Photos: Planefinder
By a guest writer
Iron Bird as the name suggests is a testing facility wherein the entire aircraft is functionally replicated to meet the testing requirements. The iron girders support the entire Hydraulics System, the Flight Control System (FCS), the Undercarriage System, the Utility Systems Management System (USMS), wherein the positioning and routing of the LRUs and the tubing/lines etc. are almost exact to the aircraft. This bird cannot fly but it facilitates the aircraft to fly safe and sound. The iron bird test rig is designed to enable the ground testing of the LCA-FCS in open and closed loop modes and also with the pilot in the loop. The test facility contains the Iron Bird Rig and all the subsystems like Cockpit, Avionics Suite, the Outside Window Imagery, all the IFCS LRUs etc., which interface with the heart of the Tejas Flight Control System, the Digital Flight Control computer (DFCC). In addition, it contains the six degrees of simulation platform on Flight Dynamics Simulator which runs the aircraft model in real time and provides sensor inputs to DFCC as well as information for the cockpit display system. Hence it is the Onboard Flight Program (OFP) residing in the DFCC which is tested with all sorts of checks in place in the form of engineering assessment at first and then the pilot evaluation. The facility provides with the actual scenario the DFCC hardware and the software shall experience in the aircraft that makes it a ‘close to the aircraft’ test set up. Even the aircraft hardware/software IFCS snags are replicated/ recreated to debug and troubleshoot them efficiently and effectively. It is quite noteworthy that more than 7 dozens different versions of DFCC OFP software has been test and evaluated by Iron Bird team, which gives an idea of the efforts involved in the development program of this calibre and a gradual march towards achieving the perfection as far as the software of a fly-by-wire aircraft is concerned. It is a well acknowledged fact that ‘extensive testing of flight control system on the iron bird rig has contributed to flawless flights of Tejas’. That is the statement made by the top brass to all the VIP and VVIPs who visit the facility quite frequently.
Since this is the last platform before the DFCC is delivered for fitment on to the aircraft, the responsibility and the accountability of the team is so immense that the team embraces an over- cautious approach and puts on all the efforts in totality. The balance between doing justice to the software and stick to the tight schedules make them put their efforts almost 12 hours a day, six days a week. Sometimes even the Sundays are also not spared.
At present there are two Iron Bird test facilities existing to cater for the needs of Tejas Mk1 fighter and Tejas Trainer/Naval Variant. The work on Iron Bird I facility was started way back in early years of the last decade of 20th century. The rig refinements and the initial engineering software testing started in the mid of that decade and formal flight worthy software testing in the year 1997. The completely tested and evaluated software for the first prototype namely the OFP V4019 was delivered in the year 2000 which led to the first flight of Tejas TD1 in January 2001. The second test facility, the Iron Bird – II was established mainly for Tejas Trainer and Naval variant and was commissioned in 2007-08. The Tejas trainer software was tested on it which finally led to the successful first flight of Tejas trainer variant with DFCC OFP V8002 in November 2009. The DFCC with the OFP for Naval variant is expected to be delivered to aircraft by April 2011.
There were many stumbling blocks in this entire chronology of testing the DFCC OFP at Iron Bird test facility. It started with the sanctions, post Pokharan – II, which made the path tougher and darker and then it was Y2K havoc, which led to providing jobs to anybody who could operate a computer. These disturbances blew off many experts from within the Tejas program and especially those working on FCS and particularly at Iron Bird. The Iron Bird saw an Avalanche breakdown and was left with just a handful of inexperienced engineers. But that didn’t stop the ‘left out team’ to continue with it efforts as it was the zenith of the project. Dr. B Subba Reddy singlehandedly took the completion of Iron Bird testing as a challenge and with those handful HAL engineers and few scientists from ADA delivered the DFCC hardware and the software to the aircraft. The team used to put almost 16 hours a day to utilise the system as per the schedule, to analyse the mammoth data captures, to go through each and every plots and figures before clearing the tests and offering the results to the certifying agencies. There were many problem reports / snags generated in the process and finally the product came in the form of OFP V4019, declared almost bug free.
The team was so cautious in its approach that with a single failure at the end of the prescribed 50 hours of fault free testing at Iron Bird, the clock was reset to zero and the entire test was redone amounting to a total of almost 110 hours of fault free testing. This enormously boosted the pilot’s confidence and made them eager to take off the actual wings. Prior to this fault free tests the team of Tejas pilots have undergone rigorous closed loop failure testing covering all the possible IFCS, electrical and hydraulics failures and studying and responding to them. This exercise also made them aware of handling the situation for possible failures on aircraft as they were to fly for the first time an indigenous fighter plane with fly-by-wire technology. Such an exercise was possible only at Iron Bird and the team left no stone unturned to offer it in totality to the pilots.
And the first flight happened, the nation applauded it, but nobody hailed Iron Bird team. Dr. B Subba Reddy was transferred to other division for administrative reasons and the program suffered another setback as he was also the deputy director of National Control Law (CLAW) team of Tejas. Some temporary arrangements were done from HAL side to fill the void left by Dr. Reddy, but to no avail. However the core Iron Bird team with the support of ADA was strong enough to deliver the products (the software versions with updates) in time. The HAL saw the Iron Bird team as an unproductive group of people since they were not directly contributing to the production targets of HAL and the approach continues till today. ADA celebrated the milestones of Tejas project with its scientists and between these two approaches, the Iron Bird team was left out unacknowledged at every occasion. The question still remains unanswered: “Whose baby is this Iron Bird, anyway?”
With the project directors of Tejas raising their voices at various forums, the Iron Bird team was finally augmented with HAL manpower in the year 2007 and currently boasts of 18 engineers of various domains. The team is headed by one Mr Sanjay Sharma, who has been associated with Iron Bird testing from the early days. It was his initiative that Iron Bird team still remains capable and efficient despite various setbacks. He also guides a team of 7 highly skilled engineers deputed to National Control Law (CLAW) team of Tejas at NAL. A big section of HAL higher management still remains unaware of the facts, potential, pains and achievements of the team.
We may be happy with the participation of private industry in the field of aeronautics, but the crude fact is that whenever an aerospace company or a venture has been established, it has eaten away the cream of the industries like HAL, ADA, and ADE etc. There are many who have been offered plum positions and fat salaries for similar work in these private establishments. And believe it or not, some of the delay in the Tejas project can be attributed to this very fact also. People of the level of project director, AGM etc. had redefined their loyalties and jumped to a world of leisure and comfort. In spite of these alluring offerings to the core people associated with the Tejas program the program had continued without much deceleration and the ‘Tejas Loyals’ came out with flying colours. Most of these crazy people have even never seen their salary slips from past many years. Ask them their basic pay even today and they will start looking at the skies, not for a clue but to tell the world, Tejas is our actual pay that we have earned. The soldiers at the borders have the obsession of dying for the country, we, at Iron Bird live with that and are always ready to die with that furore.
(The writer is a senior official with India’s Tejas program. No editing is being done to this copy by the blogger. The views expressed through this piece are purely that of the contributor and need not be necessarily the same as the blogger.)