL gets a new screwdriver contract for assembling stuff.....what more do they need??

If private industry comes,what will HAL do?

By the way the bone of contention was,if i remember the very few number of aircrafts in the tender process giving private companies no incentive in setting up facilities for repair

'IAF flagged MiG issues, but government response is slow' - The New Indian Express

BTW if our Govt. does not want to privatise HAL or not allow any private player in Aircraft making, why does not the Govt. set up another PSU like HAL to compete with HAL? For example in Soviet Union there were Mikoyan, Sukhoi, Yaklov, Tupelov etc.
Yes thats the least the govt can do...........but if they set up more competition where will the corruption moolah come from.God knows how many billions have disappeared in drdo and hal
Idiots cant even write properly in Hindi,,,"

Bharatoy vathu sena.. :hitwall:

Bharatiya Vayu Sena ,,:tup:
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