The writer was recently ordered as a member of a trial board on one of our new cruisers, and remembering his hazy ideas concerning what his duties might embrace, believes that a discussion based on knowledge gained by him in the performance of this duty might prove interesting as well as instructive to officers who have not as yet had any such experience.
This discussion is not a description of any actual proceedings, but merely how, in light of my experience, I think that trial boards for our new cruisers should be organized, and how the trial should be conducted.
As thousands of dollars depend upon the result of these trials, and much rivalry and competition exist between contractors, it becomes very important that the results should be not only accurately determined, but that the methods of obtaining them should be as nearly identical in all cases as circumstances will permit. For this reason it would seem that, were a general order issued concerning the organization and methods governing the procedure of such boards, it would tend to uniformity of reports, and be of great assistance to the board in conducting the trials.
The precept accompanying the orders calls attention to the most important points to be determined, leaving the method of determining them to the discretion of the board. This may seem at first thought a very simple thing to do, but my experience convinced me that the method of conducting the trial of a cruiser should be well considered and planned beforehand.
It is important that the board meet and organize at the earliest practicable date, and organization and proceedings should be based on the rules governing "Courts of Inquiry."
The orders and precept should be read and carefully discussed, so that no matters of detail will be left in doubt. All officers that have been connected with the construction or fitting out of the vessel to be tried, as well as the officers ordered to duty in anticipation of going in commission with her, should be invited to appear before the board and give the members the benefit of their knowledge and views concerning the vessel. The contractors, also, should be invited to appear, or send a representative for the same purpose.
Committees should then be appointed, and the senior members instructed that the report of their committees would be expected before the vessel-was ready for her trial trip, in order that any serious defect or departure from contract, etc., could be known before her trial trip. It is possible, but not probable, that something might exist which would render it impossible to accept the vessel, even though she proved successful as to speed. It would probably be convenient to appoint four committees:
1. To determine whether the vessel is sufficiently strong to carry armament, ammunition and all necessary stores. This committee should take charge of, and carry on tests for strength and manoeuvring qualities, as hereinafter described.
2. To determine whether the hull and fittings are strong and well built and in accordance with contract, plans, drawings and specifications, and to duly authorize changes in the same.
3. To determine whether the machinery and appurtenances are strong, etc. (At least one member of this committee should be in the engine-rooms during the trial.)
4. To keep a record of all expenses connected with the trial trip.
Committees Nos. 2 and 3 will find their duties very comprehensive and requiring much attention. It involves, first, a close examination of contract, plans, drawings and specifications, and an overhauling of all correspondence relative to changes. The superintending naval constructor should furnish these committees with copies of the specifications, with all authorized changes entered, and with these for guides, the committees must find out, as far as practicable by investigation and inspection, whether or not the vessel is strong and well built and in accordance with contract, etc, and duly authorized changes.
Committee No. 4 should, as soon as possible, commence enquiries concerning the expenses connected with the trial trip, and to do this should require the contractors to furnish them with a pay-roll of vessel as ready for trial. They should ascertain how many persons are to go on the trial trip, and agree with contractors on a rate per diem for such persons; and no others should be permitted on the vessel during the trip. With the pay-roll, quantity and price of coal, list and prices of all necessary stores, rates per diem for subsistence, allowance for bedding, linen, crockery, etc., there would be no subsequent trouble about the expenses to be allowed. The reports of the sub-committees having been reviewed and discussed, the board is ready to proceed with the trial trip.
If practicable, the vessels to take current observations should be in or near their stations at least one day before the trial is to commence. A day's practice in observing the currents would be beneficial. One should be anchored exactly on the range at one end of the course, and at a previously determined distance from the shore signal (about 100 yards inside of the line of the course), and the other similarly on the range at the other end of the course. Two vessels will be enough, as the steam launches of these vessels could be anchored on the line joining the two vessels, each ten miles distant from its own vessel. I see no reason why these launches could not be anchored in any water likely to be found on any trial course, and in any weather favorable for a trial trip. If the water was very deep, a wire and light grapnel could be used. The vessels and launches should make as much black smoke as possible, so as to serve as a guide for the vessel on trial to steer by during the run. If practicable, signals should be erected on shore at convenient distances sufficiently close and distinct for triangulating from the vessel during the trial run. The "range signals" should be particularly high and well defined. An accurate projection of the course, shore line and signals, on a good working scale, should be at hand. Three independent sets of observers should be detailed (each set consisting of two members), and stationed forward, amidships and aft. One observer of each set should observe when the vessel crosses the range lines, and the other to observe and record the times. There should also be one observer to keep an accurate record of the courses steered by standard com pass, direction, force of wind, sea, etc. If the course is staked out along the shore by signals, as suggested, there should be two observers with sextants to angle on the signals, and so keep the course the vessel was making graphically plotted. The commander of the vessel should be cautioned to make a long enough sweep after crossing the second range to enable him to come on the line as near as possible where he crossed it. This is important, particularly on account of current effects. Accurate observations of wind and sea should be recorded. Each set of observers' record times of crossing ranges from their stations and the mean of the three time-intervals (corrected for chronometer rates) should be taken as the correct time-interval. Chronometers should be compared before and after trial.
As soon as the trial is over the board should meet to consider data. The length of the course has presumably been determined and officially reported to the board. The average strength and direction of current should have been signaled as the vessel on trial passed the current observers, so that a close approximation for current allowance could be made immediately after the run. It is a question whether or not allowance should be made for poor steering. Where the increase in the length of the course, due to poor steering, can be accurately determined, I am of the opinion that it should be allowed, as it does not seem just that the vessel should be credited with a less speed than she is known to have made. With care, and the course marked by the current observing vessels, there should be no allowance necessary on account of broken course; but as a broken course may be made, the question of allowance should be decided by the Department and embraced in the "General Instructions."
Correction for Current
a, b, c, d = strength of current per hour (reduced to direction of course), observed at stations during run of vessel with current.
a' b', c', d', = same during run of vessel against current.
As soon as the speed has been approximately determined, the representative of the contractors should be called in and informed of the speed made, and asked whether or not he was satisfied with the trial. If so, he should then be informed of the nature of the tests required, and requested to be ready for them at as early a date as possible.
In the meantime the fire and steam pumps should be tested, as well as the water-tight doors, valves, battle-hatches, etc In fact, everything on the vessel which can be put to a practical test.
Being ready for steering gear and engine tests, the vessel should be put to sea, and the strength of hull, fittings, etc., be determined by inspection while under way, the following tests being considered desirable, not only to determine the strength of hull and fittings, but to demonstrate the manoeuvring qualities of vessels.
First Set of Tests—(Steering Wheels, Helm, etc.)
A. With steam wheel in pilot-house. Both engines going ahead full speed (knots). Order "Hard-a-starboard." Time to put helm hard over (number of degrees). Time to complete half-circle. Time to complete full circle.
B. Ship still turning with starboard helm (full speed). Order "Steady," "Hard-a-port." Time to put helm hard over (number of degrees), during which the vessel fell off ° to port, and started to go to starboard in seconds.
C. Steam wheel in conning tower. Going ahead with both engines full speed (knots). Order "Hard-a-port" and "Back starboard engine." Time to put helm hard over (number of degrees). Time for engine to commence backing. Time to complete half-circle. Time to complete full circle.
D. Steam wheel on quarterdeck. Going ahead full speed with both engines (knots). Order "Hard-a-starboard," "Back port engine." Time to put helm hard over (number of degrees). Time for engine to commence backing. Time to complete half-circle. Time to complete full circle.
E. Hand wheel on quarterdeck (number of men on wheel). Same as A, with time to change from steam to hand gear.
F. Steam wheel in steering-room. Same as A, with time to change from hand to steam gear.
G. Hand wheel in steering-room same as E.
Second Set of Tests
A. Going ahead full speed with both engines (knots). Signal "Back." Engines commence to back. Vessel stopped (time), in a distance (number of yards), (distance to be ascertained by a chip-log with a very light line, which cannot possibly interfere with working of screws if caught). Engines backing full speed (time), (revolutions).
B. Ship backing full speed. Signal "Ahead full speed." Engines commence going ahead. Ship stopped (time). Ship going ahead (time). Engine going ahead full speed (time), (revolutions).
The trial of the vessel being over, the board should meet to discuss the report, the proceedings being governed by the rules for " Courts of Inquiry." The written report should give a full record of proceedings, and all data obtained, with conclusion of board. A list of work still remaining incompleted by contractors should be appended, and also the probable time necessary to complete the vessel ready to be accepted by the Government.
When the latter fact has been reported to the Department by the contractors, the board should be ordered to convene again to report whether or not the vessel was in every particular ready for acceptance.
The work of the board being completed, they adjourn sine die to await action of convening authority.