THE LAST SURVIVORS
COMPILED BY JERRY PAYNE WO RNZN (RET���D)
W
hat became of the last of the HDML���s that served
our country, patrolling our coast well beyond their
intended life expectancy?
Most of us older boaties will remember the black
and grey 72ft wooden motor launches known as Black Boats that
the Navy used for fisheries protection from the 1950���s, until they
were replaced in the mid-1980���s with a larger steel vessel. This
is a brief history of those amazing boats and the story of one in
particular: Q1184, (later HMNZS Paea P3552).
DESIGN
Prior to WWll the British Admiralty recognised that there was a
need for a purpose-built vessel to assist in the defence of ports
around the British coast. The design criteria required a wooden
vessel, with good seakeeping capabilities, the ability to turn
inside the turning circle of a submerged submarine, and capable
of dropping depth charges.
Early in 1939 a design was submitted by WJ Holt, Chief
Constructor of the Naval Construction Department at the
Admiralty. It was 72ft in length with a beam of 16ft and a
draught of 5ft. There was accommodation for six ratings in the
for���ard mess, two petty officers amidships and two officers aft.
Armament consisted of twin 20mm Oerlikons, twin Vickers
machine guns and six depth charges.
The design was approved, and the first Harbour Defence
Motor Launch was built at McGruer boatyard in Clynder,
Scotland, and commissioned on September 1, 1940. The Britishbuilt launches were powered by twin Gardner 8L3���s of 152 bhp
each, giving a top speed of 12 knots. Subsequently, 486 HDMLs
were constructed, mainly by yacht builders in the UK and other
allied countries.
30 Professional Skipper March/April 2013
The vessel proved to be
an excellent seaboat, and
the flared bow prevented
all but the heaviest
seas from coming
aboard. The round bilge
amidships gave the vessel
ch
a tendency to roll, much
ny
to the discomfort of many
low
who sailed in them. To allow
ility,
the greatest manoeuvrability, the
f h
keelson stopped short of the stern b
by
some 13ft and this, coupled with the large rudders that were
fitted, allowed them to turn almost within their own length. The
downside of the shortened keelson was that they were difficult
to steer in a following sea.
The hull was built of planked mahogany using double diagonal
construction with oiled calico between each skin. This was
riveted to timber frames running from the keel to the gunwale
and further strengthened by longitudinal stringers, giving a very
strong hull. Five watertight bulkheads athwartships divided the
hull into six compartments, any one of which could be flooded
and the boat remain afloat.
There were six bunks in the for���ard mess: four on the port side
and two to starboard. A small galley was situated on the starboard
and cooking was done on a small oil fired stove. Four fuel tanks
were situated aft of the for���ard mess. Amidships was the engine
room with the two main diesel motors and an auxiliary single
cylinder Gardner for charging the batteries and the fire and bilge
pump. Above the engine room was the chartroom. It contained
the chart table, a casual berth and a second steering position.
