BEN FRANKLIN 



LENGTH: 48 ft 



BEAM: 20 ft 



HEIGHT: 2 1 f t 



WEIGHT (DRY): 14.3 tons 



OPERATING DEPTH: 2,000 ft 



COLLAPSE DEPTH: 4.000 ft 



LAUNCH DATE: 1968 



HATCH DIAMETER: 30 in. 



LIFE SUPPORT (MAX): 252 man-days 



TOTAL POWER; 750 kWh 



SPEED (KNOTS): CRUISE 2.5 



MAX 4 



CREW PILOTS 2 



OBSERVERS 4 



PAYLOAD: 5 tons 



PRESSURE HULL: Cylindrical shape with hemispherical endcaps: OD 10.33 ft, length 48 ft. Hull material is 1-3/8-in. thick Aldur steel; hemi-heads 



of Welmonil steel of same thickness. Box ring frames 6.3 in. and 5.7 in. deep are spaced 27.5 in. apart to act as internal stiffeners. Twenty-nine 



viewports penetrate the hull (two of these are in the hatches). A 5.5-in.-diam. lock-out chamber (SAS) penetrates the hull topside amidships. The 



hull consists of two asymmetric sections bolted together. 



BALLAST/BUOYANCY: Main ballast is provided by four fiberglass tanks, two on each side of the hull, of approximately eSO-ft^ capacity (48,600 



lb). Variable ballast for depth control ts provided by two pressure-resistant steel tanks in the lower keel section which hold 110 ft^ of water each 



(6,800 lb). Emergency ballast is 6 tons of iron shot stored in bins between the main ballast tanks. This shot is etectromagneticaily held and can be 



dumped as desired. Additionally, a door on the bottom of each bin can be manually opened, totally independent of the electric power. 



PROPULSION/CONTROL: Propulsion is derived from four-25-hp pressure-compensated, fresh water-filled, 22- V, 3-phase, 50-Hz units 



manufactured by Pleuger. The four motors can be rotated 360° in the vertical and can be fully reversed. Two rudders are located aft and are 



electrically controlled and can rotate 30° to each side. By applying reverse thrust on the port motors and forward thrust on the starboard motors or 



vice versa the vehicle can turn in its own length. 



TRIM: Trim is controlled by transferring water between two tanks located at each extreme end of the hull. The tanks are made of steel and hold 50 



ft-* of water each (3,100 lb). The tanks are connected by an overhead vent line in the hull and by transfer pipes beneath the deck. The pilot 



controls two electric pumps which transfer the water at a rate of 1 ,000 Ib/min. The system can obtain a bow angle of +1 . 



POWER SOURCE: Power is supplied by 378 lead acid batteries divided into 4 banks: six-56-V strings & four-28-V strings. An emergency system in 



the hull consists of fourteen-2-V cells of 192-amp-hr capacity. Two static inverters of 336 VDC power the four main motors; two inverters convert 



168 VDC to 1 15 VAC for the pod positioning motors. The main inverters are 3-phase and can be varied from 50 Hz at 70 VAC to 50 Hz at 220 



VAC. 



LIFE SUPPORT: A total of 922 Ib of liquid O2 "s carried. LiOH panels containing activated charcoal are used to remove CO2 by natural convection 



currents in the hull. An active odor removal unit consisting of a chemical absorbing section and a catalytic burning section is used to neutralize 



contaminants not removed by the charcoal. Contaminant levels are determined by Drager gas detector tubes. A manually-operated head macerates 



metabolic waste products and chemically treats and stores them onboard in six tanks of 6,000 tb capacity. A total 4,600 Ib of potable water is 



carried, 1 ,600 lb are carried in super insulated tanks at 21 0°F and are used to reconstitute freeze-dried food. 



VIEWING; Twenty- nine viewports are located throughout the vehicle, they are 6-in. ID, 12- in. OD and 3 in. thick and provide a 90 field of vision. 



A smaller viewport is located topside within a hatch of the SAS. 



OPERATING/SCIENTIFIC EQUIPMENT: UQC (8-10 kHz) magnetic compass, directional gyro, turn/bank indicator, water temperature sensors, 



depth sensor-recorder gage, CTFM sonar, down/forward Fathometer, tracking pinger, two TV's. 



MANIPULATORS: None. 



SAFETY FEATURES: Droppable ballast of 5 tons. Blowing main and variable ballast provides 41 ,000 Ib of lift. Emergency breathing system of 4-hr 



duration each is obtained through a set of six Drager mixed gas (He/02) diving apparatus. Flooding of the hull and escape through an aft trunk is 



possible. Fire extinguishers, flashlights, life raft, releasable buoy, xenon light. 



SURFACE/SUPPORT: Towed or self powered. 



OWNER: Horton Maritime Exploration Ltd., Vancouver, B.C. 



BUILDER: Grumman Aerospace Corp., Bethpage, New York. 



REMARKS: Not operating. Originally designed as PX-15. 



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