Organisation Name: Hindustan Aeronautics Limited

Project: Implementation of Manufacturing Process for Arrester Hook Platform LCA Navy Aircrafts

Introduction

The LCA-NAVY is India’s first indigenously-designed aircraft that is able to execute an aircraft carrier landing. The AHS System drives an aircraft’s ability to be able to do so. The arrester hook is critical to this function and it needs to be able to successfully withstand an arresting load that is between 4 to 4.5 times the landing weight of the aircraft and it has to be reacted at the attachment points of the airframe.

Problems

The functionality and efficiency of the AHS System is dependent on the AHS Platform. The AHS Platform is responsible for the functioning of the entire AHS system in the aircraft. Manufacturing these components is an exact science and the minutiae are critical to the aircraft’s functioning and safety. The dimensions of these components can spell the difference between a successful AHS System or a disaster. Systemic failure or flawed parts can result in untold damage and destruction, which is why perfection in manufacturing standards is a non-negotiable need. Given the highly-sensitive and specialised requirements of aircraft, production needs to meet very particular standards of Form, Fit, Function and Qualification.

Solutions

For the first time ever, these parts are being manufactured in India at the ARDC CNC Shop. Indigenous design and manufacturing require state-of-the-art technical and technological capacity. This means that all relevant methodologies, procedures and strategies have to be built from the ground-up.

The goal of the program is to craft a naval version of the LCA Navy. India is one of very few countries that has the capability of designing, developing and manufacturing a fighter jet that is operational from an aircraft carrier. The prototype Tejas made news when it successfully conducted an ‘arrested landing’ – a procedure wherein the aircraft utilised a hook affixed to its underbody.

The project has ushered in the need to upgrade the manufacturing landscape, but with an emphasis on utilising the existing infrastructure to guarantee cost-effectiveness. The project is running under the directives furnished by HAL and sanctioned by the Design, Quality Assurance Department and RCMA.

In order to ensure design and development accuracy, every part of the process right from design to material selection is monitored rigorously. Sourcing is documented with product batch details and supplier information to guarantee a chain of accountability in the unfortunate event of a system failure. Raw material is thoroughly inspected for flaws, identification information, mechanical properties, dimensional checks, potential for interchangeability and supplier details and all documents are verified and a Certificate of Conformity granted. Every activity is recorded, right from the inspections and completed works reports to deviations, concessions and part disposition for rejected items.

Outcomes

R&D programmes are often evaluated in terms of the incremental R&D value the project offers or the degree of innovation or potential transformation it affords the field. The project has set an exacting standard for manufacturing that allows no compromises in quality, care or precision. The process is replicable and the methodologies can be utilised repeatedly for the same precise results.

The system is very cost-effective and in fact saves the manufacturer Rs. 31,456.32 per part. The new jig and fixture has removed the need for manual drilling and so the human factor expenditure eliminated results in a saving of Rs.5,20,320. The CNC Shop ARDC lists a savings of Rs. 22.07 Lakh in its manufacturing of four arrester hook platforms. The constant angle machining strategy and reduced material thickness all contribute to a high-quality, lowered-cost result. These financials are quantifiable benefits of the indigenous programme but it is also worth noting the qualitative benefits of quality, satisfaction, local capacity, time-effectiveness and subsequent manufacturing opportunities.

Challenges

Some of the challenges faced in the manufacturing process include difficulties in holding and clamping parts with a thickness of 145mm, component orientation challenges while trying to match large, heavy pieces to the grain direction, warpage arising out of machining surfaces, cutter lengths affecting dimensions and other such technical difficulties like maintaining uniform thickness, unavailability of highly specialised tools and preventing material expansion as a result of the heat output.

Innovation

Innovative, advanced technology has been used to stay true to design and manufacture the arrester hook as envisioned. The CNC Machining programme was used with the CATIA V5 software. Pecked Drilling Multiaxis Program, horizontal boring and maintaining cross axis pitch are some examples of the technical prowess displayed by the project runners. The development of a specialised jig and fixture to meet the very specific demands of the project is also a testament to the dedication of the organisation in leaving no stone unturned in setting a high standard. The Coordinate Measuring Machine was used to confirm contour, profile, pitch and hole dimension.

Opportunities

The project promises scalability and replicability. Advancements of the AHS Platform will augment capacity-building for future projects. These methodologies, knowledge, techniques and procedures may be adapted to any aircraft manufacturing process in the future. Interfacing with the Indian Navy is one of the key potentials of this project. Future projects can be planned with prospective financial and other details in hand based on the learnings from this pilot programme.

Summary

Indigenous design and manufacturing of the arrester hook platform promises vast potential in business opportunities for Hindustan Aeronautics Limited on both a national and international level. The increased capacity is a source of great pride and opportunity for the country and the potential of these new technologies and systems capabilities can be leveraged to great effect in other pursuits as well.