Cross section of a 15-inch battery:Each hardened 15-inch gun mount is around three storeys deep, with ammunition stored in reinforced concrete magazines beneath the gun. Soil overburden estimated at around six feet (2 metres) is thought to cover the gun mounts today.
"Lost" in Singapore for more than 70 years, a hunt for the fortifications for 15-inch artillery guns - dubbed Monster Guns - will get underway soon, spearheaded by curious individuals from Britain and Singapore who are convinced the fortifications lie buried in the Lion City.
As many as three reinforced concrete mountings - some three storeys deep - for giant 15-inch guns built by the British before World War Two could await discovery in Singapore, said a British amateur historian who has spent more than a decade tracing the fate of these and other Singapore coastal gun emplacements.
Lost and found
If found, the rediscovery of the Johore Battery Number 2 gun and Number 1 and 2 guns from the Buona Vista Battery could cause a sensation,and have awaited rediscovery 72 years after the Fall of Singapore. There are similar 15-inch gun batteries, built by the British for the Spanish government remaining in Spain, complete with the guns. Some are open to the public, those on Menorca for example. There you can go into the magazines and into the gun houses.
The Buona Vista No.1 Gun was near the junction of Ulu Pandan and Reformatory (now Clementi) Road. Mowbray Camp now covers the area and is occupied by the Singapore Police Force. But there are visible traces of what may be entrances to the underground magazine (which stores ammunition for the 15-inch gun) and the Battery Plotting Room (which provided fire control data for the guns using sightings of enemy warships seen from coastal observation posts to work out their position on a map) in the camp. Theunderground areas may well still exist.
The position of the No.2 Buona Vista Gun inside a condominium in the Holland Road area could spell a windfall for residents there as the underground structure would add inestimable value to the property. Its presence could also save the property from future land acquisitions from Singapore authorities, as the area sits astride a major road and possible future rail sites.
Amateur military historian Peter Stubbs, 69, used British and Singapore maps and aerial photos dating from the 1940s to the present day to plot the gun positions. He also went through newspaper archives and corresponded with retired British Royal Artillery gunners to painstakingly piece together the fate of Singapore's extensive coastal defences built before WW2.
For example, arcane data such as the trunnion height for each gun, which measured the height of the gun at a certain point on the earth's surface (this was vital for accurate gun firings as the gunners would know where the target ship was in relation to their gun when plotting target data on a map), was compared with ground surveys in Singapore to figure out where the gun mounts could be.
Plan view of a 15-inch gun mount that was built in Singapore.
What happened to the 15-inch guns?
The guns themselves are long gone. What remained after the British spiked the guns in February 1942, stayed in place during the war, and were scrapped by the British in the years following the war.
What may remain of the 15-inch guns are the underground reinforced concrete magazines and power rooms, and the gun-wells into which the guns themselves were mounted. The underground structures extend to a depth of some three storeys, and had three main rooms. The shell store, cartridge store, and the power room. The guns, each of which had barrels as long as a bus, were adapted from naval guns that used to arm battleships.
Mr Stubbs found that Number 3 Gun (northernmost) of the Johore Battery was demolished during an expansion of Changi Airport. This was covered in the press, and photographs of the demolition taken for posterity.
The Number 1 Gun of the Johore battery was covered over by the British in the early 1950s, and a small estate of service married quarters named 'Lloyd Leas' was constructed . Old amahs may well remember it. The Changi Grammar School moved to the area in the early 1960s. The school building has survived, but most of Lloyd Leas was demolished and the area became a prison complex. In April 1991, the long hidden underground areas of the gun emplacement were re-discovered during work being carried out by the prison service. A replica 15-inch Gun was mounted there, and the magazine and power room was outlined in concrete on the ground above.
"Disappeared without a trace"
There is compelling evidence that underground elements of the Number 2 gun lie buried within Changi Airport's fence-line, south of the CAAS airport fire station, waiting to be unearthed and celebrated as a historical treasure.
It is the same story at Buona Vista. Pictures from the 1950s and 1960s, indicate the gun positions were still intact then. Then they mysteriously disappeared without a trace. Demolition of the structures, which would have required extensive excavation, does not seem to have been recorded anywhere. Successive generations of British servicemen who served in post-war Singapore do not remember any demolition. Singaporeans questioned have no memory of any major excavation work at any of the sites.
Both gun batteries were built inland, some distance from the coastline, to protect them from counter-fire from warships.
Mr Stubbs explained: "The Buona Vista, and indeed the Johore Battery, were sited to be inland and out of sight from the sea for very good reasons. The 15-inch guns were indirect fire weapons. This means that they did not have to see targets in order to engage them - as you say difficult to locate and hit. Fire control was provided from remote locations. Any enemy engaging the batteries would not be certain where there fall of shot was landing, thus making enemy fire control more difficult.
"Coast batteries had an important advantage over enemy ships. They were fixed and stable. Ships had to take into account the waves and roll and pitch of the ship. All factors affecting accurate fire. It may surprise you to know that long range coast batteries such as the 15-inch ones had to take into account the curvature of the earth, and the earth's rotation in fire control."
So compelling was the deterrent value of the five 15-inch guns in Singapore - in their time the biggest coastal artillery pieces outside England - against seaborne threats that the invading Japanese forces mounted their attack from Singapore's landward side instead.
Mr Stubbs will be visiting Singapore this year to revisit WW2 sites, and make further attempts to establish the continued existence or otherwise of the "lost" 15-inch gun batteries.
Please stay tuned for more updates. :-)