|Manufacturer:||Singapore Technologies Kinetics Ltd - STK|
|Product type:||Weapons & Weapon Systems|
Ordnance Development and Engineering of Singapore (ODE), a company of Chartered Industries of Singapore, developed a 155 mm gun-howitzer with a 39 calibre barrel known as the FH-88. Early in 2000 the company became part of Singapore Technologies Kinetics.
There were five prototypes produced over a period of four years beginning in 1983. These were followed by a preproduction batch of six 155 mm FH-88 gun-howitzers that incorporated a number of improvements as a result of trials with the prototype weapons.
First production FH-88s were completed in 1987, with the weapon becoming operational with the Singapore Army the following year.
It is believed that a total of 52 systems were built for the Singapore Army. These replaced Israeli older Soltam Systems 155 mm M71S (with the S standing for Singapore, as they have been modified) systems which have been placed in reserve. Indonesia took delivery of five 155 mm FH-88 systems in 1997. It is understood that these were brand new weapons.
The 155 mm/39 calibre FH-88 has been followed in production by the Singapore Technologies Kinetics 155 mm/52 calibre FH2000 which is covered in a separate entry.
The more recent FH-2000 artillery system uses some components of the FH-88 including the sighting system, APU and the complete family of 155 mm ammunition.
More recently Singapore Technologies Kinetics has developed the new 155 mm/39 calibre Pegasus Light Weight Howitzer (LWH) which is already in service with the Singapore Armed Forces (SAF).
The monobloc 155 mm barrel is 39 calibres long and is autofrettaged. A double-baffle muzzle brake is fitted. The breech is of the hinged, interrupted screw type and automatically opens during the latter half of the return stroke of the recoil movement. The camplate lifting mechanism incorporates a safety lock to prevent accidental closing of the breech screw and the firing mechanism cannot be activated if the breech screw is not fully closed. Obturation is achieved using a resilient pad. The firing mechanism is a mechanical 'trip action' type which is actuated either by pulling the lanyard or operating the firing handle at the layer's seat. Primer feeding and extraction is automatic using a 12-round magazine. A flick rammer is used with power derived from an independent power pack.
The hydropneumatic recoil mechanism is of the independent-type single-recoil system. The recoil mechanism, connected to the recoiling and static parts of the gun, consists of a recoil brake and a recuperator/counter-recoil mechanism. The governor rod in the recoil brake varies the orifice for hydraulic oil to flow throughout the recoiling stroke, absorbs and ensures minimum and uniform recoil on the carriage. The pressurised nitrogen gas in the recuperator/counter-recoil mechanism is to return the barrel after recoil and also holds the barrel in its fully run-out position at all elevations.
There are two independent pneumatic equilibrators that balance the weight of the elevated mass throughout the full range of elevation. The equilibrator is made up of a cylinder, piston rod and a receiver using nitrogen gas as the working medium.
The cradle, which is made of high-strength alloy steel, supports and guides the recoiling parts. It houses the recoil mechanism and provides attachments for the equilibrators, camplate arm, elevating arc, flick rammer and the sighting system.
The saddle, which is made of high-strength alloy steel, comprises two side frames welded to a circular baseplate. It supports the elevating mass through the trunnion bearings and houses the elevating and traversing mechanism. It also provides attachments for the equilibrators and sighting equipment.
The elevating mechanism, with the aid of the equilibrators, enables the 155 mm/39 calibre ordnance to be elevated or depressed with accuracy and ease. The traversing mechanism, mounted in front of the saddle, enables the ordnance to be swivelled horizontally.
The flick rammer is an electronically controlled hydraulic system, which in turn operates the mechanical system. The latter basically consists of the swivel arm and the ramming unit. The swivel arm, with the loading tray attached, is pivoted at the rear end of the cradle.
The chassis serves as the base frame to join the upper carriage to the lower carriage. During firing it transmits all of the load on the upper carriage to the ground through the firing platform and trail legs.
The chassis is a welded structure of high-strength steel on a box section design, with provision for the mounting of the main bearing, rocker beams, firing platform, trail legs and the APU. The firing platform is connected to the chassis assembly through the pad arrangements and lifts the weapon off the ground for firing. It is operated by a telescopic cylinder, which is completely isolated from all firing loads when the platform is fully deployed. An indicator is incorporated to show when the platform is fully deployed.
The trails are made of high-strength steel and, together with the firing platform, serve as the main support for the weapon. In the closed position they serve as a base for locking the barrel in a fixed position for travelling. Hydraulically powered operations permit the trails to be spread or closed within 10 seconds.
The two trail wheels, attached to the trail ends, can be steered, raised or lowered by hydraulically powered operations controlled by the driver.
The spades, an integral part of the trails, transmit the firing loads to the ground. As the spades are permanently hinged at the end of the trails, no carrying and mounting of spades is required during deployment.
The carriage is of the split trail type and is fitted with an APU. The 155 mm FH-88 can be towed at speeds up to 80 km/h and is self-propelled at speeds up to 16 km/h. The APU is a 96 hp Deutz air-cooled turbocharged diesel which powers a hydrostatic drive system on the front wheels. Back-up systems include a battery-operated pump and a manual pump. The APU can be operated in tandem with the towing vehicle for maximum traction and can be remote controlled. The APU has a 50 litre fuel tank providing an operating range of 60 km.
The diesel-powered APU consists of a hydrostatic drive system, braking system, operation hydraulic system and a back-up system. The basic functions of the APU can be summarised as follows:
- Self-propelled capability of the howitzer
- Mechanised hydraulic operation during deployment
- Ability to assist the prime mover in manoeuvring over rough terrain
The rapid change in the zone of fire by the FH-88 to engage targets outside the primary zone is achieved by:
- Raising the firing platform
- Lowering and steering trail wheels
- Executing pivot turn
- Steering and raising trail wheels
- Embedding spades
- Lowering firing platform
The basic sighting system of the 155 mm FH-88 consists of a cant compensating mount, peri-telescopic sight (×4 magnification) and a direct aiming sight (×6 magnification). However, this can be upgraded to a sophisticated electronic sight and linked to battery fire-control computers.
The trail legs have wheels for ease of handling. They can be opened and closed by hydraulic power and the firing platform is raised and lowered by a double-stage hydraulic cylinder. The trail spades are self-embedding. With a crew of six the gun can be brought in or out of action in less than 1 minute.
The 155 mm FH-88 gun-howitzer can fire standard NATO ammunition such as the M107 HE projectile to a maximum range of 19,000 m. The ERFB HB projectile can be fired to 24,000 m while an ERFB BB can be fired to 30,000 m. The manufacturer claims a range error of less than 0.5 per cent, with deflection error of less than 0.1 per cent at two-thirds of maximum range. The flick rammer can be used to achieve a burst rate of 3 rds/15 s. The sustained fire rate is 2 rds/min for 1 hour.
In addition to firing the standard 155 mm M107 HE projectile and the locally manufactured 155 mm ERFB-HB (Extended Range Full Bore - Hollow Base) and ERFB-BB (Extended Range Full Bore - Base Bleed) projectiles, Singapore has developed a new 155 mm cargo projectile that is now in production for the Singapore Army.
Two versions of this have been developed, High Explosive - Base Bleed (HE-BB) and High Explosive Hollow Base (HE HB). Both of these carry dual purpose bomblets that have been designed to attack the vulnerable upper surfaces of armoured vehicles. Both carry 64 bomblets that are manufactured in Singapore and are fitted with a self-destruct fuze mechanism.
When fired using the C30 combustible propelling charge a maximum muzzle velocity of 800 m/s is obtained together with a maximum range of 27.6 km.
This is now operational with the SAF. Details of the LWH are given in a separate entry.
As a private venture, Singapore Technologies Kinetics developed to the prototype stage the 155 mm Light Weight Self-Propelled Howitzer (LWSPH), which is ballistically identical to the towed 155 mm FH-88 gun-howitzer. This was a test bed only and used in development of the 155 mm/39 calibre Pegasus LWH now in service with the SAF.
Now in service with the SAF is the Singapore Self-Propelled Howitzer 1 Primus (SSPH1).
This full tracked artillery system was developed by the Singapore Defence Science and Technology Agency (DSTA) and Singapore Technologies Kinetics.
It is based on a modified BAE Systems, Ground Systems M109 chassis with a locally developed turret armed with a 155 mm/39 calibre barrel. Details of the SSPH1 are given in a separate entry. This is being offered on the export market but there are no known sales to date. This is the first self-propelled artillery system to enter service with the SAF.