From LCA Tejas Mk.1 to LCA-AF Mk.2 to MWF to AMCA to TED-BF; From NLCA To MRCBF To TED-BF

Two Technology Demonstrators, five Prototype Vehicles and seven LSP-series aircraft (total of 14 aircraft) were built for the Bengaluru-based Aeronautical Development Agency (ADA) by Hindustan Aeronautics Ltd (HAL) for flight-testing and airworthiness certification taskings between 1997 and 2013. The IOC-1 period lasted 10 years, while the IOC-2 period lasted two years and the FOC period lasted six years—all in all 18 years.

In contrast, on June 26, 1974, Mikoyan OKB was selected to develop the MiG-29 M-MRCA and the first of 14 prototypes to be built made its maiden flight on October 6, 1977. It entered service in August 1983. The MiG-29K variant has an empty weight of 11 tonnes, 5.5-tonne weapons-load, and MTOW of 24.5 tonnes.

In late 1978 Dassault Aviation was contracted for development of Project ACT-92 (Avion de Combat Tactique). In October 1982, Dassault Aviation was contracted for building a technology demonstrator named Avion de Combat expérimental (Experimental Combat Airplane), or ACX. Construction of the 9.5-tonne demonstrator (Rafale-A) commenced in March 1984, was rolled out in December 1985 and made its maiden flight on July 4, 1986. After 865 flights with four pilots, the Rafale-A was retired in January 1994. On April 21, 1988, Dassault Aviation was contracted for building four Rafale prototypes: one single-seat Rafale-C, two carrier-based Rafale-Ms and one tandem-seat Rafale-B. The Rafale-C flew on May 19, 1991 while the Rafale-B flew on April 30, 1993. The first Rafale-M flew on December 12, 1991, followed by the second on November 8, 1993. The first production-series Rafale-M flew on July 7, 1999, while in December 2004, the French Air Force received its first three F2-standard Rafale-Bs. The Rafale-C has an empty weight of 9.85 tonnes, internal fuel capacity of 4.7 tonnes, 9.5-tonne weapons-load and MTOW of 24.5 tonnes.

TD-1 (KH-2001) first flew on January 4, 2001; followed by TD-2 (KH-2002) on June 6, 2002. This was followed by the PV-1 (KH-2003) flying on November 25, 2003; PV-2 (KH-2004) on December 1, 2005; PV-3 (KH-2005) on December 1, 2006; PV-4 (KHT-2009) on November 26, 2009; and PV-5 (KHT-2010) on November 8, 2014. These were followed by seven LSP-series LCAs, comprising LSP-1 (KH-2011) that took to the skies on April 25, 2007 and was powered by GE Aero Engines-supplied F404-F2J3 turbofan; LSP-2 (KH-2012) first flying on June 16, 2008 and being the first to be powered by F404-IN20 turbofan; LSP-3 (KH-2013) flying on April 23, 2010; LSP-4 (KH-2014) on June 2, 2010; SP-5 (KH-2015) fitted with NVG-compatible cockpit lighting and autopilot on November 19, 2010; LSP-7 (KH-2017) on March 9, 2012 with a reshaped APU air-intake; and LSP-8 (KH-2018) in March 2013.

Between October 1985 and 2003, the IAF had accorded permanent waivers to 22 of the requirements listed out in its ASQR.

October 25, 2007: Tejas Mk.1 PV-1 test-fired a R-73E SRAAM in a ballistic non-guided) mode off Goa.

December 11, 2007: Tejas Mk.1 PV-2 flew with Litening-2 LDP.

October 2009: Tejas Mk.1 PV-3 and LSP-2 completed air-to-surface weapons delivery trials.

April 23, 2010: LSP-3 flew with a hybrid version of the Elta EL/M-2032 multi-mode radar, a homegrown IFF transponder and homegrown chaff/flare dispensers.

November 30, 2010: Tejas LSP-4 fired a R-73E SRAAM guided by the Targo HMDS off Goa.

January 10, 2011: Tejas Mk.1 was accorded the Initial Operational Clearance-1 (IOC-1) Release to Service Certificate by the Centre for Military Airworthiness and Certification (CEMILAC) after 32 performance parameters were waived by the IAF.

December 20, 2013: Tejas Mk.1 was accorded the IOC-2 Release to Service Certificate after logging 2,587 sorties covering over 1,750 hours with 13 prototypes flown by 17 test pilots of the IAF and Indian Navy. There were then 53 significant shortfalls in the L-MRCA’s developmental effort. However, the post-IOC-2 service induction process at Sulur air base began only on January 17, 2015.

October 1, 2014: Tejas Mk.1 SP-1’s maiden flight took place.

January 12, 2015: Tejas Mk.1 PV-1 flew with an internally-mounted integrated EW suite (UEWS) developed by the Defence Avionics Research Establishment (DARE).

January 17, 2015: SP-1 officially handed over to the IAF. HAL delivered one SP-series in 2015-16; two in 2016-17; five in 2017-18 aircraft and eight in 2018-19. The SP-1 first flew on October 1, 2014; SP-2 on March 22, 2016; SP-3 on September 28, 2016; SP-4 on March 3, 2017; SP-6 on June 30, 2017; SP-5 on February 8, 2018; SP-8 on March 13, 2018; SP-9 on March 24, 2018; SP-10 on July 27, 2018; SP-11 on October 10, 2018; SP-12 on November 28, 2018; SP-13 on January 30, 2019; SP-14 on January 20, 2019; SP-15 on March 22, 2019; and SP-16 on March 12, 2019. SP-17 to SP-20 and SP-37 to SP-40 will be tandem-seaters. Each SP-series Tejas Mk.1 undergoes three test-flights undertaken by HAL’s Test Pilots followed by another three by the IAF’s pilots. Build-standard of eight FOC-compliant tandem-seat operational conversion trainers was readied by April 2019. The first such aircraft will make its maiden flight in late 2021. The confirmed orders now stand at 32 Tejas Mk.1 single-seaters fighters (16 IOC-compliant and 16 FOC-compliant) and eight FOC-compliant tandem-seaters.

August 2015: UK-based Cobham handed over newly-designed quartz radome and bolt-on in-flight refuelling (IFR) probe to HAL for installation on Tejas Mk.1 LSP-8 (KH-2018). Cobham was awarded the contract in 2014, but it missed three successive delivery timelines (October 2014, end of January 2015 and April 2015) for both items. Had Cobham adhered to its delivery timelines, it would have been possible to wrap up ground check-outs for the IFR probe in October-November 2014 and then commence flight-trials. 25 day/night flights at different altitudes and speeds are needed to clear the IFR system and had the probe been delivered in September 2014, it would have easily been cleared for certification before mid-2015.

February 5, 2016: Tejas Mk.1 LSP-7 test-fired a Derby BVRAAM in a ballistic non-guided) mode in Jamnagar.

November 7, 2016: India’s Defence Ministry approved a plan for procuring 83 Tejas Mk.1As worth ₹50,025 crore under the Acceptance of Necessity (AoN) scheme.

January 31, 2017: Tejas LSP-8 (KH-2018) made its first flight fitted with a Cobham in-flight refuelling probe.

May 16, 2017: Tejas Mk.1 LSP-7 fired a Derby BVRAAM in guided ‘lock-on after launch’ mode at Chandipur. In addition, ADA equipped the LSP-2 platform with a LRDE-developed ‘Uttam’ AESA-MMR developmental prototype along with an integrated liquid cooling system.

October 2017: The provisional DAL (Drawing Applicability List) for FOC-compliant Tejas Mk.1 SP-series was released, followed by the amended one in August 2018. (DAL is the standard of preparation for production). In addition, the LCA-AF Mk.2’s design was modified to have a 1-metre fuselage plug-in module, all-up weight of 16.5 tonnes, a payload of 5.5 tonnes and 3,300kg internal fuel capacity.

December 20, 2017: The IAF issued a single-vendor tender to HAL for procuring 83 Tejas Mk.1As (73 single-seaters and 10 tandem-seaters) for equipping four IAF squadrons and HAL submitted its first technical and commercial response to it in March 2018. HAL quoted Rs.463 crore (US$64.5 million) for Tejas Mk.1A versus Rs.363 crore ($50.6 million) for the Tejas Mk.1.

February 27, 2018: Hot refuelling-cum-sortie was conducted by Tejas LSP-8.
April 27, 2018: Tejas Mk.1 LSP-7 fired a Derby BVRAAM in guided ‘lock-on after launch’ mode against a manoeuvrable unmanned aerial target-drone at Chandipur.

September 10, 2018: LSP-8 was successfully refuelled mid-air by an IAF IL-78MKI. LSP-8 took-off from Gwalior air base, before meeting up with an Il-78MKI operating from Agra air base. LSP-8 used a Cobham-supplied refuelling probe to connect with the IL-78MKI’s Cobham-supplied hose-and-drogue system for a series of dry contacts on September 4 and 6, before a first transfer 1,900kg of fuel took place when the LSP-8 was cruising at 270 Knots.

October 2018: The LCA-AF Mk.2 morphed into the Medium-Weight Fighter (MWF), whose fuselage would be 1.35 metres longer, will carry 6.5 tonnes of payload and 3,300kg of internal fuel. 

December 2019: LSP-7 successfully demonstrated dropping of OFB-built 250kg/450kg HSLD bombs, OFB-built Mk.11N retarder bomb, FAB-250 bomb, OFAB-100-120 bomb. Operating out of IAF air bases like Jamnagar, Jaisalmer, Uttarlai, Gwalior, Goa, Leh, Pathankot, the LSP-7 demonstrated weaponised platform readiness for ORP scramble missions and three-sortie/day turnaround service in all weather conditions and at different operating altitudes.

February 20, 2019: FOC certificate and Release to Service Document released after 10 performance parameters were waived by the IAF. These included the non-installation of the twin-barrelled Gryazev-Shipunov GSh-23 cannon.

March 11, 2019: Tejas Mk.1 SP-16 first flew for the first time, followed by SP-15 on March 22. SP-16 was the first of the SP-series to be using wings made by Larsen & Toubro (L & T) in January, and wiring harnesses and pipings supplied by HAL’s Prayagraj-based subsidiary Naini Aerospace Ltd (previously a sick industrial unit of Hindustan cables Ltd) on March 27, 2018.

September 2019: Revised price-quote by HAL after renegotiations stands at Rs.417 crore ($58.1 million) per Tejas Mk.1A in flyaway condition minus its weapons systems. In comparison, the HAL Nashik-built Su-30MKI costs Rs.415 crore ($57.8 million) per unit.

October 2019: SP-21, the first FOC-compliant Tejas Mk.1, began being assembled and will contain an IFR probe, pressure-refuelling with three drop-tank configuration, integration of 725-litre and 450-litre drop-tanks, improved wing navigation lamps, in-flight windmill relight, dual-ejector rack for SRAAMs, and zoom-climb flight mode. The Teajas Mk.1A too will not have the twin-barrelled Gryazev-Shipunov GSh-23 cannon on-board. Instead, an as-yet unselected pod-mounted 30mm cannon has been specified.

The MWF, whose maiden flight as per ADA’s claims will be in 2024 (following a rollout in 2022), will be built to LSP standards in Initial Operational Clearance (IOC) configuration. A total of four LSP-series MWFs are planned for construction and these will be subjected to a total of 2,000 hours of certification-related flight-tests. Series-production of 201 MWFs for equipping 12 IAF squadrons will begin in 2028 as per ADA’s prediction, and each MWF will have an empty weight of 7.7 tonnes, weapons-load of 6.5 tonnes, internal fuel capacity of 3.3 tonnes and MTOW of 17.5 tonnes. Powerplant will be a single 98kN-thrust F414-GE-INS6 turbofan.

The AMCA project was conceptualised in 2006 and between 2008 and 2014, five conceptual wind-tunnel scale-models were tested. In April 2010 the IAF had finalised the AMCA’s ASQRs. In October 2010, a sum of Rs.100 crore was released to ADA for preparing feasibility studies in 18 months. Feasibility Report was compiled and its review held in November 2013. The Feasibility Report was updated in October 2015. The conceptual phase began in 2015, while the detailed design phase began in February 2019. In April 2018, funding for building two AMCA technology demonstrators (whose maiden flight as per ADA’s claim is due for 2025) was released. The Engineering Technology & Manufacturing Development (ETMD) phase for producing four flying prototype aircraft has yet to begin. AMCA will have an empty weight of 16 tonnes, internal fuel load of 6.5 tonnes, internal weapons load of 1.5 tonnes, external weapons-load of 5 tonnes, and MTOW of 29 tonnes. Powerplant will be twin 98kN-thrust F414-GE-INS6 turbofans offering a total thrust of 180kN.

Since the Indian Navy requires only 57 TED-BFs for service-induction, this is too small a number for justifying the enormous developmental funds required. Neither is there any possibility of the IAF expressing its preference for a shore-based TED-BF variant by ditching the single-engined MWF option. Hence, ADA’s claim about the TED-BF making its maiden flight by 2026 and being ready for service-induction by 2031 tantamounts to an impossibility.

The maiden arrested recovery of the LCA Navy Mk.1/NP-2 technology demonstrator on board INS Vikramaditya on January 11, 2020 and its following maiden takeoff a day later marked the attainment of a crucial milestone in the Indian Navy’s (IN) developmental process for obtaining a homegrown carrier-based multi-role combat aircraft (MRCA) solution. It may be recalled that Phase-1 of full-scale engineering development (FSED-1) for the LCA (Navy) technology demonstration project was sanctioned in March 2003 by the Government of India with grant-in-aid seed funding of Rs.949 crore and a planned completion date of December 2009. The IN contributed 40% of the development cost, with the rest being put up by the Defence Research & Development Organisation (DRDO), which controls the Aeronautical Development Agency (ADA)—designer and developer of the LCA family of L-MRCAs. The objective then was to develop a naval carrier-borne MRCA capable of Ski-Jump Takeoff with Arrested Recovery for landing (STOBAR concept). It was initially envisaged that converting the already flying Tejas Mk.1 to a naval aircraft would take about six to seven years, with structural changes restricted to about 15%. The two naval prototypes sanctioned were to be used primarily to demonstrate Carrier Compatibility and also to demonstrate Initial Operational Capability with air-defence configuration. However, contrary to initial assumptions, during the aircraft design and development phase, it turned out to be significantly different from the time of sanction in 2003 and challenges increased progressively. Further, the major constraint of design space due to the existing Tejas platform resulted in a sub-optimal design and compromises leading to the LCA Navy Mk-1 variant (NP-1) being heavier than anticipated. Consequently, Navy LCA (NLCA) Mk2 design powered by a higher-thrust turbofan was taken up in the FSED-II stage of the project, which was sanctioned in December 2009. However, by 2014, the IN realised that even the NLCA Mk.2 would have shortfalls in the full-mission capabilities.

This realisation had dawned after the IN had done a comprehensive assessment of flight operations with its twin-engined MiG-29Ks from the STOBAR flight-deck of INS Vikramaditya. To fully understand the assessment, one must first understand what distinguishes land-based flight operations from carrier-based flight-operations, plus the difference between STOBAR and CATOBAR flight-deck designs. Usually, there are three parameters relating to the takeoff of any type of shore-based aircraft: 1) thrust-weight ratio, 2) rolling distance, 3) the minimum liftoff safety speed. When an aircraft attains a certain rolling distance (usually much longer than the length of an aircraft carrier’s deck) at an acceleration produced by its thrust-weight ratio for takeoff, it reaches the minimum lift-off safety speed. Upon reaching this, the lift force of the aircraft is equal to the weight of the aircraft, and then the aircraft lifts off. So the lift force of an aircraft is proportional to the square of its speed. If the aircraft slides at acceleration for a distance which is shorter than the runway length when it takes off and fails to reach the minimum safety lift-off speed, the lift force produced by the aircraft’s wings will be less than the weight of the aircraft, so it cannot lift off. The landing, on the other hand, is accomplished in five stages: (1) glide; (2) flatten (when the wheel is 2 metres above the ground, throttle back to the idle speed, reduce the glide angle, and exit glide state at the height of 0.5 metres); (3) level flight at a deceleration (minimum level flight speed); (4) fall to touch down (at this moment, the aircraft’s speed is decreased to an extent that the lift force is no longer enough to balance the aircraft’s weight); (5) roll to land (under the action of wheel friction and air resistance etc, rolling at a deceleration until it halls).

When it comes to carrier-based aviation, due to the limited length of the flight deck of the aircraft carrier, there are mainly three take-off options for carrier-based aircraft: vertical takeoff (namely the vertical/short-range rolling takeoff), ski-jump take-off (or called sliding-tilted takeoff), and ejection takeoff (such as steam ejection takeoff, electromagnetic rail-launch ejection takeoff). For ski-jump takeoff, the aircraft first rolls at acceleration on the runway of the flight deck of an aircraft carrier only depending on its own power, then it leaps into the air through the upswept deck on the front part of the aircraft carrier, and then takes off. The principle is that the upswept angle of the deck (14 degrees) is regarded as the ejection angle, although the aircraft has not yet reached the takeoff speed when it rolls and leaves the aircraft carrier. The landing on an aircraft carrier is achieved by gliding to directly hook the arresting cable on the aircraft carrier (without the above stages of level flight at a deceleration, etc). A total of 3 or 4 arresting cables are installed on the canted deck of the aircraft carrier, in which the first one is arranged apart from the aft by 60 metres, and the remaining ones are arranged at an interval of 6 metres or 14 metres. The height of the arresting cable is 50 centimetres above the deck surface. The aircraft glides from upper right of the stern of the aircraft carrier, which is travelling rapidly, hooks the arresting cable with the tailhook, and then rolls on the deck within 100 metres to brake. The statistics show that 80% of aircraft accidents on board aircraft carriers occur in the course of touching down on to the top-deck but not in the air. The factors attributing to a complicated, difficult and risky landing process for the aircraft include: 1) short on-deck runway; aircraft carrier is limited in length, and the section for the carrier aircraft to land is more limited, while the length of landing area on the aircraft carrier is relevant to the safety in landing of the carrier-borne MRCA; 2) high landing speed; in the existing technology, when directly gliding to touch down onto the flight-deck, the MRCA does not throttle back to decelerate, but requires an appropriate force, so that it can immediately undertake a Bolter in case the tailhook misses all the arresting cables; 3) the accuracy requirement for pre-determined landing point is strict; for the accuracy of the landing point, none of longitudinal, lateral and height errors can be large, otherwise the MRCA may not hook the arresting cable, or may land on the aft or on the right side of the flight-deck, while the MRCA needs to, during gliding at high speed, finish hitting the landing position on the moving flight-deck; 4) control of the gliding angle (between 3.5% and 4%); 5) alignment with the centreline of the runway, because an alignment is more important than the gliding angle. Since the runway of the aircraft carrier is very narrow, if the aircraft deviates to the right, it may hit the superstructure (island) of the aircraft carrier, and if the aircraft deviates to the left, it may hit other aircraft on the parking apron. So during the landing stage, the MRCA should fly (glide) in a vertical plane where the centreline of the runway is located. However, the centreline of the canted deck-runway used for landing is not consistent with the heading direction of aircraft carriers, and presents an angle of between 6 degrees and 13 degrees (namely the canted deck and the longitudinal axis of the aircraft carrier form an angle of 6 degrees and 13 degrees). Such a design aims to allow the MRCA to roll after landing so as to avoid other deck-based MRCAs that are awaiting takeoff at the front portion of the flight-deck.

When a carrier-based MRCA takes off from a curved STOBAR deck it suddenly jumps into free air. The objective is to approximately reach the suitable speed and AoA at the end of the ski-jump, without exactly respecting the MRCA’s lift-to-weight equilibrium. It may well be in an infra-lift condition, but the overall strategy aims at keeping the longitudinal acceleration by maintaining engine thrust, and giving full control to the pilot who, until this moment has hardly intervened in the manoeuvre. An acceptable aircraft-vessel compatibility matching implies that the flight speed will reach a minimum value to sustain level flight before the aircraft altitude over the sea crosses below a certain safety threshold. The thrust-to-weight ratio at take-off must thus be appropriately matched to the available deck length and the ski-jump geometry, including wind-on-deck effects. The approach speed must be compatible with wind-on-deck and the available landing distance to completely stop the MRCA after engaging the last arrestor-cable. And lastly, the thrust-to-weight ratio at approach must be high enough as to allow fast acceleration and safe liftoff (Bolter) should the aircraft hook failing engaging the arresting pendants.

A twin-engined naval MRCA operating from a STOBAR flight-deck can at best only take off with half-load (of either fuel or weapons payload), and the engine is in the state of thrust augmentation at the time of takeoff, thus shortening the aircraft’s service-life. The MRCA is also required to be added with some structural weights, such as increasing the wing area, just in order to improve the lift force for realising the ski-jump takeoff. The takeoff weight and takeoff efficiency of takeoffs from STOBAR flight-decks are thus less than that of the ejection takeoff, and the combat efficiency is thus poorer than that of the MRCA taking off from a CATOBAR flight-deck. The STOBAR flight-deck design thus limits MRCA takeoff weight and shifts the full burden of takeoff propulsion onto the aircraft, thus increasing the amount of fuel consumed at that stage. This in turn restricts the fuel and weapons payload that the MRCA can carry, thereby reducing its range, loitering time, and strike capabilities. STOBAR is also more affected by wind, tide, rolling, and pitching. Furthermore, it needs more flight-deck space for takeoff and landing, thus limiting the parking space and having an adverse effect on takeoff frequency–based crisis reaction. For instance, on all existing STOBAR aircraft carriers (Project 11430 INS Vikramaditya, Project 1143.5 Kuznetsov and the two PLA Navy vessels CV-16 Liaoning and CV-17 Shandong) there are two types of runway lengths—the shorter 115-metre one in a right-to-left orientation for launching MRCAs with greatly reduced weapons/fuel loads; and the longer 180-metre one in left-to-right orientation for launching MRCAs with greater but not maximum weapons/fuel loads.

In comparison, the CATOBAR design, which is mostly associated with large carriers, minimises aircraft fuel consumption on takeoff, thus enabling better payload, range, loitering time, and strike capability. Its runway requirement is also minimal, thus allowing more flight-deck parking and faster launches, even simultaneous launch and recovery, resulting in quicker crisis response. Lastly, unlike STOBAR flight-decks, CATOBAR flight-decks can also launch heavier fixed-wing AEW and ASW aircraft.

NLCA Developmental Milestones

The LCA (Navy) programme has involved development of the NP-1 tandem-seat operational conversion trainer and NP-2 single-seat multi-role combat aircraft, one structural test specimen for fatigue-testing, creation of Navy-specific flight-test facilities in Bengaluru and Goa, construction of a shore-based flight-test facility or SBTF at INS Hansa in Goa (for enabling arrested landing recovery, plus takeoff from a half-metal half-concrete 14-degree ski ramp and a flight deck ranging from 195 metres to 204 metres in length, and validating the simulation model for flight performance within ship-motion limits, validating the flight controls’ strategy with all-up weight and asymmetric loading, validating the load analysis methodology), and flight-tests/flight certification for aircraft carrier-based flight operations. The SBTF also has its integral flight-test centre equipped with line-of-sight telemetry/high-speed three-axis photogrammetric systems, systems for validating thrust measurement algorithms, systems for measuring wind-flow patterns, INS/DGPS-based trajectory measurement systems, RGS integration facility, plus a workshop.

To date, the LCA Navy Mk.1 has demonstrated the following IN-specific technologies while operating from the SBTF: supersonic flight; takeoffs from the Ski-Jump was successfully demonstrated, including 12 Ski-Jumps when armed with R-73E SRAAMs missiles, plus night-time Ski Jumps; hot-refuelling; flying of 3-hour duration achieved in one sortie; in-flight jettisoning; Integration of AHS with the NP-2 airframe; and the development of a weight-optimised telescopic landing gear for high sink-rate landing with the help of consultancy from Airbus Military. In addition, a naval standard Structural Test Specimen (STS) has been built and integrated with the Main Airframe Structural Test (MAST) rig to test horizontal and vertical loads during a deck recovery, including 7.1 metre/ssecond sink rate and a 45-tonne load on an arrester wire. Compared to the Tejas Mk1, the LCA (Navy) Mk1/NP-2 is a technology demonstrator that features a drooped nose section, strengthened airframe structure, twin leading-edge vortex control surfaces or LEVCONS (for attaining lower approach speeds), main landing gear with higher sink-rate, increased internal fuel capacity, a Navy-specific avionics suite (including the locally developed autopilot and auto-throttle) and weapons package, and an arrester hook. The NP-2 is now being subjected to a carrier-based flight-test regime on board INS Vikramaditya, where seaborne wind conditions winds-on-deck envelopes (especially ship motion, cross-winds and high wind-on-deck speeds) are far more favourable than those around the SBTF. Integration with carrier-based support and weaponisation facilities, plus jettisioning of ventral stores, thrust data validation, and attaining hands-free and non-disorienting takeoff with supplied HUD symbology formats and high AoA are being demonstrated and validated in this phase of flight-tests. Incidentally, since the IN is involved for the very first time in its history with developing a carrier-based MRCA, it is resigned to the possibility of the NP-2 technology demonstrator ‘breaking up’ while in the process of subjecting the aircrafts’ main landing gears to arrested recoveries at sea. It must be noted here that the undercarriages of carrier-based aircraft collapse or break-up is not due to compression, but due to suspension.

Of utmost importance during the Carrier Compatibility Trials (CCT) are the data-points to be obtained for validating the flight-control logic during the NP-2’s carrier-borne flight operations. This in turn will help in the optimisation of the flight-control logic by the National Control Law Team (that comprises talents from FMCD, ADA, CAIR, and HAL and operating from the premises of NAL’s Flight Mechanics & Control Division, or FMCD). Data-points pertaining to boundary-limiting, automatic low-speed recovery, carefree manoeuvring, autopilot functionality (that supports hands-free takeoff mode , altitude and flight path select & hold mode, as well as auto level off features with both horizontal and vertical navigation modes) will be the most crucial. In addition, the service-life of the Arrestor Hook System (AHS)—designed and built by HAL’s Aircraft Research & Design Centre (ARDC)—too will be determined during the ongoing CCT. After having verified in-air operation of the AHS in Bengaluru on July 23, 2018, NP-2 fitted with the AHS has been operating from INS Hansa Goa, since July 28, 2018.

Due to limited area in deck landing zone and the demand for bolting and go-around, carrier-based MRCAs usually land on deck via impact method under high sinking speed and high engaging speed along a fixed glide-path angle. The impact load, braking load of arresting cable, and other loads at the moment when the MRCA touches the flight-deck put forward higher requirements for design and analysis of landing gears and airframe structure, especially for the structures closely related to landing. Gas-oil leakage in the shock absorber of any carrier-based MRCA’s landing gear is a frequent and common failure, which can deteriorate the absorbing performance. Since shock absorber performance varies with different gas-oil ratio caused by gas-oil leakage, this will be another crucial area of data-point assessment. Since the NP-2’s nose landing gear is comprised of the shock strut, drag brace, launch bar and power unit, all these major structural elements will be subjected to gruelling usage in order to determine their maximum operating limits. Presently, the landing gear assemblies of all fourth-generation naval MRCAs are built from Aermet 100 high-strength non-stainless steel, which is known for its damage tolerance and resistance to crack growth. However, this alloy is highly susceptible to both corrosion and hydrogen embrittlement, which can lead to stress corrosion cracking (SSC). This sensitivity makes SSC the primary failure mechanism for landing gear—a failure that often causes significant collateral damage to the aircraft, even though the failure usually takes place while it is parked. As a result, a number of aircraft components, such as landing gears, require a costly cadmium coating process to protect against corrosion. Cadmium, a known carcinogen, represents significant environmental risks in both primary manufacture and at MRO facilities. Eliminating this coating process thus has a tremendous potential for reducing long-term maintenance costs and eliminating environmentally hazardous processes. The US Navy is now experimenting with Ferrium S53 steel that provides much greater resistance to general corrosion and to SCC; excellent resistance to fatigue and to corrosion fatigue; and high hardenability. Its resistance to general corrosion is similar to that of 440C stainless steel, but it has much greater fracture toughness.

Next, a US Navy Carrier Suitability Test Team will audit all the data-points obtained from the CCT and its experience in developing and maintaining carrier-borne MRCAs will be most useful, since the IN wants to replicate almost all those flight-safety-related features that are now finding their way on board all US Navy carrier-based MRCAs. One such feature is the US Navy’s latest Maritime Augmented Guidance with Integrated Controls for Carrier Approach and Recovery Precision Enabling Technologies (MAGIC CARPET), a software package that makes a carrier approach nearly as routine as a runway landing. The system works with the carrier-based aircraft’s autopilot to maintain the approach using ‘direct lift control’. In other words, once the pilot sets the glide angle of the approach, it becomes the ‘neutral’ setting for the controls. The autopilot then tracks the position of the flight-deck, adjusting the throttle, flaps, ailerons, and stabilisers to keep the flight path and AoA on point. Instead of maintaining continuous pressure on the stick and making myriad inputs before landing, the pilot can instead relax. Any adjustments he/she does make are incorporated into the autopilot settings. However, the system is not fully automated, and pilots remain in control. MAGIC CARPET just simplifies the descent. And because it augments existing flight-control systems, it does not require hardware modifications.  Pilots typically perform 300 corrections to their flight-path in the final 18 seconds of an approach. MAGIC CARPET drops that between 10 and 20. Beyond reducing stress, MAGIC CARPET also minimises the time and effort needed to train pilots for carrier deck landings, thereby allowing more time for tactical training. It also reduces the time and money spent on manoeuvring aircraft carriers into ideal landing positions. Lastly, the fewer aborted landings saves fuel, and fewer hard landings saves wear-and-tear on aircraft.

NLCA Timeline

July 6, 2010: The first NP-1 prototype is rolled out.

April 27 2012: NP-1 makes its maiden flight, nine years from the sanction of the programme.

2013: SBTF is built by Goa Shipyard Ltd along with the construction arm of DRDO CCER & D (W) Pune. Restraining Gear System (RGS) installation also successfully completed.

December 19, 2014: NP-1 takes off from the SBTF for the first time, piloted by the IN’s Chief Test Pilot Cmde Jaideep Maolankar of the National Flight Test Centre (NFTC). It was planned to have a minimum climb angle of 5.7 degrees for the first launch. However, there was an unexpected bonus in terms of excess performance and the actual minimum climb angle was in excess of 10 degrees. The AoA after ramp exit reached 21.6 degrees.

February 7, 2015: NP-2 prototype takes to the skies in Bengaluru, flown by Captain Shivnath Dahiya from the NFTC, who ensures that the 35-minute maiden sortie is smooth. NP-2 has been customised (plug & play) to incrementally accept modifications for landing aids like LEVCON Air Data Computer, Auto-Throttle, and internal/external AoA lights. NP-2 is the lead aircraft for AHS integration.

January 24, 2017: The IN releases a RFI for procurement of approximately 57 multi-role carrier-borne fighters (MRCBF) for its future aircraft carriers.

December 2, 2017: Then Chief of the Naval Staff Admiral Sunil Lanba states that the IN is scouting for another carrier operations-compatible MRCA besides the MiG-29K, since both the existing NLCA Mk.1 and the projected NLCA Mk.2 lack the payload required to be effective when operating from an aircraft carrier.

September 19, 2018: NP-1 takes off from the Ski-Jump and then makes an arrested landing at the SBTF in INS Hansa, Goa. The same day, NP-2 accomplishes the same feat.

October 19, 2019: At the Indian Defence & Aerospace Summit, Chief of the Naval Staff Admiral Karambir Singh reveals that the IN wants ADA to develop a Twin-Engine Deck-Based Fighter (TED-BF) with MTOW of 25 tonnes.