Special issue to commemorate the 70th Anniversary of the Battle of ...

Decoding the Enigma of the Fall of the Shing Mun Redoubt Using Line of Sight Analysis
Figure 3 shows the selected vertical profiles of the
Shing Mun Redoubt from PB 401b to PB 403 – a total
ground distance of 494 metres. To move from one
place to another, a person must go up and down steps
here and there inside zig-zagging tunnels of varying
heights and widths, and with roofs punctuated by
vertical air ducts and floors punctuated by rainwater
basins that could have also served as grenade traps. We
may infer that chasing and shooting inside the tunnel
system with “long arms” (such as rifles and MMGs)
was difficult and even hazardous. This supports the
Japanese account that they did not shoot much, if at
all. 11
Shooting had to be confined to areas outside
the tunnels. The dropping of grenades down air ducts
along tunnels was possible, but this might kill both
friends and enemies that were already fighting inside 12 .
Figure 4 shows the vertical profiles of the Command
Centre (Artillery Observation Post) of the Shing Mun
Redoubt and the kitchen below. As explained above,
we believe that Sergeant Mochizuki invaded the OP
from the trench T3 outside the kitchen, which had two
crucibles with stoves and water tanks.
Table 2 and Figure 5 address the questions of mutual
fire support by the defensive structures of the Redoubt.
Table 2 shows the lines of sight from any one PB
or trench vis-à-vis all other PBs and trenches. Each
defensive post was guarded by at least one other post as
long as the other post was manned. Figure 5 shows the
beaten zones of the PBs, OP, and trenches derived from
the assumptions and methods mentioned. The key facts
established are that the entire access road along Jubilee
Dam and its landings along the slopes of Needle Hill
were under the direct fire cover of PB 402, and that the
slopes on the Needle Hill side of the Shing Mun River
Valley were covered by PB401b. The key findings
based on Figures 2 and 3 are:
(1) The Royal Scots’ depiction of the OP as being
separated from the rest of the Redoubt in terms
of tunnel connection was correct: there was a gap
between Charing Cross and Shaftsbury Avenue
(Figure 2).
(2) The Artillery OP/Command Centre of the
Redoubt has more than one exit: T3 was the
nearest and Charing Cross the farther alternative
exit to the 3 hatches. (Figures 2 and 3).
(3) The concrete tunnels inside the Redoubt varied
by height and width and included vertical air
ducts and rainwater/grenade traps (Figures 2 and
3).
We may infer from (3) that the built form prevented
the enemy from easily shooting or undertaking a fast
pursuit during the battle, as lines of sight were near
zero and a person could easily stumble or collide with
something in the darkness.
11
A lot of night attacks used to be made with grenades and edged weapons because that way one reduces the likelihood of ‘friendly fire’ casualties,
especially at close quarters. One also ensures that, without muzzle flashes, the enemy is not sure of the location of an attacker.
12
Evidence of explosions of grenades, all dropped from the east through air vents along tunnels, can be found in a few places along Oxford Street
(north of T4 and near T9) other than within the OP.
SBE
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