• About
• Education
• Events
• USS Pampanito
• Support
• Visit

SECTION A1.
GENERAL REQUIREMENTS.

The arrangement of the machinery installation for the 80-foot and 78-foot hulls shall be as follows:

One specific set of contract plans applies to each installation as specified in section S1 herein. Hereinafter any statement applying particularly to one hull will be followed by reference to the proper alternate. Where no reference is made to an alternate, it shall be understood that the statement applies to all three alternate designs.

It is further the intent of these specifications to obtain vessels that are essentially duplicates of previous vessels built by the ship- builder except as otherwise specified herein.

The general arrangement of machinery shall be as indicated on the contract plans, except for such modifications as may be agreed upon between the shipbuilder and the Bureau from time to time, in the form of developments or changes under the contract. It is intended that the machinery arrangement shall provide the best military protection for all vital equipment.

The main propulsion plant shall consist of three Packard gasoline marine engines arranged in general as follows:

The main engines shall be electrically started, with manual stop, start, and reverse controls from the engine room; and with remote controls from the pilot house for the throttles only. All main engines shall drive right-hand propellers turning clockwise in the ahead direction, when viewed from aft of the boat looking forward. The exhaust from the main and auxiliary engines shall be led outboard through water-jacketed pipes with water spray in such a way that will not permit back flow of water into the engines. In addition to the main machinery there shall be installed an electric plant, a heat generating plant, necessary pumps, and such other machinery, tools, instruments, and apparatus as specified or described herein, together with such others as may be necessary to complete the machinery installation in accordance with specifications and plans.

List of machinery and equipment to be supplied by the Government (Bureau of Ships) for installation by the shipbuilder.

The items of Government furnished machinery and equipment which will be delivered to the works of the shipbuilder for each vessel are as follows:

The shipbuilder shall install, at his expense, these items provided by the Government, in accordance with plans approved by the Bureau of Ships. He shall supply and install at his expense all installation piping, valves, fittings, electric cables and wiring, devices, and appurtenances necessary to make a complete and satisfactory working installation. The shipbuilder shall be responsible for care of all Government furnished machinery and equipment from the date of arrival at the shipyard until delivery of the vessel to the Government. Unsatisfactory operation of the Government furnished machine after installation shall be the responsibility of the shipbuilder and/or machinery contractor. The shipbuilder shall be responsible for proof that the unsatisfactory operation is not due to defective installation and/or deterioration or handling during storage.

General features.-It is the intent of these specifications to secure a machinery installation suitable for the purpose intended and comparable to machinery installation in previous boats furnished by contractor except as otherwise specified herein. It is the further intent of these specifications to achieve simplicity, accessibility for inspection, removal and assembly, economy of weight, space and cost, with a minimum of required maintenance insofar as practicable for the machinery installation. The design, construction, and workmanship, and installation of all machinery and machinery appurtenances shall be such that a minimum practicable noise level will result under all operating conditions. Any part of this equipment pertaining thereto, whether fully described in the specifications or omitted, or imperfectly described, but necessary for the proper completion of the installation, shall be furnished by the shipbuilder the same as if they had been specifically covered.

It is evident that it is not practicable to enumerate in the specifications all details or fittings or appurtenances of the equipment, nor is it necessary to do so, it being understood that they

The contract specifications are not to be departed from except by approval of the Navy Department. If such departure should be made without approval, the Navy Department shall be at liberty at any time before or after completion of the work, to cause the part affected to be removed, remade, or replaced, and this work, together with all parts injured by the corrections shall be made good by, and at the expense of, the shipbuilder.

Defects in design, materials, or workmanship which may develop during the construction and tests of the equipment shall be made good by and at the expense of the shipbuilder excepting Government furnished equipment. Any dispute relative to the intent of specifications or concerning any omissions or imperfections shall be referred to the Navy Department, whose decision shall be final. The machinery and electrical contractor will, immediately upon being advised of the builders of the vessels in which the machinery and/or equipment is to be installed, contact the shipbuilders and assure himself and the Bureau that the machinery and/or equipment which he proposes to furnish is suitable for the purpose intended. He shall maintain this contact throughout the building period and endeavor by every means in his power to anticipate and eliminate any points of conflict as regards installation.

Any question of responsibility or procedure which cannot be amicably adjusted between the shipbuilder and the machinery and electrical contractor shall immediately be referred to the Bureau of Ships whose decision, so far as regards matters under this contract, will be final.

Critical materials.-Prior to ordering materials, the contractor shall consult the Supervisor of Shipbuilding with reference to all possible substitutions for critical materials in accordance with the Bureau's current instructions.

The use of critical materials shall be kept to a minimum with all substitutions being made on a not-to-delay-ship basis.

Special specifications.-Numbers and titles of sections of the General Specifications for Machinery are used as headings, throughout the Special Specifications for convenience in finding subjects. When the title is accompanied by an issue date the section applies as including Navy Requirements.

Inspection.-Inspection of all materials under these specifications shall be made by naval inspectors or supervisors of shipbuilding. In order to expedite the construction as much as possible, the Inspector or Supervisor may, subject to approval of the Bureau, substitute other requirements which tend to accelerate construction. The construction of the equipment and appurtenances shall be open to inspection at all times to a naval inspector.

Finished articles to be incorporated in the work may be inspected at the works of the manufacturer at the request of the shipbuilder.

SECTION S1.
PLANS AND MATERIALS.

The following is a complete list of applicable plans accompanying and forming a part of these specifications:

675929-44-6

ELECTRICAL STANDARDS

SECTION S1-1.
PLAN REQUIREMENTS.

Working plans.-Working plans for the installation of machinery and equipment as covered by these specifications shall be prepared by the shipbuilder. The shipbuilder shall submit to the Supervisor of Shipbuilding or the Bureau, if necessary, for approval plans which shall be in sufficient detail to permit the Supervisor of Shipbuilding, or the Bureau, if necessary, to obtain a definite conception of the shipbuilder's intention, and shall show particularly overall dimensions, weights, material of construction, fittings, pressures and temperatures in addition to any other pertinent data concerning the equipment. Plans shall conform to Bureau Standards as specified under "Finished Plans" herein.

These diagrams shall list all equipment giving capacities, approximate weights, R. P. M., pressures, etc.

In addition to the above plans, such other working plans as may be required to represent the complete design shall be furnished by the shipbuilder. Two copies of all working plans shall be forwarded to the Bureau by the Supervisor immediately after approval.

Finished plans.-A complete set of finished plans shall be furnished within 3 months after completion of the vessels. These plans shall cover each and every part of the equipment described above which is subject to replacement or renewal during the life

The plans shall be on a Navy standard size sheet of 27 inches wide by 40 inches long with a blank space of 1 1/2 inches wide by 4 inches long on the horizontal in lower right hand corner of each sheet. If special size sheets are required to show one item complete for such assembly plan, etc., these may be increased in length from 40 inches up to 80 inches. Any number of parts may be shown on a 27 by 40 inch sheet, provided they are spaced so that each part can be readily identified. Mechanical and electrical equipment plans shall be furnished on a separate sheet group so that no mechanical equipment part will be shown on an electrical equipment part sheet, or vice versa. List of material on assembly plan shall show the part number and the corresponding plan number upon which the part is detailed. A complete master list shall be furnished, showing all part and plan numbers of plans for identification. The master list shall have a blank column on right-hand side for adding BuShips number.

The Navy contract number, plan description, and vessel identification number shall be shown on each sheet.

Two blueprint copies representative of the type of finished plans that are to be furnished shall be submitted to the Bureau of Ships, Navy Department, Washington, D. C., for approval prior to delivery of complete set of finished plans.

On standard commercial fittings such as valves, gages, etc., no plan will be required if catalog literature showing details of construction is available. All such catalog literature must be bound together in a suitable, indexed folder, and the model or type of material furnished must be indicated in each case.

Two bound copies of the catalog shall be furnished to the Bureau of Ships. The finished plans for the electrical installation shall conform to the requirements stated above, except that the information shown shall include the following:

1. For motors.-The plan of each motor shall contain complete identification data and follow the plan, BuShips No. 10-T-2124-L.

2. For motor controllers.-The plan of each motor controller shall contain complete identification data and shall in general follow the standard motor

3. List of lighting fixtures, lighting and power system wiring appliances including quantities and weights. (This list shall show BuShips plan number, catalog number, manufacturer, and other data as necessary to facilitate additional purchases and to permit determination of the type of equipment used and the materials of which it is constructed.)

4. Reproduction of plans required under working plans herein.

5. Record of electrical installation in bound book form.

One set of prints of principal plans shall be supplied each vessel by the shipbuilder. This list shall be compiled by the Supervisor of Shipbuilding. In order to assure proper data for training, maintenance and operation, all plans, instruction books and descriptive pamphlets specified for delivery to each boat shall be delivered prior to the completion date. (Working plans shall be substituted for finished plans, if latter are not available at time of delivery of the vessels.)

Instruction books.-Instruction books for principal items of shipbuilder furnished equipment shall be supplied as follows:

Instruction books for engineering piping systems.-The shipbuilder shall furnish instruction books for the operation of the engineering piping systems and related equipment. Instruction books shall be prepared in a form that may be readily understood by personnel of limited experience and shall contain complete but only sufficiently detailed instructions to serve this purpose. The book shall contain information pertaining to the following systems:

(1) A complete diagrammatic representation of the system illustrating by notes or by numbered or lettered symbols each component part. Directions of flow shall be given on the diagram. A table of symbols with the corresponding names and functions of component parts shall be provided. Use shall be made of colors and other devices as practicable to simplify the study and understanding of the system by showing clearly the

(2) Tabulations of the principal parts, the designed functions and the designed limitations of the systems.

(3) Detailed directions for operation of the system with reference to the diagrams and illustrations, including instructions for alternative methods of operation to be used in event of failure or damage to parts of the system.

Instruction books for engineering piping systems and related equipment shall be prepared in accordance with all applicable requirements of section S1-1 of the General Specifications for Machinery, dated 1 March 1941, and shall be submitted for approval in preliminary form. A master instruction book will not be required. Copies of instruction books shall be delivered as follows:

SECTION S1-2.
MATERIALS, WORKMANSHIP, AND INSTALLATION.

Materials used in the construction of machinery equipment and fittings shall be of a quality in accordance with applicable specifications listed herein.

Where the manufacturer's certified tests are accepted in lieu of Navy chemical and physical tests, the manufacturer shall assume full responsibility for the service requirements of the material certified. Should the material fail in service, the manufacturer shall replace it at his own cost with a satisfactory material.

All workmanship shall be thorough and substantial in manner, with the best Marine standards and policies adhered to.

Operation and maintenance efficiency shall be the guiding objective in the installation. Any of the items herein not in accordance with the highest of standards indicated shall be removed or changed at the discretion of the Supervisor.

SECTION S1-3.
BOLTS, STUDS, SCREWS, NUTS, ETC.

Threaded parts shall be in accordance with the standards of the Inter-Departmental Screw Thread Committee.

This section of the General Specifications for Machinery issue in effect of date of contract shall serve as a guide insofar as acceptable welding and brazing procedure is concerned. It is not intended that Navy requirements be strictly adhered to; inspection shall be relaxed to permit acceptable practice.

SECTION S8.
TRIAL REQUIREMENTS.

When each boat has been completed in every essential respect as required by the contract, and when the boat builder shall have made sufficient tests to be reasonably sure of satisfactory operation without excessive heating and without additional adjustment, the boat shall be subjected to a material inspection and acceptance trial, under the supervision of the Board of Inspection and Survey or a subboard appointed by it.

Trials shall be of three types and shall be run under the following conditions and as noted below. Trials to be conducted with full military load displacement on a trial course specified by the Bureau of Ships except as otherwise noted herein. During these trials, the performance of the engines shall be observed and records made of the boat speed, and all engine instrument readings as well as records of any vibration, erratic running, noise, and any sign of distress or overheating of any parts; also the general performance of the complete machinery installation. A record shall be made of the total displacement, weights aboard, draft forward and draft aft at the beginning and end of each test. Two copies of these test records shall be forwarded to the Bureau of Ships, Navy Department, Washington, D. C.

-Class Type Trials shall be conducted on the first vessel to be delivered under the contract and shall consist of the following:

The vessel shall be weighed on a certified set of scales upon completion. The weight figure thus obtained together with a complete itemized analysis thereof shall be included in the trial report of the vessel.

The boat shall be docked just prior to the trials, bottom cleaned and painted and propellers checked. Just prior to getting underway each day a check shall be made to insure the presence on board of full military load and its displacement determined. Where actual military equipment is not available, it shall be compensated for by additional added weights. The trials of the first boat shall consist of the following tests:

575929-44-7

(b) Standardization.-These tests shall be run over a measured mile, three runs being made in alternate directions at each speed. These tests shall be run on one, two or three engines from the lowest speed practical up to that corresponding to 2,500 r. p. m. on each engine. Sufficient tests shall be run to obtain smooth curves of shaft r. p. m. and engine manifold pressure vs. boat speed.

(c) Full speed test.-This test shall be run for one hour with all propelling units operating at a maximum of 2,400 r. p. m. The boat speed, engine manifold pressure, fuel and lubricating oil consumption shall be recorded.

(d) Cruising speed tests.-Each of these tests shall be run for two hours. The boat speed, fuel and lubricating oil consumption shall be recorded for each of the following two-hour tests:

(e) Auxiliaries tests.- During tests (c) and (d) the satisfactory operation of all auxiliary engineering equipment shall be demonstrated. The number of electric generators in operation together with their loads and the combined load shall be recorded.

(f) Silent running tests.-These tests shall be conducted on a calm night operating one, two and three engines at a boat speed from 10 to 20 knots and the audible range of engine noise recorded for each condition.

(g) Reverse gear and clutch tests.-The satisfactory operation of clutches and reverse gears shall be demonstrated during maneuvering tests of the boat.

(h) Acceleration test.-With each engine idling at 600 r. p. m., the throttles shall be thrown wide open and the time required for the engines to reach 2,500 r. p. m. recorded. This test shall be run over a course having markers at 100-yard intervals and a record made of the time to pass each marker as well as the engine r. p. m. at that point.

(i) Retirement maneuver tests.-With engines idling at 600 r. p.m., the throttles shall be opened up wide and simultaneously the helm put hard over changing course 180°. The boat shall be steadied on the reverse course and allowed to accelerate. The time to complete the 180° turn and the time to accelerate the engines to 2,500 r. p. m. shall be recorded. One test shall be made turning to the right and another test made turning to the left.

(k) Turning tests.-With the boat proceeding at each of 3 speeds corresponding to 600 r. p. m., 2,000 r. p. m., and 2,500 r. p. m., the helm shall be put over as rapidly as possible and the boat permitted to swing though a full circle. The time at each 90° and the diameter of the circle shall be recorded. At each speed one test shall be made turning to the right and another turning to the left.

(l) Additional trials.-Any additional trials and inspections, which may be required by the Board of Inspection and Survey (or a subboard appointed by it) to demonstrate suitability of the boat and equipment, shall be conducted by the boat builder.

(m) Post trial examination.-After the above trials have been completed, the boat will be returned to the works of the boat builder when the machinery will be inspected by the machinery contractor's representative for post trial examination as required by the Bureau of Ships or as directed by the Board of Inspection and Survey. The boat builder shall provide dockage space without charge and shop services and handling facilities, if required during the post-trial examination period.

(n) Other trials.-All other tests or trials required by the Bureau of Ordnance or other Bureaus shall be conducted after delivery of the boat. Where such tests or trials involve boat builder responsibility, they will be conducted in the presence of his representative and the boat builder shall make good at his own expense all defects and deficiencies for which he may be responsible.

First boat of each squadron trials.-Shall be run on a Government measured trial course approved by the Supervisor of Shipbuilding, at full military load displacement and shall consist of (b) (for 3 engines only), (c), (e), (g), (k), (l).

Subsequent boats' trials.-Trials of subsequent boats shall be run on a course approved by the Supervisor of Shipbuilding, at 100,000 pounds displacement and shall consist of (c), (e), (g), (l) above.

SECTION S16-1.
FLOOR PLATES, GRATINGS, LADDERS, ETC.

All access trunks and escape hatches in machinery space shall be in accordance with the Detail (Hull) Specifications and contract plans. Floor of machinery space shall be water and oil resistant plywood similar to BuShips Specification 39P15 (INT), 1 October,

SECTION S19-1.
PAINTING AND PRESERVATION.

Painting shall be in accordance with appendix 6, dated June 1943.

All piping shall be thoroughly cleaned before assembly, and protected against dirt and foreign material during construction. After installation and before using, each piping system shall be adequately flushed with the type of fluid to be used in the system, and then fresh fluid used for operation. After flushing, all strainers shall be opened and cleaned.

SECTION S24-7.
REMOTE INDICATING MAGNETIC COMPASS EQUIPMENT.

Remote indicating magnetic compass equipment will be furnished by the Bureau of Ships and shall be installed by the shipbuilder in accordance with approved detail plans. The Government-furnished equipment will consist of the following Flux Gate Induction Compass Equipment:

All wiring, foundations, mountings, and accessories necessary for the satisfactory installation of the equipment in the vessel shall be provided and installed by the shipbuilder.

A 24-volt, 2-wire, direct-current supply will be required from the main distribution panel located in the engine room.

SECTION S28-1.
DESIGNATING AND MARKING, MACHINERY INSTALLATION.

Principal piping shall be marked in a suitable manner for ready identification as approved by the Supervisor of Shipbuilding.

SECTION S28-2.
DESIGNATING AND MARKING, ELECTRICAL INSTALLATION (dated 15 December 1943).

Power, lighting, I. C. and F. C. cables shall be marked in accordance with contract plans.

The weight of all on-board machinery items to be furnished by the Government shall not exceed 14,700 pounds for alternate (a) engine installation, 14,325 pounds for alternate (b) engine installation, or 14,425 pounds for alternate (c) engine installation. The weights of the individual items shall be approximately as follows:

Items common to all installations-

The various contractors shall submit a list of estimated weights showing the dry and wet unit weights (with separate weights for fresh water, sea water and lubricating oil) for each of the individual items listed above. These weights shall be itemized for each unit with its attached equipment, and for each unattached accessory. The list shall also include the net and gross weights of spare parts and tools per set, divided into onboard and ashore totals.

Upon completion of the first or one of the first of each item or unit listed above the contractor shall determine and submit immediately the actual weights thereof. These actual weights are to be itemized for the unit and its attached equipment and for each unattached accessory, but need not include contained liquids.

The above estimated and actual weights are to be submitted to the Bureau of Ships, Navy Department, Washington, D. C.

SECTION S31-1.
SPARE PARTS.

All spare parts for shipbuilder furnished equipment will be provided under separate contract by outfitter activity. All spare parts are to be delivered concurrently with each squadron. The

A parts list shall be furnished by the shipbuilder for all shipbuilder furnished equipment.

SECTION S38-1.
HEATERS, GASOLINE.

See Detail (Hull) Specifications.

SECTION S38-3.
BRACKET FANS.

Three ventilating bracket fans similar to the General Electric Marine type 95 by 512 (24-volt) or equal shall be installed; one in the chart house and two in the engine room as directed by the Supervisor of Shipbuilding.

These bracket fans shall meet the requirements of Navy Department Specification 17F6.

SECTION S39-1.
HEAT INSULATION AND LAGGING FOR PIPING AND MACHINERY.

Adequate heat insulation shall be provided to reduce radiation in particular from main engine exhaust system. The engine exhaust manifold shall be water jacketed as approved by the Bureau of Ships.

SECTION S41-3.
MAIN PROPULSION AND AUXILIARY GASOLINE ENGINES.

General-main and ship's service gasoline engines.

A. The gasoline engine propulsion and auxiliary equipment to be furnished by the Government and installed by the boat builder will consist in general of two types of equipment as follows:

Main propelling engines.

A. Three main propelling gasoline engines will be furnished for each vessel in accordance with the following:

Auxiliary generator sets.

A. Two auxiliary gasoline generator sets per vessel will be furnished in accordance with the following:

Co-ordination-shipbuilder and machinery contractor.

D. Close coordination between the shipbuilder and machinery contractor will be necessary to assure that the machinery will fit into the vessel and there will be no delay in installing the machinery. The bulkheads and machinery foundations should not be located in the vessel until certified machinery installation plans are received from the machinery contractor. Lubricating-oil and fresh water pumps shall be removable without moving engines.

575929-44-8

Service and spare shafts will be furnished by the Government. These shafts will be 2 1/4 inches diameter, heat treated, precision straightened, K monel bars which conform to Navy Department Specification 46N5. The Government will furnish one set, consisting of 3 shafts, per vessel for installation as service shafts and one set, consisting of 3 shafts, for every 2 vessels for onboard spare shafts. Service and spare shafts will be machined by the Government and shall be installed by the shipbuilder. The Government will furnish shaft accessory parts such as propeller hex nuts and locking jam nuts, coupling nuts and locking devices.

The propeller shaft-engine coupling will be furnished by the Government.

The propeller and engine coupling ends of the shafts will be taper splined. A taper of 1 inch per foot will be used on shaft tapers. A plan showing the taper spline details will be furnished by the Bureau of Ships at a later date.

The propeller hub will not exceed 8 1/2 inches in length.

Within two weeks from the date of award of contract, the ship-builder shall notify the Bureau of the exact lengths of shafting that the Government will be required to furnish.

The stern tube gland shall be of a floating type, rigidly restrained from rotation, but free to float so that it will not influence shaft alignment. The struts and stern tubes shall be manganese-bronze or aluminum-manganese-bronze castings.

SECTION S43-2.
BEARINGS, PROPULSION SHAFTING.

Stern tube and strut bearings shall be of the "Cutless Rubber, Full Molded, Water Lubricated Type." These bearings shall be furnished and installed by the shipbuilder.

The shipbuilder shall supply Bureau approved "Cutless Rubber," bearing pullers to the amount of one for each three vessels delivered.

SECTION S44-1.
PROPELLERS.

There shall be 3 aluminum-manganese-bronze right hand turning propellers per vessel. The diameter of the propellers shall not exceed 30 inches. Hub length will not exceed 8 1/2 inches.

The Government will furnish one set, consisting of 3 propellers per vessel for installation as service propellers, and one set, consisting of 3 propellers, per vessel for stowage aboard as spare propellers.

Propellers for test purposes and replacements for propellers damaged on trials will be furnished by the Government from stock spares upon request of the Supervisor of Shipbuilding to the Bureau of Ships.

The Government will supply one propeller puller for each vessel.

The arrangement of lubricating oil system for the main engines shall be as approved. The reverse gear and clutch unit is lubricated from the engine oiling system. Each V-drive used in alternate (a) shall have independent lubricating oil system including lubricating oil tank. The lubricating oil tank of adequate size shall be furnished by the shipbuilder.

The lubricating system of each engine shall be independent of every other engine so that contamination of one will not affect any other. There will be no lubricating oil transfer system.

The main engines shall have individual lubricating oil sump tanks of about 30 gallons capacity each. The tanks shall be furnished by the shipbuilder and shall be baffled, have an anti-foaming internal oil return spout, a handhole for clean out and level indicating gages. The outlet shall be supplied with a flap valve, normally screwed and wired open, for convenience in changing engines. The tank shall be located with the normal oil level slightly above the engine oil pump so that it will maintain its prime, but not have sufficient head to flood the engine. There is to be a coarse strainer furnished by the Government located between the tank and the oil pressure pump. Scavenge oil shall be cooled in the heat exchanger furnished by the Government, shall pass through a fine wire wound type strainer, furnished by the Government, between the discharge side of the oil pump and the heat exchanger and then to the oil sump tank. The tank shall be vented to the engine crankcase to keep fumes out of the engine room. There shall be installed by the shipbuilder in the oil" out" line between the lubricating oil cooler and the oil sump tank a bypass thermostat, capable of regulating oil "in" temperature between 130 degrees and 150 degrees F. One bypass thermostat will be furnished by the Government for each main engine. The lubricating oil coolers will be furnished by the Government.

SECTION S47.
PUMPS.

There will be no detached motor-driven pumps.

SECTION S48-1.
GENERAL PIPING SYSTEMS.

This section of the General Specifications for Machinery, issue in effect on date of contract, shall serve as a guide insofar as the component parts and arrangement of the systems are concerned.

**** Line 34: "One electrically driven air horn, equal to or better than Defiance Alloyed Products Co. Defiance, Ohio, Model 100 with 1/8 horsepower motor and Type H18 projector, shall be provided and installed with controls as shown on applicable contract plans for use as a navigation horn, The projector shall be located on top of the chart roam and the motor compressor unit shall be located in the chart room," (Machy. Change No, 2, Sales Order No. N3434) ****

Piping systems necessary for the safe and efficient operation of the vessel shall be installed and shall include the following:

There shall be installed by the shipbuilder between the engine fresh water outlets and the heat exchanger a bypass thermostat, capable of regulating water outlet temperature between 150 degrees and 170 degrees F. at all speeds. One bypass thermostat will be furnished by the Government for each main engine. The heat exchangers required for cooling the fresh water used in the engine cooling system will be furnished by the Government. Arrangement plans for each piping system shall be submitted for approval before installation of the system is undertaken.

All systems under pressure shall be tested to twice the maximum working pressure of the system. The materials of piping, valves, and fittings for circulating water, lubricating oil and fuel oil shall be in accordance with best commercial standards suitable for the service intended or as approved. Fittings and piping of a type resistant to aromatic fuel shall be supplied throughout. Synthetic rubber tubing (Hycar or equal) is acceptable to the Bureau. Aluminum piping shall be kept to an absolute minimum and only Bureau approved fittings shall be used. All piping shall have sufficient supports to prevent vibration. Sufficient take-down joints shall be provided to permit removal and/or replacement of any section. All water, lubricating oil and fuel connections to the engine shall be made with appropriate flexible connections. The bilge drainage will be accomplished by a hand pump as described in the Detail (Hull) Specifications.

SECTION S48-4.
WHISTLES AND SIRENS, APPLICATION AND INSTALLATION.

One horn, type H5a, 24-volt, watertight; in accordance with BuShips Specification 17S11 (INT), or approved commercial i equivalent shall be provided and installed with controls as shown on applicable contract plans for use as a navigation horn. The horn shall be located on top of the chart room.

SECTION S51.
BOILERS.

See section S38-1.

The fuel system shall follow the scheme as shown on contract plan, PT565-S0101M-64159 ****64242**** for the alternates (a) and (b) and contract plan, PT625-S0101M-64162 ****64243**** for alternate (c).

Arrangement plan of the fuel system shall be submitted for approval before installation.

Fuel storage tanks of a total capacity of approximately 3,000 gallons shall be furnished and installed by the shipbuilder as indicated on the contract plans. The fuel storage tanks shall be of a self-sealing type satisfactory to the Bureau.

Fuel from the tanks shall be drawn from each tank through the top and thence to a manifold as shown on the contract plan PT565-S0101M-6459 ****64242**** for the alternate (a) and (b) and contract plan PT625-S0101M-64162 ****64343**** for alternate (c).

Wobble pumps, furnished by the Government, shall be installed in the fuel system as shown on contract plan PT565-S0101M-64159 ****64242**** for alternates (a) and (5) and contract plan PT625-S0101M-64102 ****64243**** for alternate (c).

**** Per BuShips Ltr. 9-11-44 P.T.565-624/S1-5(L51) ****

Each fuel tank shall be fitted with deck filling connections.

Arrangement shall be made for use of portable pump, furnished by the Government, through the filling pipe for pumping water from the bottom of the tanks.

Level indicating gages will be supplied by the boatbuilder. Space will be provided on engine instrument panel for gages.

The fuel to gasoline space heater, section S38-1, shall be drawn from the fuel storage tanks.

SECTION S56-2.
FEED WATER SYSTEMS AND TANKS.

Provision shall be made for replenishing water as needed in fresh water cooling of the main engines. One fresh water expansion tank of about 5 gallons capacity shall be furnished by the shipbuilder for each main engine.

SECTION S58-1.
DISTILLING PLANT.

No distilling plant is to be installed.

SECTION S59-2.
REFRIGERATION PLANT.

For refrigerator, see Detail (Hull) Specifications.

The electrical installation shall be in accordance with the contract plans and these specifications. The electrical tests after installation shall be in accordance with the American Bureau of Shipping Requirements on shipboard, A. I. E. E. Publication No. 45, July 1940, section 45, except that generator load tests are not required. In addition, such tests as may be required by the Supervisor of Shipbuilding, to demonstrate compliance with the characteristics as specified herein, shall be conducted.

A grounding system shall be installed in accordance with Revised Notes on Grounding Radio and electrical equipment in wood hull vessels of the U. S. Navy dated 30 October 1942. (This circular will be furnished by the Bureau upon request.)

No changes or alterations shall be made in Government-furnished equipment without the specific approval of the Bureau in writing for each change or alteration.

SECTION S61-1.
DIRECT CURRENT GENERATORS, SHIP'S SERVICE.

A battery charging direct current generator will be furnished by the Government with each main propulsion engine and shall be suitably installed by the shipbuilder. Each direct current generator will be mounted on a main propulsion engine and will have the following characteristics:

Each direct current generator will be equipped with a carbon pile voltage regulator mounted in a nonwatertight (splashproof) box, together with a current regulator, relays and radio noise filters as shown on plan, BuShips No. 9-S-5620L. ****PT S4103-S1929 & PT S4103-S19130 Per BuShips Ltr 9-11-44 P.T. 565-674/S1-5 (451) **** The voltage age regulators shall be mounted in the engine room in a protected location and where there is a minimum of vibration and shall not be mounted on the engine or any part of the engine support framework. Voltage regulator mountings shall be such as to dampen vibration to a minimum. The machinery contractors installation plans for this equipment require that vibration absorbing mountings be provided.

A direct current ammeter will be furnished for each generator, mounted on the main distribution panel. Ammeters shall indicate the current output of each attached generator.

Two auxiliary generators will be furnished by the Government and shall be properly installed by the shipbuilder in strict accordance with the manufacturer's recommendations supplying this unit. These generators will have the following characteristics:

A carbon pile voltage regulator, reverse current relay, starting relay, ignition coil, thermal instruments, radio noise-filters, switches and other associated equipment mounted in a control panel, in accordance with plan, BuShips No. 9-S-5615-L will be furnished for each auxiliary generator set. This Government furnished equipment necessary for the control and operation of the auxiliary generator set shall be installed by the shipbuilder in accordance with plan, BuShips No. 9-S-5615-L and applicable contract plans.

A direct-current ammeter will be furnished for each 5.5 kilowatt generator which shall be mounted on the main distribution panel. Each ammeter shall indicate the current output of its respective generator.

These generators will be required to operate in parallel with each other but not with the main propulsion engine attached generators.

For tests, see section S60-1.

SECTION S61-3.
MOTOR GENERATORS AND THEIR SHIPBOARD APPLICATION.

The following motor generator set will be furnished by the Government and shall be installed by the shipbuilder.

DC/DC motor generators for radio. See section S67.

The motor voltage for the above motor generator set will be 24-volt, 2-wire, direct current.

SECTION S62-1.
PANELS, ELECTRIC POWER DISTRIBUTION.

A main distribution panel will be furnished by the Government and shall be installed by the shipbuilder, together with such equipment as may be required for the proper operation and control of the vessel's electric plant.

The main distribution panel will be of the enclosed watertight type of construction. The shipbuilder may also mount, together with this panel, the engine instrument panel so as to give appearance of a one unit switchboard. The general design and arrangement of these panels is shown on plan, BuShips No. PT565-S0101E-62167.

This panel will be arranged for the distribution of 24-volt power and lighting and the charging of the ship's service batteries. This panel will have a 24-volt, 2-wire direct current main power bus fed from the three engine generators, the two auxiliary generators and the two ship's service batteries through circuit breakers and switches.

The main distribution panel will contain the following appurtenances together with such other appurtenances as may be required:

All necessary supporting and connecting material required to make a complete installation shall be furnished by the shipbuilder.

The shipbuilder will be notified as to the manufacturer of the panel and shall furnish the panel manufacturer with the following ship design information:

This data shall be forwarded to the panel manufacturer in sufficient time to prevent delay in completion of the panel.

Main engine instrument panel.-A main engine instrument panel will be furnished by the Government and installed by the shipbuilder.

575929-44-9

This panel will contain all necessary engine indicating instruments, and gages, as required for the control and operation of the main propulsion engines.

For detail requirements, see section S41-3.

All necessary supporting and connecting material required to making a complete installation shall be furnished by the shipbuilder.

Bridge engine instrument panel.-A bridge engine instrument panel will be furnished by the Government and installed by the shipbuilder.

This panel shall be installed in a convenient location at the steering station on the bridge.

This panel will be arranged for indicating the engine speed and manifold pressure of each of the three main propulsion engines. The general design and arrangement of this panel will be in accordance with the front view shown on plan, BuShips No. PT565-SO101E-62169.

The panel will be of watertight construction and will have flush' mounted instruments.

All necessary supporting and connecting material required to make a complete installation shall be furnished by the shipbuilder.

Main engine starting and ignition control panel.-This panel will be furnished by the Government and shall be installed by the shipbuilder in a convenient location to the control operators station in the engine room. This panel will be arranged for the ignition control and operation of the main engine starting system and will contain all necessary switches and pushbuttons for starting and controlling the main engine electrical system. This panel will contain the pushbutton for signalling the bridge.

The panel will be of the watertight type of construction and will be in accordance with plan, BuShips No. PT565-S0101E-62170. All necessary and connecting material required to make a complete and satisfactory installation shall be furnished by the shipbuilder.

Nameplates.-All panel-mounted apparatus shall be marked by means of suitable nameplates of laminated phenolic material, either type NDP engraved or type GCP printed (N. D. Specification 17P5) black with white core.

Panel support.-All shapes, angles and other members forming the supporting framework as well as all metal panels and enclosures will be of steel.

Insulating material-Edges, holes and machined surface of phenolic pieces will be given one coat of clear varnish, grade PR, N. D. Specification 17116.

Circuit breakers and switches.-Circuit breakers and switches shall be so mounted that the panel wiring will not be disturbed when the front of the panel is opened or removed.

Painting.-Painting of panels shall be in accordance with Appendix 6 of the General Specifications for Building Vessels of the United States Navy.

Tests.-The electrical tests, after installation, except where specified otherwise herein, shall be in accordance with the American Bureau of Shipping requirements. In addition such tests as may be required by the local Supervisor of Shipbuilding to demonstrate compliance with the characteristics as specified herein, shall be conducted.

Spare parts.-Spare parts for the panels shall be furnished by the Government in accordance with the following list:

Circuit breakers.-One spare for each size and type.

Switches.-One spare for each size and type.

Tools, special.-One complete set, if necessary for proper maintenance.

These spare parts shall be stowed aboard ship in a suitable spare parts box. The spare parts box shall be in accordance with BuShips Specification 42B9(INT). See also section S62-3 and S63-3.

Cable calculations.-Computation of power and lighting cable sizes shall be in accordance with the applicable requirements of section S62-2 of the General Specifications; the drop in voltage in any part of the electrical installation shall not exceed 5 percent.

Painting.-Painting shall be in accordance with the requirements of Appendix 6 of the General Specifications for Building Vessels of the United States Navy.

SECTION S62-2.
ELECTRIC CABLES, ELECTRIC POWER DISTRIBUTION.

Cable classification.-All electrical cable installed on these vessels shall be in accordance with BuShips Specification 15C1 (INT).

All power lighting, interior communication and fire control cables shall be Navy type RI, RIA, or RIB. For cable size above 23000 CM and for multiconductor cable the shipbuilder shall use either Navy type "HFA" or Navy types TRF, TRXF, FJF, FJXF and MHFF cable. Portable or flexible cable shall be Navy oil resistant type COP. Battery jumpers shall be Navy fabric jacket flexible types FJF or FJXF.

Terminal tubes and their packing arrangements shall be in accordance with plan, BuShips No. 9-S-5621-L. Terminal tubes and stuffing tubes shall be so installed as to maintain the watertight integrity of watertight decks, bulkheads, and wiring appliances.

Flexible metallic loom (copper covered) similar to the Breeze or Tite-flex types: for radio shielding purposes, shall be used for enclosing generator and engine electrical instrument leads from the main engines to the voltage regulators. Flexible metallic loom (copper covered) similar to the Breeze or Tite-flex types or aluminum conduit may be used to protect wireways exposed to mechanical damage. The installation of rigid and flexible conduit shall be restricted to those locations where it is required for mechanical protection and shall be the minimum consistent with good practice.

Exposed terminals, clips and lugs shall be adequately protected by means of cotton friction tape and insulating varnish.

Insulating varnish shall conform to N.D. Spec. 52V13d, Grade CA.

SECTION S62-3.
ELECTRIC WIRING EQUIPMENT, ELECTRIC POWER DISTRIBUTION.

Installation requirements.-Electrical fittings and panels shall be of watertight steel construction unless otherwise specified herein. All fittings, panels, and appliances shall be in accordance with Bureau standard plans specified under "List of Electrical Standards" herein. Pull boxes for use with conduit shall be of sheet steel construction.

Three engine connection boxes, one for each main propulsion engine, will be furnished by the Government and installed by the shipbuilder. Each box will be of watertight construction, suitable for connecting the ignition leads, the tachometer leads, and the thermal instrument leads of one main propulsion engine to its respective voltage regulator connection box. These engine connection boxes will be in accordance with plan, BuShips No. 9-S-5618-L.

The contractor shall install a permanent shore power and lighting system.

Connections shall be provided for lights in the engine room, galley and crew's quarters and for the electric range and coffee maker.

The contractor shall also provide a suitable 24-volt shore power system in these vessels. The shore power requirements shall be based on 150 amperes at 24 volts direct current.

Designation and marking.-All boxes and enclosures of electrical fittings shall be marked by means of suitable nameplates of laminated phenolic material, either type NDP engraved or type GCP printed (N. D. Spec. 17PS), black with white letters.

Additional nameplates may be installed in other locations if considered necessary by the Supervisor of Shipbuilding. Lettering shall be at least 1/4 inch high in capital letters.

**** Line 34: "Non-renewable midget or cartridge type fuses shall be installed in accordance with BuShips Spec. 17F2(INT)," (BuShips ltr, 9-11-44-PT565-624/S1-5(451) ****

**** After Line 34: "All I.C. and F.C. circuits requiring an external source of power shall be separately fuesed". (BuShips ltr. 1-30-45 PT565-624/S1-5(451) ****

Painting.-Painting shall be in accordance with the requirements of appendix 6 of the General Specifications for Building Vessels of the United States Navy.

Spare parts.-See section S31-1 herein.

SECTION S62-4.
STORAGE BATTERIES, ELECTRIC POWER DISTRIBUTION.

The shipbuilder shall furnish and install two 24-volt batteries consisting of four Navy standard type 6V-SBMD-175 AH trays each in strict accordance with BuShips Specification 17B4(INT) Batteries, Storage, Portable, and plan, BuShips No. 9-S-4906-L, or commercial batteries of suitable capacity.

Battery boxes.-Boxes for the above batteries shall be furnished and installed by the shipbuilder. Each battery box shall be arranged to accommodate four Navy standard 6V-SBMD-175AH trays. Battery boxes shall be of wood construction. The interior of battery boxes shall be painted with a suitable acid resisting paint. Means shall be provided to secure batteries in place and prevent their dislodgement due to shock.

These boxes shall be so arranged that the individual trays may be readily removed for repairs or replacement.

Charging facilities.-The two ship's service batteries shall be charged in place, from the main power bus on the main distribution panel. Disconnect switches will be provided on this panel for disconnecting each battery from the main power bus.

SECTION S62-5.
ELECTRICAL PROTECTIVE DEVICES, ELECTRIC POWER DISTRIBUTION.

The electrical protection system for protection of power and lighting circuits shall be in accordance with the applicable American Bureau of Shipping requirements.

All feeders emanating from the main distribution panel shall be protected by means of enclosed type circuit breakers, connected in the positive side of the feeder. All power and lighting branch circuits shall be fused.

The enclosed type circuit breakers shall be of the Navy approved type and shall have trip free action.

Tests.-The tests for all electrical protective devices after installation shall be in accordance with the applicable Bureau of Ships Specifications. In addition, such tests as may be required by the local Supervisor of Shipbuilding to demonstrate compliance with the characteristics as specified herein, shall be conducted.

SECTION S62-8.
POWER SYSTEM, ELECTRICAL DISTRIBUTION.

Classification as to installation.-The ship's service installation shall be 24-volt, 2-wire direct current.

General design requirements.-A deck arrangement and an elementary diagram of the power distribution system and the

The shipbuilder shall develop for approval, the required deck arrangements of power wiring showing location of electric auxiliaries and its local wiring on the basis of contract plans.

The shipbuilder shall provide and install feeders and wiring for any electric auxiliaries or interior communication system whether or not shown on contract plans, which may be required to be installed in the vessel and which will suit the final approved capacity of the auxiliaries. Approval of wire sizes and switch sizes on the basis of expected ratings of auxiliaries will not relieve the shipbuilder from installing wiring and switching to suit the final capacities of auxiliaries that may be required by the Bureau concerned.

Outlet for portable bilge and fuel pump.-The shipbuilder shall provide an outlet in a suitable location on deck in accordance with plan, BuShips No. 9-S-4860-L, Alt. 7, 25 ampere D. P., W. T. type B-1S for small boats. The shipbuilder shall also provide a receptacle plug in accordance with plan, BuShips No. 9-S-4859-L, Alt. 6 type B-1.

SECTION S63-3.
SHIPBOARD APPLICATIONS OF DIRECT CURRENT MOTORS.

Direct current motors shall be satisfactory for the service application. The local Supervisor of Shipbuilding shall authorize such tests as he deems necessary to demonstrate the suitability of the service application proposed. The local Supervisor of Shipbuilding may also authorize such tests as he deems necessary to demonstrate to his satisfaction that the motors proposed will function satisfactorily under all service applications.

All motors shall have suitable filters mounted on the motor frame and properly connected and installed to minimize or eliminate radio noises.

Spare parts.-See section S31-1 herein.

SECTION S64-1.
LIGHTING SYSTEM DISTRIBUTION.

Classes of circuits.-One lighting system, designated as "ship's service" shall be installed.

Ship's service lighting system.-Applicable contract plans show the general arrangement of the lighting system. These contract plans are for the guidance and information of the shipbuilder and are subject to additions, modifications and developments as may be required to suit structural and other arrangements as finally approved for this vessel.

The shipbuilder shall develop for approval the required working wiring deck plans, on the basis of contract plans.

Cable designations shall be in accordance with contract plans. Feeders shall be 24-volt direct current, fed from power bus established on the main distribution panel.

Two portable lights, commercial watertight type or type DD, W. T. plan, BuShips No. 9-S-5392-L and adapters shall be furnished and installed. These adapters, similar to Perko Cat. 670 or equal, shall be provided for adapting the medium screw base of socket, plan, BuShips No. 9-S-4836-L, for bayonet candelabra, double contact base lamp, 24-28 volt, 15 c. p., similar to Navy type TS-102 (Mazda No. 1692). These portable lights shall each be equipped with 25 feet of portable cord, DCOP-3, and receptacle plug to fit the receptacles provided on the lighting system of vessel.

Outlets for portable equipment shall be installed in location and number as shown on contract plans.

Flashlights in accordance with BuShips Specification 17F7, in number as required by the Master Allowance List, shall be provided (furnished by the Government).

Four hand lanterns, type J-1S, with mounting brackets, in accordance with plan, BuShips No. 9-S-5311-L shall be installed as shown on contract plans.

Arrangement of running, signal and anchor lights shall conform to type plan, BuShips No. 9000-S6405-73103.

The following running, signal and anchor lights shall be installed:

These running, anchor and signal lights shall be controlled from a bridge control panel located on the bridge as shown on contract plans.

This bridge control panel in accordance with plan, BuShips No. 9000-S6401-73165 shall be designed to incorporate the following.

Lighting system control.-Lighting system control shall be in accordance with contract plans.

Detail distribution requirements.-The lighting fixtures shall be so installed as to give the most illumination over mess tables,. desks and in the proximity of mirrors.

A door switch shall be installed in accordance with plan, BuShips No. 9-S-5589-L as shown on contract plan.

SECTION S64-2.
LIGHTING SYSTEM, FIXTURES.

Lamps.-Lamps for use in white general lighting fixtures, red signal lighting fixture and portable lights shall be bayonet candelabra double contact base, 24-28 volt., 15 c. p., similar to Navy Type TS-102 (Mazda No. 1692).

Lamps for use in 110 volt shore power system shall be medium screw base, 50 watt, 115 volt, similar to Navy Type TR-5.

Regular fixtures.-Lighting fixtures shall be in accordance with BuShips standard plan specified under list of "Electrical Standards" herein.

SECTION S65.
INTERIOR COMMUNICATION.

All shipbuilders furnished equipment for I. C. and F. C. circuits shall conform with Bureau plan, insofar as applicable, as specified under list of electrical standards herein. No interior communication equipment listed in these specifications shall be used by the shipbuilder for any purpose during the construction of the vessel prior to 3 months before the delivery date of the vessel except for necessary tests to determine the reliability of the equipment. The main runs of interior communication and fire control system cables shall, in general, follow the cable runs of the lighting and power installation.

The following string type telephone circuit shall be installed:

One jackbox and one telephone shall be installed at each station.

The Government (Bureau of Ships) will supply the telephones 14 (amplified type) and blast helmets (2 large, 5 medium.) The Government (Bureau of Ships) will also supply one spare telephone for each vessel.

SECTION S65-3.
VOICE TUBES.

One voice tube shall be installed from bridge (cockpit) to Radar control station. No calls.

SECTION S65-4.
ELECTRICAL SIGNAL AND INDICATING SYSTEMS.

Circuit A-Officer's Call Bell System.-Install pushbutton at bridge and type H5a horn (BuShips Specification 17S11 (INT)), in crew's quarters. (See sec. S64-1.)

Circuit E-Sound Powered Telephone Call Bell System.- Install as indicated in section S65-1 with pushbuttons at bridge and in engine room, type 115a horn in parallel with red lighting fixture in engine room, and buzzer in bridge. (See sec. S64-1.)

**** H3 Horn BuShips Spec 751/1 (Int) Except wound for 24 volt- (BuShips Ltr. 9-11-44 PT565-671/S15(415) Mach. Chg. No 2 Sales O.N 3434 ****

Circuit K-Engine Revolution Indicator System.-Install transmitter at each engine with indicator in engine room and on bridge. Equipment will be furnished with engines.

Circuit W-Whistle Operating System.-Install pushbutton bridge to operate navigation horn. (See secs. S48-4 and S64-1.)

575929-44-10

Provide and install mechanical rudder angle indicator on bridge.

Provide and install a mechanical engine order telegraph (without reply) system between the bridge and the engine room. A combined transmitter shall be installed on the bridge with an indicator for each engine. The system shall provide for the following orders "Ahead," "Neutral," and "Back." The equipment shall be of the "Teleflex type" or of a type approved by the Bureau.

SECTION S66-1.
SEARCHLIGHTS, SHIPBOARD APPLICATION, Dated 1 November 1933.

One 8-inch incandescent searchlight will be furnished by the Government and shall be installed and connected by the contractor for signalling use. The power for the 8-inch searchlight shall be supplied from the ships' service normal 24-volt supply.

All necessary supporting and connecting material required to make a complete and satisfactory installation shall be furnished by the shipbuilder.

Applicable paragraphs of section S66-1.

S66-1-h-2(a).-(Except that "8-inch" shall be substituted for "12 inch".)

S66-1-i. Tests.
S66-1-j. Spare parts, tools and storage.-

SECTION S67.
RADIO INSTALLATION.

Radio communication equipment will be furnished by the government and shall be installed and connected for operation by the shipbuilder in accordance with plans approved by the Bureau. The equipment will consist of radio transmitters, receivers, whip antennas and antenna insulators. All cable and wire shall be furnished by the shipbuilder and installed in accordance with plans approved by the Bureau. Power feeders, outlets, and fittings shall be installed as required.

The Bureau of Ships will furnish standard type plans for the radio installation. The shipbuilder shall make detailed plans based on type plans. Copies of these plans should be forwarded to the Bureau for final approval. The installation shall be made in accordance with the approved detail plans.

A naval radio engineer will be available, if considered necessary, for consultation in regard to the preparation of detailed plans and also for making adjustment to and tuning the equipment after installation has been completed by the shipbuilder.

***** Page 73, line 40 to page 74, line 8 This system shall provide means for electrical firing of torpedo launching racks. from a control panel remote from the racks. Circuit shall be energized from ships 24 volt supply. Wiring is shown on Bureau of Ships Plan 37104-607107. (BuShips ltr. 9-11-44, PT565-624/S1-5(451). Hull Chg. A-5-(1) S.O. N3458 *****

SECTION S67-5.
SEARCH RADAR INSTALLATION (Circuit 2R-ER).

Search radar equipments will be supplied by the Government (Bureau of Ships). The main RF units comprising the classified components such as the transmitter, receiver and indicator will be installed by the boatbuilder. The installation shall be accomplished only by shipbuilder's employees especially trained and authorized to install the classified components of Radar Equipment under direct supervision of the Supervisor of Shipbuilding.

The shipbuilder shall allocate space required for equipment, furnish and install equipment foundations, cables, and other incidental wiring materials as required to provide a complete and satisfactory installation including any special features the Bureau of Ships may elect to furnish in accordance with radar type allowance and pertinent equipment data as contained in the Radar Installation Plan effective at time of issue of these specifications.

The services of a naval radio engineer will be made available for consultation if desired.

SECTION S67-6.
I. F. F. EQUIPMENT.

I. F. F. equipment will be supplied by the Government (Bureau of Ships).

The general requirements for search radar equipment also apply to I. F. F. equipment.

SECTION S69-3.
PORTABLE ELECTRICAL INSTRUMENTS.

Portable electrical instruments shall be supplied in accordance with the following list:

Suitable provision shall be made for the satisfactory stowage of the equipment aboard ship.

SECTION S71-1.
ELECTRICAL FIRE CONTROL, SIGNAL, AND INDICATING SYSTEMS.

Circuit 6PA-Torpedo firing system.-This system shall provide means for firing torpedoes from a contact maker for each tube

**** After Line 30: "Circuit 9PA rocket firing system - This circuit shall provide means for electrical firing of the rockets from the bridge. Power to the system shall be 24 volts from ship's power (Bridge control panel). (BuShips ltr 1-30-45, PT565-624/S1-5(451) ****

located at the bridge. Contact makers shall be type M-XV-S, plan, BuShips No. 9-S-4835-L. Circuit shall be energized from a source having a voltage up to 20 volts or a 6-volt, 100 AH storage battery. A snap switch, type TT-S, plan BuShips No. 9-S-4720-L, shall be provided at the contact makers for deenergizing the circuit from the source of supply. This circuit shall not be provided for torpedo tubes which are fired by air under control of a hydraulic system or for torpedo launching racks.

Circuit VE-Depth charge release signal system.-This system shall consist of an audible signal 24-volt direct current, similar to type B-4 bell (BuShips Specification 17S11 (INT)) at the depth charge racks energized by a pushbutton located in the bridge. Supply shall be 24 volts direct current. (See sec. S64-1.)

Circuit 5U-Light projectile machine gun cease firing signal.- This system shall consist of a 24-volt direct current horn similar to Type H5a horn (BuShips Spec. 17S11 (INT)) at the aft 20-mm. gun energized from the bridge. Supply shall be 24-volt direct current. Navigation horn will serve as an audible signal for forward 20-mm. and 50-caliber machine guns. (See sec. S64-1.)

Circuit GA- Torpedo course data transmission system. This system shall provide means for setting the vessel on a torpedo collision course. Inputs shall be provided from the lux gate compass and radar to a Course Control Unit in the chart house. Inputs shall be provided from the course control unit to a "Right-Left" helm indicator mounted in the dashboard on the bridge and to a Director Sight Coupling Unit on the bridge. Above instruments will be Government (Bureau of Ordnance) furnished. Supply will be 24 volt alternating current, 400 cycles from the fluxgate compass inverter or from a special inverter furnished by the Government.

SECTION S91-1.
SHOP EQUIPMENT.

There shall be supplied and installed by the shipbuilder:

INDEX