5101. Safety precautions.-Rigid adherence to safety orders is an absolute necessity in motor torpedo boat machinery operation and any laxness in this regard cannot be tolerated. The amount and high volatility of the fuel carried and the relative large quantity of explosives concentrated on board, makes the motor torpedo boat extremely hazardous with regard to fire and explosion. The high operating speeds and unstability of the hull give rise to dangers to personnel working in machinery spaces. Careful and diligent compliance with all safety rules will minimize the hazards and prevent casualties.
5102. Conservation of machinery.-Every effort must be exerted to conserve machinery on board in order to have a reserve of power for emergencies. All machinery in a motor torpedo boat has been made as light as possible for efficient operation and the hours of use available on each unit are relatively short before an overhaul is necessary. Most overhauls and repairs cannot be made while underway and therefore the boat must remain inactive while machinery is removed, replaced, or repaired. In this connection, a common violation is the excessive use of clutches and engines in making a landing alongside a dock. A good landing is one that causes a minimum of damage to the boat. To jockey back and forth in order to make a four-point landing, at the expense of the engines and a dozen shifts on the reverse gears, is definitely a damaging operation. MTB's are very light and can readily be hauled in by hand once the dock is approached closely enough to get a line or two across. Another violation is running the engines unnecessarily at excessive speeds, which tends to shorten their life.
5103. Auxiliary generators, batteries and wiring.-These units may properly be considered the "life blood" of the boat. They
supply the energy for lighting, operating the radio, firing torpedoes and heating food. The importance of their conservation and proper care, in order to be available for emergencies, is obvious. Hence never shorten the life of the auxiliary generator by running it when other sources of power are available. If in port, batteries should be removed from the boat and charged from tender or shore facilities rather than by charging from auxiliary generators. Tender or shore current should be used whenever possible, for lighting or heating food. Careful inspections and tests of all electric wiring should be made at frequent and periodic intervals.
5104. Machinery inspections and operation.-The machinery installed in MTB's is extremely delicate, of precision construction, and must be operated accordingly. Instructions in machinery operating manuals and instruction books will be followed. It has been necessary to sacrifice certain factors of ruggedness in order to conserve in weight. Frequent and periodic routine inspections must be rigidly carried out on all machinery, in accordance with existing instruction and operating manuals, to discover any deficiencies that subsequent operation will aggravate into major or minor casualties. Care and upkeep that would prove adequate for the satisfactory operation of a heavy duty, slow-moving marine engine is far from adequate on a MTB. Personnel must pay careful attention to temperatures, oil pressures, etc., in order to prevent damage to machinery.
5105. Repairs.-It will often be necessary to effect repairs of an emergency nature that fall in the "baling wire" category. However, these repairs should be replaced with permanent ones at the first opportunity, in order to restore the original installation. All repairs should be effected in an approved manner and in accordance with existing machinery instruction books.
5106. Spares.-The amount and types of spares to be carried on board should be limited to those needed for repairs which can be made while under way. This will reduce the weight of the boat and keep the spares in better condition.
5107. Safety orders and machinery operating instructions.-These will be posted in conspicuous places near the machinery units to which they apply, and frequently read to the crews.
5108. Cleanliness.-Cleanliness of engineering spaces and machinery is a requisite of good engineering practice and in motor torpedo boats must be strictly enforced. Clean machinery and machinery spaces reduce the danger of fire and minimizes the
possibility of foreign material reaching the vital parts of the machinery.
CHAPTER 2. COMMUNICATIONS
Doctrine and Practice
5201. Communications in motor torpedo boats are difficult even under good conditions due to the unstable platform, exposure of personnel to seas and weather, and the limitations of the facilities available on board.
5202. Facilities.-The following facilities are available for communications:
(1) Radio telephone and telegraph with limited output range and power supply.
(2) Signal flags.
(3) Semaphore flags.
(4) M. P. (multi-purpose) signal light.
(5) Blinker tube.
(7) Arm signals.
(8) Verys pistols.
(9) Code and cipher publications similar to those carried by aircraft.
(10) Radio direction finder.
5203. Radio transmissions.-In view of the necessity for radio silence during wartime or the transmissions of radio messages in code, use of the radio will normally be restricted on motor torpedo boats and confined to very urgent messages. However, during the progress of a motor torpedo boat attack on the enemy, or if being attacked by the enemy, full use of the radio should be made, if it will add to the effectiveness of the attack or counterattack.
5204. Visual communications.-Visual communications should be used whenever possible. During daytime operations when motor torpedo boats are in small compact formations, hand and flag signals will normally be the primary method of communicating between boats. At night, when the security of position will not be disclosed, blinker tube or signal light will be necessary. If light signals cannot safely be used, boats will close and communicate by word of mouth.
5205. Encoded messages.-When encoded radio communications are permitted and the necessity for communications between boats is urgent, it will be found expeditious to arrange certain
code words in advance to denote phrases appropriate to the particular mission on which to be engaged. This will preclude use and probable compromise of, official code publications which ordinarily cannot be conveniently carried or used aboard motor torpedo boats. For communicating with other units of the fleet, the aircraft signal book and contact report pads are adequate and should be carried on board.
5206. Authenticators.-Radio personnel should develop the habit of recognizing the voices of their contemporaries on other boats, thus eventually eliminating the need for authenticators when orders are transmitted by radio from one boat to other boats.
5207. Conservation of power.-(a) The necessity for conserving power when operating in motor torpedo boats and the importance of keeping radio equipment in an excellent state of repair cannot be too greatly emphasized. Emergencies may occur requiring continuous operation of the radio for long periods. Also circumstances may arise where the state of readiness of the radio may determine the destruction of one's own forces, an enemy force or the destruction of an individual boat and crew.
(b) Maintenance and periodic overhaul of material should be made in accordance with the prescribed check off lists and weekly reports.
(c) Effective safety measures should be continually employed to prevent the following:
(1) Shorting of wires and sparking of loose connections.
(2) Injury to personnel from dangerous voltages in antenna and transmitter.
(3) Creation of explosive hydrogen gases in storage batteries due to improper ventilation.
(4) Static electricity and consequent sparking as a result of broken bonding.
(d) Radio direction finder equipment should be calibrated as soon as the boats are received and calibration curves should be kept posted in the immediate vicinity of the equipment.
5208. Standard procedure.-(a) Standard procedure is absolutely essential and must be adhered to by personnel operating the radio. Some of the more important details of proper procedure are given below. A complete guide is given in Naval Communication Instructions.
(b) In wartime encoded call signs are assigned to and used by each boat to preserve secrecy of identity. The examples below
give the regular calls for simplicity: Assume the PT 1 wishes to call the PT 2 and order it to return to base.
Step 1-2 from 1, 2 from 1, answer.
Step 2-1 from 2, go ahead.
Step 3-2 from 1, return to base, acknowledged.
Step 4-1 from 2, wilco.
(c) The above steps illustrate the following basic principles:
Step 1-The addressee's call is always given first.
Answer is used when trying to establish contact with another
Step 2-Go ahead is used when contact is established and when either the addressee or the sender is ready for the other party to "come back".
Step 3-Acknowledge is standard phraseology for requesting acknowledgment.
Step 4-Wilco means "I will comply" and is used by a boat on receiving instructions from a senior boat to carry out an order. The use of wilco should not be confused with that of the word roger. Roger is used merely to acknowledge that a message is received; it does not imply the intention to comply.
5209. Operation.-Efficient radio communication requires constant effort to eliminate the following practices:
(a) The use of unauthorized procedure which permits the enemy to associate types of craft with the operating peculiarities of the personnel.
(b) Unnecessary use of the radio. This is the most common form of bad communication practice. It is dangerous in that it permits radio direction finding and consequent compromise of security of position.
(c) Excessive test counts. Test counts should be held to an absolute minimum.
(d) Operation of the radio by inadequately indoctrinated personnel.
5210. Personnel.-All members of a MTB crew must be qualified in standing a radio watch. Each man must have an operating understanding of the radio equipment, know the Morse Code, understand the effective call sign, and Recognition and Emergency Identification System. Each man must know MTB communications procedure as well as the basic principles of sound communication practice set forth in Communications Instructions. The importance of training and disciplining operating
personnel in the developing of sound communication habits cannot be overemphasized. In the last analysis the standard of radio communication efficiency will largely depend on the intelligence of the personnel and therefore selection of only the best qualified is of paramount importance.
5211. Recognition and identification.-(a) Because of the similarity of the general appearance between MTB's and submarines, MTB's are not infrequently mistaken for enemy submarines by friendly surface vessels and aircraft. It is, therefore, of the utmost importance that MTB personnel be trained to use maximum speed in identifying themselves. Emergency recognition signals and Verys pistols should always be kept at hand to avoid a moment's delay when needed.
(b) The communication officer on MTB's should have made out daily, the following lists for all MTB's in the squadron:
Four days recognition and emergency identification signals.
No boat captain should get underway without having these lists aboard and he should be personally responsible for turning the list in when his boat returns to base.
5212. Confidential publications.-Confidential publications carried on board MTB's should be carried in a locked W. T. case which will readily sink when thrown overboard, in case the boat is captured or destroyed. These cases should be turned in to commanding officer upon return to base.
5213. Security.-The highly confidential nature of certain military characteristics of motor torpedo boats must be guarded against compromise. New personnel, personnel under training and civilian contractors working in an official capacity with motor torpedo boats must be thoroughly instructed regarding the importance of preserving the inviolability of confidential information regarding the size, seaworthiness, cruising radius, speed, armament, armor and operations of motor torpedo boats.