# Naval Diving Unit (Singapore)

The Naval Diving Unit (NDU), also referred to as the Naval Divers, is the special forces formation of the Republic of Singapore Navy (RSN) responsible for conducting special operations from sea, air, and land. The formation is made up of six squadrons, specialising in explosive ordnance disposal, underwater demolition, maritime security operations, and combatant craft operations.

## History

In 1959, the British Far East Fleet Clearance Diving Team (FECDT) established a base of operations at HMS Terror Camp, which is the current headquarters of the unit. When the Royal Navy left Singapore on 12 December 1971, the Singapore Armed Forces Diving Centre under the command of Major Robert Khoo was tasked by then Minister for Defence Goh Keng Swee to replace the FECDT. The centre was made up of a group of ten divers selected from over 200 volunteers from the ranks of the Singapore Maritime Command, the predecessor to the Republic of Singapore Navy (RSN). The divers were trained by Lieutenant Victor Rodrigues and were tasked with the maintenance of the Command's naval assets. The SAF Diving Centre became officially known as the Naval Diving Unit (NDU) in 1975.
The unit's first major deployment was during the 1983 Singapore cable car crash, where it retrieved the bodies of four drowned victims. In 1988, with the RSN's rapid growing number of naval assets and an expanding scope of responsibilities, NDU took in its first batch of conscripts to meet its increased manpower requirements. In 1989, Colonel Lau Bock Thiam, then Commander NDU, was tasked with developing NDU's maritime special operations capabilities, which led to the creation of the Special Warfare Group (SWG). Naval divers were involved in the salvage operations following the 1991 SilkAir Flight MI185 crash, and in humanitarian efforts during the 2004 Indian Ocean earthquake and tsunami.
It was a contributor in the multi-national reconstruction efforts in Iraq from 2003 to 2008. Naval divers were also deployed in an operation to search and recover five drowned bodies belonging to members of Singapore's national dragon boating team following a dragon boating incident in Cambodia in 2007.
In 2021, 180 Squadron and Special Operations Boat Task Group were incorporated into the formation. The NDU also celebrated its 50th anniversary.
In December 2022, the NDU announced that Captain (Dr) Chiew Wenqi is the first female navy sailor to be recruited after passing selection.

## Selection and training

In NDU, Full-time National Servicemen (NSFs) and regulars are expected to undergo the same training before they are qualified to become part of the unit.
Recruitment begins with a vocational assessment, whereby NSFs are selected among the thousands that enlist each year. During the primary stage of selection, physical fitness results and medical records are evaluated. Thereafter, an aptitude test is conducted by Applied Behavioural Sciences Department (ABSD) to assess the recruit.
Medical fitness criteria such as a physical employment standard (PES) of A or B1, good eyesight and hearing, and the absence of chronic illnesses that may impede their training will have to be met before potential entrants undergo a battery of further tests that include a swimming and hyperbaric chamber test, as well as another round of psychological evaluation. Those who meet the requirements will then be enlisted into the unit.

### Basic Military Training

Enlistees into the unit will undergo a 9-week long Basic Military Training (BMT) and 22-week long Combat Diver Course (CDC) in Frogman School (FmS), the unit's training branch. In BMT, the recruits experience a modified training programme at Sembawang Camp instead of the Basic Military Training Centre (BMTC) like most enlistees, where they will undergo additional swimming and water survival training. The recruits who meet a satisfactory standard here will qualify for the CDC, or are otherwise posted to other vocations within the Navy.

### Combat Diver Course

The Combat Diver Course (CDC) is known to be demanding. It is conducted in three phases, namely the Foundational, Specialisation, and Advanced phases.
In the Foundational phase, the trainees are introduced to land navigation, outboard motor boat handling, and various underwater confidence tests such as drownproofing and underwater knot-tying. They are introduced to the Sea Circuit, an obstacle course which involves a fin swim, rope climb from the water, run, a confidence jump back into the water, swim, and run, covering 750 metres per round, where three rounds must be completed within 18 minutes. In addition, trainees must achieve 95 points for their Individual Physical Proficiency Test (IPPT), run 6 km in 27 minutes, and swim 2 km in their wetsuits, fins, and a flotation device within 50 minutes, before qualifying for Hell Week at the last week of the phase.
In Hell Week, trainees are subject to sleep deprivation, ice-cold baths, and stressed by machine-gun fire, non-stop physical exertion, team-based competitions, and seemingly nonsensical tasks which are meant to simulate the drawn-out chaos and discord of a wartime situation.
The trainees who clear Hell Week proceed on to the Specialisation phase, where trainees are trained in scuba diving, underwater search and salvage capabilities, as well as land and underwater demolitions.
In the Advanced phase, where trainees learn closed-circuit rebreather diving and shipboard competencies. By the end of the course, around half to three-quarters of the initial intake are expected to have dropped out. Those who graduate as divers are assigned to Clearance Diving Group (CDG). Conscripts are prospectively chosen to be specialists or officers by the end of the course, and will undergo the 8-week Dive Leader Course or the 9-month Midshipman Officer Cadet Course at the Officer Cadet School (OCS) respectively.

### Special Warfare Advanced Training

To qualify as an operator in the Special Warfare Group (SWG), naval divers have to pass the four-month Special Warfare Advanced Training (SWAT). In this course, divers are trained in highly specialised advanced diving techniques to operate effectively in the SWG.

## Organisation

The formation consists of six squadrons which specialise in differing capabilities.
* Special Warfare Group (SWG)
* Special Boat Group (SBG)
* Clearance Diving Group (CDG)
* Underwater Demolition Group (UDG)
* 180 Squadron
* Frogman School (FmS)

### Special Boat Group

Special Boat Group raises, trains and sustains all maritime craft, including the Combatant Craft Large and Combatant Craft Medium which support maritime counter-terrorism operations.

### Clearance Diving Group

The Clearance Diving Group, composed of regular servicemen and Full-time National Servicemen (NSFs), is tasked with helping to preserve the safety of Singapore's vital sea lines of communication, and specialises in improvised explosive device disruption, underwater mine disposal, and explosive ordnance disposal. The group works alongside mine countermeasures vessels and is an integral part of the Naval Explosive Ordnance Disposal Unit. The group is also tasked with underwater security sweeps to ensure that key installations and naval assets are protected from underwater sabotage. The Navy guard-of-honour contingents during the annual SAF Day Parade and National Day Parade are almost exclusively made up of divers from the Clearance Diving Group.

### Underwater Demolition Group

The Underwater Demolition Group, composed only of Operationally Ready National Servicemen (NSmen), is tasked with the demolition of natural maritime barriers, as well as wartime sabotage operations on enemy maritime infrastructure.

### 180 Squadron

The 180 Squadron comprises the Accompanying Sea Security Teams, which conducts compliant ship boarding checks on merchant ships to ensure the safety and security of Singapore's waters.

### Frogman School

The Frogman School is the training institute responsible for developing the maritime special operations capabilities for the Singapore Armed Forces (SAF). It conducts the Basic Military Training, Combat Diver Course, Dive Leader Course, Diver Supervisor Course, ASSET Qualification Course, Special Warfare Advanced Training, and Basic Diving Course.

## Equipment
### Diving gear

* Aqualung Full Range Oxygen Gas System (FROGS)—allows a diver to stay underwater for extended periods of time. A soda lime canister absorbs exhaled carbon dioxide, and the consumed gas is replaced with oxygen from an attached tank. The diver breathes through a mouthpiece connected to the hose and there are no visible bubbles when the diver exhales.
* Clearance Divers Life Support Equipment (CDLSE)—a mine countermeasure rebreather with a minimal magnetic signature which allows for mine disposal operations to a depth of 100m.

### Weapons

Pistols :
| Model | Origin | Caliber | Version |
| SIG Sauer P226 | Germany | 9×19mm Parabellum | P226 E2 |
| Glock 17 | Austria | 9×19mm Parabellum | Glock 17 Gen 3 |
| FN Five-seven | Belgium | FN 5.7×28mm | Mark 1 |
| Sub-machine guns |||||
| H&K MP7 | Germany | HK 4.6×30mm | MP7A1 |
| H&K MP5 | Germany | 9×19mm Parabellum | MP5A3, MP5SD3, MP5K-N, MP5K-PDW |
| Assault rifles |||||
| H&K HK416 | Germany | 5.56×45mm NATO | D10RS D14.5RS |
| M4 carbine | United States | 5.56×45mm NATO | M4A1 SOPMOD Block 1 |
| CAR-15 | United States | 5.56×45mm NATO | Colt Model 653, Colt Model 723 |
| SAR-21 | Singapore | 5.56×45mm NATO | SAR21, SAR21 MMS |
| Sniper rifles |||||
| H&K HK417 | Germany | 7.62×51mm NATO | HK417 16″ |
| M110 SASS | United States | 7.62×51mm NATO | |
| Machine guns |||||
| Ultimax 100 | Singapore | 5.56×45mm NATO | Mark 3 |
| FN MAG | Belgium | 7.62×51mm NATO | |
| STK 50MG | Singapore | 12.7×99mm NATO | |
| Shotguns |||||
| Remington 870 | United States | | 870 MCS |
| Grenade launchers |||||
| M320 GLM | Germany | 40 mm grenade | |
| M203 | United States | 40 mm grenade | |
| Milkor MGL | South Africa | 40 mm grenade | |
| STK 40AGL | Singapore | 40 mm grenade | |

## In popular culture

The first publicly screened production involving the unit was the 1990 Channel 8 drama series titled Navy.
The unit was also the subject of the 2015 Jack Neo film Ah Boys to Men 3: Frogmen which grossed S$7.8 million in the box office. It was filmed on location at the NDU headquarters in Sembawang Camp and some of the trainees and instructors participated in minor roles and as technical consultants.