353.4
June 13, 1940
SUBJECT: Narrative Report, Firing of Battery Harris, 16-inch
TO: Commanding Officer, Harbor Defenses of Sandy Hook, Fort Hancock,
NJ.
1. In compliance with instructions in letter of the War Department dated
December 27, 1939, the Harbor Defenses of Sandy Hook were instructed to
fire a target practice at Battery Harris, Fort Tilden, New York (16-inch)
during the current fiscal year. The Commanding Officer, Harbor Defenses
of Sandy Hook, designated Battery B, 7th Coast Artillery to move to Fort
Tilden, New York during the month of March and to be supplemented by
available men at Fort Tilden, New York.
2. The practice was planned for the month of May, 1940. In the
meantime, all steps were taken to put the equipment in readiness for the
practice. This battery had not been fired since 1935, during which time
the battery has been on a caretaking status. During the calender (sic)
year 1939, the ordnance machinist and all available men have worked on
the electrical equipment of this
battery to make it function. The time and energy devoted to preparing
these guns for firing was reflected in the operation during firing. At
no time was the firing delayed due to material failure. One shot was
delayed a fraction of a minute due to hang fire. Again a few T.I.'s were
lost due to primer failures. This constituted the failure of the guns.
Much time was spent making the speed
gears function properly. It will be necessary to remove the rammer speed
gear from Gun #1 for replacement.
3. The weather conditions have been such that on the days a boat was
available, it was impossible to get a service course to track. It was
not until the day of the practice that our observers has an opportunity
to track a target at 30,000 yards, at which range we intended to open
fire. The attached visibility chart obtained from the local Coast Guard
station indicates that for the period May 11th to May 27th inclusive, at
no time was the visibility sufficient for the
service course.
4. It was necessary to concentrate our efforts into three widely
separated days to get off the sub-caliber firing. It was decided that
the first day following May 28th with the necessary visibility the
practice would be held. The afternoon of May 28th, about 3:30, the area
cleared and the visibility appeared to be better than it had been for
several weeks. The next morning, the 29th, the boat was ordered out to
the course and, although the sky was overcast, the visibility seemed to
be improving. The plan was to track the target across the field of fire
once, return to the starting point and fire on the second course. This
plan was followed, but by the time we received a clearance from the
Safety Officer, the target was well on its way down the course. This,
and several delays for the safety officers, accounts for the short range
on the first course.
5. The location of the points of observation for the safety officers'
detail were such that it complicated the work involved, thereby causing
delay. After the first round, a telephone line used by the Assistant
Safety Officer went out, and fire was held up until he could get a
clearance over another line.
6. The first record shot of No. 1 gun put the T.I. bell at No. 2 gun
out of commission, and necessitated the firing of the first two rounds
from no. 2 gun with a stop watch.
Just as the third round of record fire was to be fired from No. 1 gun, it
was reported from Long Beach, the left flank station, that a haze
obscured the target. Firing was suspended several bells. When the Long
Beach station was back on target, the haze had drifted across the Arverne
Tower line of sight. The facts were reported and cease firing was given.
By this time the target was nearing the end of the course. The tug was
ordered back to the starting point. By
about 4:30 p.m., it appeared to be clearing in the East, but the target
was still not visible from one station. We were determined to get in
another course before dark, having 6 rounds left, two of which were in
the guns.
The tug was ordered to run a parallel course 2000 yards closer to the
battery. The target was finally picked up by all observers and spotters.
The command to "Commence Towing" was given, and fire was opened up on
the second course. At no time during the firing could a meteorological
message above the third zone be obtained.
7. Fire Control: In order to get away from the busy channel
between Long Island and New Jersey, steps were taken to establish a fire
area that would be the least affected by shipping.
For ranges up to 30,000 yards the practicability of the 100-foot towers
located in the vicinity of Battery Harris is questioned. There being no
tower available beyond the Arverne Tower, it was decided to improvise an
observation station at Long Beach upon the structure of the Long Beach
Gas Tank. A height of 200 feet was available at this location. A Model
1910 azimuth instrument
was mounted on an improvised pedestal. This was known as B3, the left
flank station, 22,374 yards from the D.P. The 100-foot tower at Arverne
is known as B2, and was used as the right flank station. The Arverne
Tower is 12,042 yards from the D.P. This tower was also used as
S2.
For the course chosen, the maximum range from either observing station to
the target was to be 20,000 yards. This was made possible by the fact
that the two stations and the D.P. were almost in line, in an East-West
direction. The possibility of seeing the target from the 100-foot tower
at Fort tilden was so slight that arrangements were made to use the South
tower of the Marine Parkway Bridge, which is just outside the
reservation, for the Battery Commander's station. This station has a
height of over 200 feet, and with good visibility, the range
possibilities are excellent. This station was used for S1 as well. On
the days that tracking at long range would have been possible, the bridge
tower, the Arverne tower, and the gas tank station were intervisible.
8. The Coast and Geodetic Survey party during the local survey provided
us with the geographical locations of our station sites, and the
Artillery Engineer in turn produced the coordinates for them. When these
were finally obtained, a brass platen was made up by the local ordnance
machinist for this baseline.
9. Analysis: On looking over the available records of the
previous firing of this battery, which consisted of a velocity test
followed by a practice of 9 rounds fired with full charge, there appeared
to be insufficient evidence to base an initial adjustment for a
7/8-charge.
Incidentally, the range discs had to graduated for 7/8 charge. The
clinometer was read by Lieutenant Cordes, and the range disc markings
were checked by the ordnance machinist.
The date of the firing was overcast to the extent that a meteorological
message beyond the third zone was not obtainable.
The first ranging shot was lost by the flank spotter. The aerial
observer, due to certain limitations of ceiling, called the deviation
3000 yards. A down correction was ordered to bring the next shot in the
glass. The succeeding three shots were well grouped. The fist shot was
considered erratic, so the adjustment was based on three shots.
The record firing started, and after one shot from each gun the Safety
Officer called the field of fire unsafe. After a delay of three minutes
, fire was resumed. One more shot from each gun was fired. The results
were: #1 gun, both short; #2 gun, both over at least 400 yards. At this
time a haze came up over the water in the line of sight of the S3
observer, and the firing was therefore help up until the two stations
could resume tracking. The S2 observer lost the target,
the order to cease fire was given, and a long delay ensued waiting for
the field of fire to clear. During this long delay, much thought was
given to the shots that had been fired.
The two shots from gun #2 were together and considerably over #1 gun.
This deliberation resulted in an arbitrary down correction of 240 yards
for #2 gun, which was applied on the range percentage corrector. This
correction brought the two guns reasonably close together. A small up
correction was made, which resulted in a hit on the first shot of the
second course by #1 gun.
An up correction, if applied on the last two shots, probably would have
resulted in another hit.
The errors were comparatively small, considering the scale used on this
plotting board, 800 yards to the inch.
In order to get the first shot and the corrections on the graphical
analysis, it was necessary to put two sheets together.
The score is low, due in part to the range component based on a short
range, which was due to conditions beyond the control of the operating
personnel. See visibility chart for period preceding date of practice.
It is believed that an accurate meteorological message would have
resulted in more accuracy with the ranging shots.
It appears to me that the powder pressures should have been higher. See
chart of pressure plug measurements attached. In view of the fact that
the expected powder pressure for full charge is 38,000 pounds, it seems
that for 7/8 charge the pressure should exceed 28,000 pounds. Prior to
this firing, the area burnt appears to be larger than before.
Considerable copper remains in the bore. The only means of removing this
appears to be mechanical.
PAUL A. JACCARD,
Captain, 7th CA.,
Commanding.
2 Incls.
Notes:
T.I. Bell = The Time Interval bell used to signal the observers at the
fire control stations to stop tracking the target so that the readers can
read the azimuth to target at the same time. This allows the crew at the
plotting board to plot the position of the enemy ship (or practice target
in this case) at 30 second intervals. After several positions are
computed, a predicted future position of the target , corrected for wind,
temperature, etc..., can be plotted.