High Speed Low Drag Bomb

The High Speed Low Drag (HSLD) bomb is a family of new generation short range air-dropped precision-guided munition that is currently being developed by India's Defence Research and Development Organisation (DRDO). This general-purpose bomb is made for the Indian Air Force (IAF) and can be used against the destruction of strategic high value enemy infrastructure.[3]

High Speed Low Drag Bomb
Type	Precision-guided general-purpose bomb
Place of origin	India
Service history
Used by	Indian Air Force
Production history
Designed	2017–present
Manufacturer	Armament Research and Development Establishment Ordnance Factory Board
Specifications
Mass	250 kg (550 lb) 450 kg (990 lb) 500 kg (1,100 lb) (additional RTU/BTU: ± 25 kg)[1][2]
Length	237 cm (93 in) 280 cm (110 in)
Warhead	Dentex Torpex 4B + RDX
Warhead weight	110 kg ± 5 kg 170 kg ± 5 kg
Detonation mechanism	Time fuze with electric/mechanical delay
Operational range	30 km from 10 km altitude 21 km from 5 km altitude 13.5 km from 2 km altitude
Flight altitude	10 km to 150 m
Guidance system	Mid-course: Fibre-optic gyro inertial navigation system with GPS/NavIC satellite guidance Terminal: Semi-active laser homing
Accuracy	<30 m to <3 m CEP
Launch platform	Dassault Mirage 2000 Mikoyan MiG-29 SEPECAT Jaguar Sukhoi Su-30MKI HAL Tejas

Between May to June 2017, multiple test were conducted successfully for 450 kg and 500 kg class general purpose bomb (GPB) as well as of precision guided high speed low drag (PGHSLD) munition.[4][5]

Description

The Armament Research and Development Establishment (ARDE), Pune is the primary agency that started developing HSLD with the help from other DRDO laboratories to upgrade the conventional free fall unguided ordnance used by the Indian Air force (IAF) fighter pilots while Ordnance Factory Board (OFB) is the lead production agency. The development started with the aim to replace the older generation imported general purpose bombs that impose huge drag loss on fighter aircraft used by the IAF. The HSLD bomb is specially designed to productively use the higher speed of up to Mach 1.1 and wider flight envelop of newer generation NATO and Russian origin as well as Indian made aircraft. High Energy Materials Research Laboratory (HEMRL) developed the conventional type warhead that features blast, fragmentation and shaped charge for bunker buster role which uses Dentex as primary explosive for HSLD 450 and Torpex-4B mixed with RDX that act as explosive booster for HSLD 500.[6] The warhead can be used to effectively destroy runway, railway track, bridge, industrial facility, dock and bunker. The family of HSLD comes in two versions namely a general purpose bomb (GPB) and a precision guided high speed low drag (PGHSLD) unit under three different weight class category which features semi-active laser homing and anti-jamming satellite navigation antenna. HSLD is designed to carry a nose extension unit (NEU) with fixed canard for lift, stability and two different types of smart tail unit (STU) with individual independent fins controlled by a flight control unit (FCU) attached to a telemetry module to cover the whole spectrum of mission profile. The STU features a retarder tail unit (RTU) that is for low-level bombing missions while a ballistic tail unit (BTU) that can used for strategic high level bombing.[7][8][9][10]

HSLD can be launched from variety of aircraft that are under IAF inventory like Dassault Mirage 2000, Mikoyan MiG-29, SEPECAT Jaguar, Sukhoi Su-30MKI and HAL Tejas. IAF has already successfully tested PGHSLD 500 from Su-30MKI platform.[11]

Trials

From 22 May 2017, ARDE and IAF conducted a series of carriage as well as carriage release trials (CRT) for High Speed Low Drag 500 kg class unit, with both general purpose and precision guided variant at Pokhran range, Rajasthan. In initial carriage trial, the bomb carried sensors, telemetry and data logger while during the separate CRT session, satellite guidance units were added which flew on Su-30MKI from Jodhpur Air force Station. The bomb touched the carriage limit of 1041 km/h (0.85 mach) at 150 metre altitude on Su-30MKI that performed a 6.5 g full roll manoeuvre during the first GPB 500 trial while the PGHSLD 500 separation was carried out from an altitude of 5 km at a speed of 900 km/h (0.73 mach). Both bombs cleared the flight envelop and completed all the required parameters without any form of mechanical damage during the high speed release from the aircraft. The trials were conducted with the help of Hindustan Aeronautics Limited (HAL), Indian Air Force Test Pilot School and Centre for Military Airworthiness and Certification (CEMILAC).[12]

Variants

• General Purpose Bomb – 250 kg, 450 kg and 500 kg
• Precision Guided High Speed Low Drag – 450 kg and 500 kg

Operators

 India

• Indian Air Force

References

1. OFB. "BOMB 250 KG HSLD (HE)". Ordnance Factories Board. Retrieved 23 March 2020.
2. OFB. "BOMB 450 KG HSLD HE". Ordnance Factories Board. Retrieved 23 March 2020.
3. Christopher, S (2017). DRDO Newsletter. Delhi: Defence Scientific Information and Documentation Centre. p. 5.
4. "2017: A year when India's Defence Research and Development Organisation, armed forces gained more strength". The New Indian Express. Retrieved 23 March 2020.
5. "The Indian Air Force in 2017 | ADU". www.aviation-defence-universe.com. Retrieved 23 March 2020.
6. Vadhe, Pawar, Sinha (3 October 2007). "Cast aluminized explosives (review)". Springer. 44 (July 2008): 461–477. doi:10.1007/s10573-008-0073-2.CS1 maint: multiple names: authors list (link)
7. Thiagarajan, Sriram (9 October 2017). "New Generation ARDE Munitions Boost Indian Airforce Firepower". Delhi Defence Review. Retrieved 22 March 2020.
8. DRDO. "GPS / INS Guidance and Control Kit for 450 kg HSLD Bomb". Defence Research and Development Organisation. Retrieved 23 March 2020.
9. DRDO. "ARDE CARRIES OUT SUCCESSFUL FLIGHT TRIALS OF 500 KG GENERAL PURPOSE BOMB". DRDO Technology Development Fund. Retrieved 24 March 2020.
10. DRDO. "ARDE CONDUCTS SUCCESSFUL TRIALS OF WEAPON PRECISION GUIDED HIGH SPEED LOW DRAG AIRCRAFT BOMB". DRDO Technology Development Fund. Retrieved 24 March 2020.
11. "DRDO Tests 500 Kg General Purpose Bomb From Su-30MKI Aircraft". www.defenseworld.net. Retrieved 23 March 2020.
12. "India successfully tests 500 kg Indigenous HSLD Bomb". East Coast Daily English. Retrieved 23 March 2020.

Footnotes

1. ^ DRDO tested ATGM NAG successfully. DRDO Newsletter. August 2017 Issue.

External links

• "DRDO Newsletter" (PDF). Defence Scientific Information and Documentation Centre. August 2017.