Operation Moduler


Operation Moduler was a military operation by the South African Defence Force during the South African Border War. It formed part of what has come to be called the Battle of Cuito Cuanavale. The SADF objective was to halt a Soviet-backed counteroffensive by the People's Armed Forces of Liberation of Angola on the contested settlement of Mavinga. The advance was halted with heavy Angolan casualties. The South African forces and its UNITA allies then began offensive operations against the Angolan forces, who had retreated back to a defensive line east of the Cuito River with the objective of destroying them once and for all.

Background

During January 1987, FAPLA forces began to increase their air defence network in the Cuito Cuanavale region and by April they had begun to assemble a large force of Soviet-supplied tanks, APCs, trucks and a large number of helicopters and fighter and strike aircraft at the town which indicated the build-up of a new offensive on UNITA. By May UNITA was discussing the situation with the South Africans and by June, SADF military intelligence teams were operating with UNITA teams to monitor the Angolan build up. On 2 June 1987, four combined-arms FAPLA units, departed from the Angolan town of Cuito Cuanavale to capture the UNITA stronghold at Mavinga, which was the gateway to UNITA's capital of Jamba. The offensive was planned by Soviet lieutenant general Pyotr Gusev and code named Operation Saluting October. The FAPLA force was accompanied at the brigade level by Soviet military advisers.
By 15 June, the SADF had formulated a plan to deploy units of 32 Battalion and Valkiri MRLs, for a covert operation similar to Operation Wallpaper, and have the remaining units of 32 Battalion and 61 Mechanised Battalion on standby for an attack on the Angolan brigades. On 22 June, Operation Moduler came into operation with Colonel Jock Harris of 32 Battalion in command but the forces would not be directly involved in the combat and by mid-July, more of 32 Battalion units were ordered to Mavinga with his complete force in place by early August.

Order of battle

South African and South West Africa Territorial Forces from August 1987

  • 32 Battalion - five companies - Colonel Jock Harris
  • three reconnaissance teams
  • one battery MRL
  • one battery mortars
  • two mobile anti-aircraft units.

    South African and South West Africa Territorial Forces from 5 September 1987

20 Brigade - Colonel Deon Ferreira
Battle Group Alpha - Commandant Kobus Smit
  • one mechanised company - 61 Mech
  • one motorized company - 32 Battalion
  • one armoured car squadron - Ratel-90
  • one 81 mm mortar platoon - 4 Ratels
  • one 20mm mobile anti-aircraft unit
Battle Group Bravo - Commandant Robbie Hartslief
  • one motorized company - 32 Battalion
  • two motorized company - 101 Battalion
  • one motorized platoon - 32 Battalion
  • one armoured car squadron - Ratel-90
  • one 81 mm mortar platoon - 4 Ratels
Battle Group Charlie - Major Dawid Lotter
  • one mechanised company - 61 Mech
  • one anti-tank platoon
  • one 81 mm mortar platoon - 4 Ratels
20 Artillery Regiment
  • Q Battery - G5 155 mm howitzers, 4 Stinger teams UNITA, two SA-7 AA teams, 8 14.5mm AA guns, two platoons 32 Battalion
  • P Battery - MRLs plus, one company 32 Battalion, 20 mm AA troop, 2 Stinger teams UNITA, two SA-7 AA teams
  • S Battery - 120 mm mortars plus one platoon 32 Battalion

    South African and South West Africa Territorial Forces from 23 October 1987

Brigadier Fido Smit – Overall Commander
Task Force 10 – Colonel Deon Ferreira
Combat Group Alpha – Commandant Mike Muller
  • 2 x Mechanised Infantry Companies – 61 Mech
  • 1 x Ratel 90 squadron
  • 1 x 81mm Mortar platoon
  • 1 x AA platoon
  • 1 x Engineer Troop
  • 1 x Assault Pioneer Platoon
  • 1 x UNITA Battalion
Combat Group Charlie – Commandant Leon Marias.
  • 2 x Mechanised Infantry Companies – 4SAI 62 mech
  • 2 x Motorised Infantry Companies – 32 Battalion
  • 1 x Ratel 90 squadron
  • 1 x 81mm Mortar platoon
  • 1 x 120mm Mortar battery
  • 1 x Tank Squadron
  • 1 x UNITA Battalion
  • 1 x 20mm mobile anti-aircraft unit
UNITA Liaison Team – Colonel Fred Oelshig
Mobile Air Operations Team – Major Brian Daniel
20 Medical Task Force – Commandant John Lubbe
20 Artillery Regiment – Colonel Jean Lausberg
  • Q Battery - 8 G5s
  • S Battery - 8 G5s and 8 120 mm mortars
  • J Troop - 3 G6s
  • P Battery - 8 MRLs
  • I troop - 4 MRLs
Combat Group Bravo – Commandant Robbie Hartslief
  • 2 x Mechanised Infantry Companies – 32 Battalion
  • 2 x Motorised Infantry Companies – 101 Battalion
  • 1 x Anti-Tank Squadron
  • 1 x UNITA Battalion
  • 1 x Company 701Bn

    UNITA

  • three Regular Battalions
  • four Semi-regular Battalions

    FAPLA/Cuban forces

  • 16 Brigade
  • 21 Brigade
  • 47 Brigade
  • 59 Brigade
Reserve
  • two brigades - West of Cuito & guarding Menongue road and convoys
  • one brigade - Cuito Cuanavale
  • one brigade - East of Cuito at Tumpo

    SADF begins its defensive operations

The South Africans began Operation Moduler on 13 August with Sierra Battery unleashing 120 mm mortar fire on the 47 and 59 Brigades halting their advance at Catato Woods. On 16 August the South African forces were given permission to release their G5 battery and a Ratel-90 anti-tank squadron for operations on the Lomba River. On the early morning of 20 August, South African Valkiri MRLs opened fire on FAPLA forces at Catato Woods alerting the Angolans for the first time that the South African were assisting UNITA. This rocket firing would continue for the next five days on the FAPLA brigades. During this period the Ratel-90 anti-tank squadron was advancing north to Mavinga while between 26 and 28 August, SAAF C-130s flew in the eight G5 battery and their support equipment for deployment to the Lomba River region.
Between 24 and 28 August, a special forces team from 4 Reconnaissance Regiment were sent on a mission called Operation Coolidge. Its objective was the destruction of the bridge over the Cuito River that was used to move FAPLA logistics from Cuito Cuanavale to the brigades to the south-west on the Lomba River. The special forces were dropped off by helicopters 40 km north of the bridge and rowed down the Cuito to the bridge in canoes. After partially setting their demolition charges the team was discovered but managed to escape leaving the bridge partially damaged and unable to be used by vehicles. The team were chased back to their rendezvous point by Angolan troops leap-frogging ahead by helicopters. Despite faulty helicopters, bad weather and Angolan troops, the team was eventually picked up and returned to Rundu. For the first time on 26 August, a SADF forward observer was able to see 47 and 59 Brigade's positions and see the effect of the Valkiri MRL fire on them. The artillery fire was slowing but not halting their advance and this meant the South African MRLs and their protection force eventually had to be moved south of the Lomba River to ensure they weren't cut off.
On 28 and 29 August, SADF planners met at Rundu and a decision was made to send 61 Mechanised Battalion to assist 32 Battalion, released two companies from 101 Battalion and allocated the resources of the SAAF to the operation. With UNITA unable or unwilling to slow the advance of the FAPLA brigades, the Angolans began a fast advance to the Lomba on 29 August which saw them move 40 km in two days. Two kilometres east of the Cunzumbia/Lomba confluence lay a bridge which 21 Brigade would need to cross the Lomba River and they came within 9 km north-west of the objective. 59 Brigade crossed eastwards over the Cuzizi River using Russian bridging equipment and stopped 6 km north of the Cunzumbia/Lomba confluence while 47 Brigade had moved westward to the source of the Lomba River. 32 Battalion and it's Valkiri MRLs moved to the southeast of Lomba/Cuzizi confluence to engage 47 Brigade while its Ratel-90 anti-tank squadron and mortars moved to within 5 km of the same area with the G5s positioned 18 km southeast of the Cunzumbia/Lomba confluence to engage 21 Brigade. On 31 August the South African forces engaged the FAPLA brigades with Valkiri MRLs rockets fired at 47 Brigade halting its advance while later that evening the G5s fired on 21 Brigade halting their advance. 61 Mechanised Battalion's commander Commandant Bok Smit met 32 Battalion's Colonel Jock Harris on 2 September and they would plan the arrival and positioning of 61 Mech forces in the coming days.
A 32 Battalion reconnaissance team was sent behind enemy lines with a forward artillery observer to direct the South African G5 artillery fire and were in position by 2 September while another team had located 16 and 47 Brigade exact position by 4 September. Flying an artillery observation officer on the night of 3 September, a SAAF Bosbok light aircraft was intercepted and shot down by a SA-8 south of the Lomba River killing the two occupants. With the South African force now called 20 Brigade, Colonel Deon Ferreira took command on 5 September with the force divided into Battle Groups Alpha, Bravo and Charlie with units from 20 Artillery Regiment divided between them as necessary. By 7 September, 61 Mechanised Battalion had now reached an area 25 km south-west of Mavinga.
UNITA scouts reported that FAPLA's 21 Brigade was attempting a crossing of the Lomba/Gomba River 12 km east of Cunzumbia on 9 September. Combat Group Bravo sent its Ratel 90 anti-tank squadron forward with a company from 101 Battalion and they encountered a fording BTR-60 that they destroyed but FAPLA artillery counter-attack and it forced the South African units to withdraw 6 km away.
The detached unit of Combat Group Bravo returned on 10 September to the fording site on the Lomba River and again attacked elements of 21 Brigade, but the Angolans' counter-attacked sending in three tanks. The Ratel-90s failed to stop the tanks' advance, so the new Ratel ZT3s were brought into the battle, firing seven missiles with four successful strikes on the tanks. MiG aircraft then arrived over the battle site and forced the South African units to withdraw but they had stopped 21 Brigade's advance.
47 Brigade, based at the source of the Lomba River, moved two battalions with three tanks eastwards to try to make contact with 59 Brigade. On 13 September, the SADF countered this advance by sending two companies from 101 Battalion, eight Ratel-90s and four Ratel ZT3s westwards to meet the FAPLA battalions. Artillery attacked the FAPLA positions first before the small SADF unit attacked and stopped the advance with FAPLA battalions losing 200 dead or wounded but the Angolan tanks led a counter-attack on the Ratels, killing seven SADF soldiers before losing five of their own tanks. The small SADF unit called in their reserve, Combat Group Charlie, and heavy fighting continued for several more hours before a withdrawal was called when further FAPLA tanks were summoned and 101 Battalion company's cohesion broke down and some fled the battle. 47 members of the unit would later be discharged from the army after that event because they were concerned about their deployment against tanks and use as UNITA's "mercenaries". The same SADF unit would again encounter the FAPLA tanks around midnight and destroyed two tanks before withdrawing again.
On 16 September, Combat Group Alpha began its attack in the early morning but its movement was slowed by dense bush and only encountered elements of 47 Brigade who by this time knew the South Africans were coming so by later afternoon Alpha withdrew with no success losing one killed and three wounded. The SAAF kept up the pressure on 47 Brigade with three attacks on 21 September by four Buccaneers around 08h50, four Mirages around 13h00 and four Buccaneers around 17h50. The SAAF conducted a strike against 21 Brigade on 25 September but they missed the target by 200 m but SADF artillery continued their bombardment and the FAPLA brigade took heavy losses. The SAAF sent six Mirage F1CZs to attempt to intercept Angolan MiG-23s on 27 September with one Mirage suffering tail damage from an Angolan air-to-air missile. It returned to SWA-Namibia but crash-landed at the airfield.
47 Brigade received orders on 28 September to cross the Lomba River and meet up with 59 Brigade and then move eastwards crossing the Cunzumbia River and link up with 21 Brigade but the orders were changed later and 21 Brigade was ordered to withdraw north-eastwards. Later that night, President PW Botha, Defence Minister Magnus Malan and the generals flew into Mavinga and met Deon Ferreira and his officers the following day for a briefing. President Botha decided on a more offensive operation and the release of any SADF forces required to destroy the remaining FAPLA brigades east of Cuito Cuanavale.
On 30 September, 47 Brigade attempted to link up with 59 Brigade but their advance was forced back by a SADF artillery bombardment. Plans had been made to attack 47 Brigade on 5 October but radio intercepts reported that FAPLA was about to move from their position, so on 3 October, Combat Group Charlie was ordered to attack with air and artillery support, four UNITA battalions and a 32 Battalion company in reserve. Around 10h17, the Ratel-90s caught the Angolan soldiers crossing the river while the South Africans were attacked by tanks and ZU-23 anti-aircraft guns and the Angolan MiGs flying in support of the ground troops but failed in destroying any SADF vehicles. The South Africans withdrew to resupply around 12h00 and resumed their attack from 14h00 with the Angolans now attempting to retreat across the river taking even more casualties but the battle was over by 17h00. SAAF aircraft attacked 59 Brigade during the day preventing the brigade from coming to the aid of 47 Brigade.
The FAPLA casualties were around 600 killed, the loss of a dozen tanks and vehicles and 47 Brigade no longer a cohesive unit while the SADF lost one soldier killed and a Ratel destroyed and captured a highly sophisticated SA-8 anti-aircraft missile system – the first time the weapon had fallen into western hands. The same day saw plans formulated for 32 Battalion to send units to attack and disrupt the FAPLA supply lines between Menongue and Cuito Cuanavale.