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.
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.
