Swift Boat Sailors Memorial

Specifications

Mark I (PCFs 1-104)

Mark I (PCFs 1-104)

 

Length: 50 foot 1.5 inches
Beam: 13 foot 6.5 inches
Full load draft: Hull: 3 foot 10 inches / Skegs: 4 foot 10 inches / Navigation: 5 foot 10 inches
Height: Main deck at pilothouse: 3 foot 8 inches Top of .50 caliber gun tub: 11 foot 6 inches Top of the radar mast: 16 foot 9 inches
Construction: Hull and superstructure: All-welded, 1/4 inch aluminum alloy plate
Paint Scheme: Deck gray with varying amounts of black added. White service locker lid with black boat numeral Blue circle with white star overlayed on pilothouse overhead Boat numeral in white on either side of the bow and across the stern
Weight: 36,913 lbs. empty / 47,047 lbs. with full fuel and ammunition loaded

 

 

Engines: Two (2) General Motors 12V71"N" Detroit marine diesels, each equipped with two (2) 4-71 turbochargers and N70 type injectors, Each rated at 480 horsepower. SM-118 Hydraulic Marine Gear Clutch with 1.15:1 reduction gears driving two counter-rotating screws.

 

 

Electrical: Two banks of twenty-four (24) volt batteries providing the source of electrical power for main engine starting, general purpose lighting, search lights, navigational lights, and the radar. Each bank charged by its own alternator. Primary supply from the starboard bank, with the port bank in standby. In the case of emergencies, the two banks could be placed in parallel.

An auxillary 6.0 KW Onan, 120 volt, 50 amp, single phase, 60 cycle AC generator providing power to the AN/URC-58 HF radio, signal lantern, refrigerator, freezer, other galley equipment and the AC outlets.

 

 

Electronics: Decca D202 (X-band, 3cm) surface search radar. Maximum range scale: 24 miles. Utilized fixed range rings and a relative bearing presentation. Range discrimination was 30 yards, on the 1.5 mile scale, with a bearing accuracy of 1 degree. Maximum detection range of a small wooden junk: 3 miles, with an estimated 90% detection of small junks at 1 mile. In average sea conditions, a 90% detection rate for steel hulled trawlers was assumed to be 5 miles.  Power consumption was 200 watts DC.

Raytheon DE176A Fathometer: Dual range. 240 foot maximum depth reading

AN/URC-58 HF radio: 2 to 15 MHZ. Upper/Lower sideband, AM or CW. Output: 100 watts. Input Power: 120 VAC, but capable of 24 VDC operation. Of little or no effective use during 1967.

AN/VRC-46 VHF FM radio: 30.00 to 79.95 MHZ. Installed during 1967. Primary Coastal Surveillence Center guard channel communications.

AN/PRC-10/25 VHF FM, portable field radio: 30.00 to 79.95 MHZ . Primary communicatons until the AN/VRC-46 radio was installed.

AN/URC-4 Survival/Emergency radio

 

 

Other: Danfort/White magnetic compass. Installed in the pilothouse

Rotatable spotlight: used to illuminate targets at 250 to 300 yards range. Mounted on the pilothouse overhead and controlled by the helmsman

A 6 inch portable signaling lantern: visible at a 4 mile range, when used from the guntub

Hand held observers magnetic compass

 

 

Armament: Twin .50-caliber Browning machine guns (heavy barrels), installed in a Mark 17/Mod 1 manually operated, twin-scarf-ring mount. Capable of firing at 450-550 rounds per minute. Equipped with ammo trays with 500 to 600 rounds per gun. The machine guns were located on the boat centerline, in a guntub, mounted on top of the pilothouse. The maximum range was in excess of 7,000 yards. The effective accuracy decreased rapidly in excess of 2,000 yards, but effectiveness at 1000 yards and under was excellent. Typical patrol ammunition load carried was between 20,000 to 25,000 rounds.

81mm Mark 2/Mod 0, trigger fired naval mortar with a .50-caliber Browning machine gun (heavy barrel) fixed atop it. The machine gun was equipped with an ammunition tray/can containing 100 to 300 rounds. The combined weapon mounted to a centerline tripod on the fantail with a two way swivel.

      - Range of the 81mm mortar: 3,940 yards elevated and 1000 yards direct

      - Trigger fired capacity: 10 rounds per minute.

Typical 81mm ammunition load carried on board in the two main cabin floor lockers and the stern mounted ready service locker was:

     - High Explosive with point detonated fuse: 80 rounds

     - White Phosphorus with point detonated fuse: 15 rounds

     - Illumination with timed fuse: 20 rounds

Various crew member weapons included: M-79 grenade launchers, M-16 rifles, a 12 gauge Ithaca riot gun, .45 and .38 caliber pistols, various types of hand grenades (fragmentation, concussion, thermite and red, yellow and green smoke), and a Very Pistol Flare Gun.

 

Turning radius: 75 yards when cruising at 20 knots

 

 

Stopping Distance: 2 1/4 boats lengths (112 feet) in 9 seconds, from maximum speed

 

 

Fuel: 828 gallons, diesel or JP-5 in an emergency. Stored in three fuel tanks (2 aft, 1 amidships)

 

 

Speed: 32 knot designed maximum

Actual engine RPM versus speed data varied widely from boat to boat depending on the type of fuel used, loading of the boat, and calibration of the remote engine tachometers. The maximum speed was usually obtained with the engines turning in the neighborhood of 2200 RPM. Accurate knowledge of speed thru the water was not a navigational necessity when operating in the rivers and/or close to the shoreline.

The height of the sea significantly curtailed the speed capabilities of the PCF. This effect varied with the course of the PCF relative to the direction of the seas.

 

 

 

 

Mark II (PCFs 137-139, 813, 814 &amp; 816)<br /><br />

Mark II (PCFs 137-139, 813, 814 & 816)

 

Length:

51 foot 3.75 inches

Beam:

13 foot 7 inches

Full load draft:

Hull - 3 foot 10 inches, Skegs - 4   foot 10 inches and Navigational - 5 foot 10 inches

Construction:

Note:

hull/superstructure were of   all-welded, 1/4 inch aluminum alloy construction

All deck plating, bulkheads, and   other structural members were 5086-H321 aluminum alloy for both sheets and   plates. All extrusions were made using 5086-H311 aluminum alloy.

Two magnesium anodes were located   on the stern, below the water line, and provided the means for reducing   underwater electrolytic corrosion.

Bow height was raised by one (1)   foot and the pilothouse was moved aft by approximately three (3) feet, from   the Mark I construction plans design

Weight:

34,934 lbs. empty - 45,093.8 lbs.   with full war load of fuel and ammunition

Displacement:

43,035 lbs.

Engines:
 
 
 
 
 
  Propellors:

Two (2) General Motors   12V71"N" Detroit marine diesels; port model #7122-3000, starboard   model #7122-7000, each equipped with two 4-71 blowers and rated at 480   horsepower, when using the N70 type injectors, MG-512, Twin Disk, Hydraulic   Marine Gear Clutch with 1.5:1 reduction gears and driving two   counter-rotating bronze screws. Each engine was equipped with an MP130R, 180   gpm bilge pump.
 
  Two (2) 28x26 inch/pitch, 2.25" bore; one right hand rotation, one left   hand rotation (factory configuration).

Electrical: DC
 
 
 
 
  AC

5 - 12 vdc batteries (Delco 761 -   205 amp hour) provide the main source of electrical power, including main   engine starting, load and AC generator start. They were arranged as (2) 24   volt battery banks, each charged by its own alternator. The DC system was a   two wire, ungrounded system.

- 6.0kw diesel Onan generator,   model 6MDJB-3, 120 volt, 50 amp, 60 Hz AC, water cooled.

Electronics:

Decca D202 (X-band, 3cm) surface   search radar, maximum range scale of 24 miles, with fixed range rings and a   relative bearing presentation. Range discrimination was 30 yards, on the 1.5   mile scale, with a bearing accuracy of 1 degree. Maximum detection range of a   small wooden junk was 3 miles, with an estimated 90% detection of small junks   at 1 mile. In average sea conditions, a 90% detection rate, for steel hulled   trawlers, could be assumed at 5 miles. Power consumption was 200 watts DC   only.

Raytheon DE-736 Fathometer - dual   range (240 foot maximum depth)

AN/URC-58 SingleSideBand radio, 2 to 15 Mhz, could   operate on upper sideband, lower sideband, AM or CW. Output was 100 watts.   This was the PCFs primary communications equipment and was used to guard the   M/T reporting net (S-3) for long range - boat to base communications. This   radio normally operated on 120 volts DC power but could be operated on 24   volt DC if necessary.

AN/VRC-46 FM radio, 30.00 to 79.95   Mhz (short range - boat to boat or boat to shore for coordination with other   units).

Fuel:

828 gallons, diesel or JP-5 in an   emergency, in three fuel tanks (2 aft - 279 galllon capacity, 1 amidships -   270 gallon capacity)

Potable Water:

51 gallons in a rectangular   stainless steel tank

Mark III (PCFs 691-695)

Mark III (PCFs 691-695)

 

Construction:

Hull/superstructure were of all-welded, 1/4 inch   aluminum alloy construction

All deck plating, bulkheads, and other structural members were   5086-H321 aluminum alloy for both sheets and plates. All extrusions were made   using 5086-H311 aluminum alloy.

Two magnesium anodes were located on the stern, below the water line,   and provided the means for reducing underwater electrolytic corrosion.