by the Office of NOAA Corps Operations
Puget Sound Maritime Historical Society
History of Ship PATHFINDER
The following historical account of the Ship PATHFINDER is reproduced
through the kindness of the Puget Sound Maritime Historical Society
(PSMHS), a non-profit organization devoted to capturing the MARITIME
history of the United States Pacific Northwest. The Coast and Geodetic
Survey conducted pioneering surveys in the Puget Sound region in the
1850's and has home-ported ships in the Seattle area since the early
1900's. This account of the PATHFINDER was published in the official
publication of the PSMHS, SEACHEST Vol. 16.3, pp. 103-113, March
of this article is Rear Admiral Harold J. Seaborg, NOAA (Ret.), who
first was associated with the PATHFINDER in 1946 while refitting it
after it was returned to the Coast and Geodetic Survey by the Navy.
Subsequently, he served as Commanding Officer of the PATHFINDER in
1963 and 1964. Rear Admiral Seaborg entered on duty in 1929 with the
C&GS and commanded five C&GS vessels during his career. He
served as the first Director of the Pacific Marine Center in Seattle,
Washington, from where he retired in 1967.
PATHFINDER - THE CHRONICLE OF A SURVEY SHIP
BY REAR ADMIRAL HAROLD J. SEABORG, NOAA (Ret.)
The U.S. Coast and Geodetic Survey Ship PATHFINDER was built by the
Lake Washington Shipyards in accordance with specifications and contract
plans prepared in the office of the Coast and Geodetic Survey Headquarters,
Washington, D.C. The awarded contract, dated September 25, 1940, was
for the sum of $1,267,000. Subsequent changes in the specifications
reduced the cost of the completed vessel to $1,265,448, a rather small
cost reduction, but a saving when compared to large overruns of some
of the present day similar contracts. The contract period was 720
days, from October 4, 1940, to September 23, 1942. The vessel was
completed on August 31, 1942, ahead of time, but the urgency of the
war effort may have contributed to the earlier completion. The USC&GSS
EXPLORER had been build by the same shipyard a year earlier, but PATHFINDER
was increased in size and had other modifications.
PATHFINDER's keel was laid at Houghton, Washington, on February 20,
1941, and the ship was launched on January 11, 1942. The ships sponsor
was Miss Eleanor Roosevelt Boettiger, granddaughter of President Franklin
Delano Roosevelt. Soon after launching, a request was channeled through
the Department of Commerce by the Navy for the transfer of the ship
for wartime use, the Coast and Geodetic Survey being an agency under
Commerce. The transfer was approved and armament and other naval features
were installed concurrently with the completion of the vessel under
the prime contract.
This survey ship was an all steel vessel, 229 feet in overall length,
breadth of 39 feet, depth of 23 feet, and with a loaded mean draft
of 15 feet. She was a single screw, with double reduction gear, steam
turbine powered vessel developing 2000 shaft horsepower with a full
load displacement of 1900 tons. Steam was provided by two watertube
boilers. Auxiliaries were two turbine driven main generators and a
diesel generator for emergency use. She developed full power when
reversing. Her maximum speed was 15 knots with a cruising range of
9000 miles and with a fuel oil capacity of 110,000 gallons.
Her main and upper
decks were the length of the ship. The lower deck was forward and abaft
the machinery spaces, and the superstructure deck went aft about three-quarters
of the ship's length from the bow. The bridge deck with the compass
deck atop were placed forward of midships on the superstructure deck.
A small poop deck was raised some 3 feet above the upper deck and carried
the double wheel auxiliary steering station. All outside steel plated
decks were covered with calked wooden planking. She carried two masts
with funnel between and her hull was divided by eight watertight bulkheads,
some of which had watertight doors. In accordance with the original
specifications four 30 foot diesel powered wood sounding launches, two
24 foot gasoline powered whaleboats and several 16 foot skiffs were
installed. In the beginning these small boats served as the life saving
equipment in addition to several life floats.
PATHFINDER was designed
to accommodate 19 officers and 68 crew. However, the conversion involved
extensive changes in the arrangements as the crew was more than doubled.
Another addition was the installation of a chart reproduction plant
with a capacity of 5000 copies of small charts per hour. This would
provide for the issuance of nautical charts directly in the field upon
completion of hydrographic surveys.
The most modern
of special instruments and equiment for hydrographic surveying and navigation
were installed. This included echo-sounding fathometers, electric powered
sounding machines for wire casts and various rangefinders. Also installed
was a Sperry gyrocompass system complete with master compass, steering
and bearing repeaters and gyropilot for steering sounding lines. The
magnetic compass was standard U.S. Navy equipment. Radio equipment included
several code radio transmitters, a ship-to-shore radio telephone and
a radio direction finder. In addition, there was radio telephone equipment
designed for use by detached parties from the ship. A two way local
speaker communication between the pilothouse and various parts of the
ship became part of the equipment. Also installed was a fire control
system operated from the bridge deck area to automatically close watertight
doors and activate carbon dioxide (CO2) in the various closed
compartments. An electric submerged log installed inside the hull was
provided for measuring distances the ship traveled when underway.
On August 31, 1942,
PATHFINDER was placed in commission as a full fledged Navy fleet survey
ship designated USS PATHFINDER (AGS-1). She now was ready for wartime
duty. After a short shakedown cruise in Puget Sound, PATHFINDER sailed
for San Francisco, arriving September 20. Upon completion of minor repairs,
stores and provisions were loaded and the ship steamed out of San Francisco
Bay on November 10, 1942, setting course for Pearl Harbor. PATHFINDER
departed Pearl Harbor on November 28 on the first of her two long wartime
cruises. It should be noted that during the time when the ship was with
the Navy seven experienced C&GS officers were aboard initially in
a transfer status. This immediately brought a wealth of survey knowledge
to a ship on a special mission. Later the number of C&GS officers
The U.S. long range
war plan in the southwest Pacific was to break the Japanese hold on
the New Guinea-New Britain-Solomon Island arc. This was to be the area
of PATHFINDER's operation for nearly two years. Her mission was to provide
charts for the ever-expanding Allied amphibious operations; surveying
uncharted harbors, lonely stretches of coastline and inland channels.
It was necessary to send small parties ashore in the furtherance of
these surveys, sometimes going into enemy held territory.
cruise took her to the Solomons and neighboring island groups. While
working close to the front lines, the ship, although essentially non-combatant,
experienced some fifty bombing raids and on April 7, 1943, her anti-aircraft
gunners shot down two Japanese planes. In August, 1943 and in March,
1944, she was at Sydney, Australia for short periods of liberty and
relaxation. She surveyed as far north as New Guinea before departing
the war area for home at the end of September, 1944. PATHINDER ended
her first cruise at Alameda, California, on October 21, 1944.
back to the war zone for her second cruise on December 18, 1944. By
this time our forces had swept northward and the scene of conflict had
shifted to the Philippine Islands area. After several way point stops,
Guam was reached on February 4, 1945. While in this area, Pathfinder
Reef, some 350 miles northwest of Guam, was discovered and duly charted.
On March 28, 1945, she was attacked by two enemy planes while surveying
along the eastern coast of Luzon in the Philippines but once again escaped
damage. She was not so lucky on May 6, 1945, when along the Japanese
side of Okinawa a Japanese Kamikaze plane crashed into PATHFINDER's
after gun platform killing one man and setting fire to the ship, which
was quickly brought under control. The mainmast was clipped off during
this engagement. Upon contact with the ship the plane slid off the stern
into the sea.
During the final
stages of the conflict in the Okinawa area, PATHFINDER was at general
quarters 170 times. Japan's wartime radio broadcaster, Tokyo Rose, reported
the ship sunk at least on six different occasions. The ship continued
her charting activities in support of the advancing Allied Forces. On
August 15 the long-awaited word "Cease all offensive operations" was
indeed welcome news. PATHFINDER's last survey duty during World War
II was among the Japanese home islands in coordination with the Allied
occupation. She departed Yokosuka Naval Base, Tokyo Bay on December
5, 1945, arriving at Seattle, Washington on December 24, and was placed
out of commission on January 31, 1946. For her excellent work in helping
to survey the road to Tokyo, she was awarded two campaign or battle
stars and received the written commendations of Admirals Nimitz, Kinkaid
of necessary repairs and restoration for peacetime survey duty, PATHFINDER
was returned to the Commerce Department and on August 23, 1946, was
recommissioned as a unit of the Coast and Geodetic Survey ship fleet.
A shakedown cruise to Bristol Bay, Alaska, was made soon thereafter
and then she returned to Seattle in the early fall to close out a shortened
1946 field season. She later was to be designated Ocean Survey Ship
30 and carry the legend OSS 30 on her bow. She was berthed at the south
end of Lake Union at leased facilities along with other units of the
During the field
seasons 1947 through 1950, PATHFINDER continued surveys in the Bristol
Bay area. Previous charts were largely based on hydrography extended
beyond the visual range of the shoreline by dead reckoning lines. Dead
reckoning at its best is far from exact, as too many variables such
as currents and imperfect steering can only be estimated. However, such
areas as Nushagak and Kvichak Bays and Ports Heiden and Moller were
covered by modern type surveys. Shoran equipment, a special type of
radar, was used extensively in the hydrographic surveys of Bristol Bay.
Fuel, provisions and other supplies were obtained at Dutch Harbor, the
field base of operations when working the Bristol Bay area.
Shoran (Short Range
Navigation) gives quite accurate determination of position. Developed
during W.W.II to control the position of aircraft in flight, Shoran
was adapted by the Coast and Geodetic Survey in 1945 for the positioning
of sounding vessels. Shortly thereafter Shoran became the standard control
system for hydrographic surveys ranging as far as 100 miles offshore
under favorable conditions. The position of a sounding vessel is obtained
by measuring the elapsed time between a transmitted radio pulse and
the return signal from two fixed stations, usually ashore. The two times
are converted to distances for plotting purposes. The line of sight
limitation was reduced by placing, when possible, shore stations on
high land points. This equipment worked very well in such an area as
Bristol Bay where weather conditions often precluded visual sights upon
shore signals for location of the sounding vessel, either ship or launch.
Shoran required trained electronic technicians to keep the equipment
in proper adjustment and calibration. Survey operations in the Bristol
Bay area were generally hampered by the large tidal range and extensive
shoal water areas. However, Shoran has accuracy limitations when within
several miles of the land stations. Thus, the close to shore hydrography
was usually accomplished by launches, traditionally using sextant fixes
upon established hydrographic signals along the shoreline. During hydrographic
sounding it was necessary to have a series of tide stations or gages
in operation which were referenced to an established standard station
somewhere in the general working area to establish the tidal datum plane.
The first use of
aerial photographs for map and chart making began before W.W.II. By
1949 the Coast and Geodetic Survey had developed its own program of
preparing shoreline manuscripts based on aerial photography. When possible,
manuscripts were prepared at Headquarters, using special plotting equipment
to provide shoreline and other topographic features ahead of operations
in the field. In Alaska, in some instances, only preliminary manuscripts
could be furnished because of insufficient information. The field parties
would then have to inspect photographs and apply the missing information
by other means. The general use of manuscripts signaled the end of topography
by hand-drawn plane table methods. In the ensuing years, PATHFINDER
used these manuscripts whenever available.
surveys and manuscripts, and in turn hydrography, are controlled by
a basic scheme of triangulation. These schemes consist of a series of
marked land stations whose positions are precisely determined by instrumentation.
Special geodetic parties working as independent units provide this basic
control. However, ship parties are usually required to extend or breakdown
the previously established primary control to provide a greater density
When working on
a combined project where ship and launches were programmed to do hydrography,
a survey ship such as PATHFINDER would anchor in a protected area as
close to the general working area as possible. Launch and other small
boat parties would then be dispatched to work ashore or close into shore.
The ship might then weigh anchor and do hydrography at the outer limits
of the project, returning to pick up the small boat parties.
During the 1951
field season three survey ships were engaged in a project to tie established
geodetic control points along the eatern shore of the Bering Sea to
the off-lying islands. PATHFINDER coordinated the project, assisted
by EXPLORER and PIONEER. The concept was to measure distances between
mainland stations and stations on the off-lying islands by means of
Shoran and a second electronic system known as Electronic Position Indicator
(EPI). With a beginning in 1944, select Coast Survey personnel devised
the EPI system which combined the best features of Shoran and Loran.
Loran (Long Range Navigation) was another electronic system used in
navigation and developed during W.W.II. The EPI system had a greater
range than Shoran as the transmitted pulses followed the curvature of
the earth rather than line of sight. The use of EPI, as in Shoran, requires
the placing of shore stations at previously determined land points.
The usable range is something like 250 miles, but under favorable conditions
can be used to 500 miles.
Bering Sea islands such as St. Lawrence and the Pribilofs had been surveyed
using independent datums derived from astronomic positions. The 1951
work was to establish a common datum with the mainland to the outer
reaches of the Bering Sea. The lines to be measured ranged between 100
and 500 miles and these lengths would be involved in the triangulation
computations. The successful completion of this project provided for
future homogeneous hydrographic surveys for an improved charting program.
PATHFINDER was able
to utilize this improved control during the field seasons of 1952 through
1954 in the completion of hydrographic surveys in the general area of
the Pribilof Islands. Economically, the field season in this area began
about May 1st and ended sometime in September. During the 1954 season
Mount Shishaldin on the Alaska Peninsula was observed in eruption at
a distance of eighty miles. Hydrographic surveys were made along the
north coast of the Alaska Peninsula during the seasons of 1955 through
1958. In 1959 the ship's working area shifted to Cook Inlet and this
continued into 1960. Part of 1960 was devoted to the occupation of oceanographic
stations in the northern Pacific wherein the properties of sea water
were recorded and studied by means of sea water samples. Bottom samples
were also obtained.
was assigned a new project in the Hawaiian Islands in 1962. Her primary
mission was to update nautical charts by a program of new hydrographic
surveys. Because of much better weather conditions the working season
began earlier in the year. Departure from Seattle was in early February
for her working base in Honolulu. Upon completion of a special survey
at Christmas Island in mid-Pacific she began a systematic resurvey of
close-in areas around Maui, Molokai and Lanai. Prior offshore surveys
were considered adequate. A return to Seattle was made in June followed
by a second cruise to the Hawaiian Islands. Tracklines or sounding lines
were run between the west coast, usually Cape Flattery, and the Islands
on every trip across the Pacific and return. Loran A and C provided
the prime control on these long line surveys, with adequate checks by
astronomic sights. This program provided additional charting information
in open ocean areas. The ship averaged some 10,000 to 15,000 nautical
miles each year in deep-sea hydrography. This program also applied to
The Hawaiian Island
surveys continued the first half of the 1963 field season. In early
July PATHFINDER departed Seattle to conduct a cable route survey between
Guam and the east coast of Luzon Island, the Philippines. This survey
was at the request of International Telephone and Telegraph Company.
A replenishment stop was made at Midway Island and later at Manila Harbor
and the Naval Base at Subic Bay. This was the first and only return
of PATHFINDER to the western Pacific, an area of her W.W.II exploits.
While in Manila Harbor several pre-arranged meetings were held with
the top officers of the Philippine Coast and Geodetic Survey. Philippine
personnel had been in a training status for a number of years and when
the country was granted its independence in 1946 the Philippine Survey
cam into being. The new survey had several of its own vessels as the
small U.S. Coast Survey fleet in the Philippines was lost during W.W.II.
Upon completion of the cable route survey, the ship returned to her
basic project in the Hawaiian Islands, arriving in Seattle in early
October. She was berthed for the first time at the newly completed ship
base on the eastern shore of Lake Union. For the remainder of her service
time the Pacific Marine Center Ship Base was to be her home, along with
other Coast and Geodetic Survey vessels, later to become the NOAA fleet.
The Hawaiian Islands
work continued in 1964 but was interrupted by the need for surveys following
the March 28 Alaska earthquake. The ship arrived at Kodiak by direct
passage on April 8 and, upon taking provisions and fuel, departed for
Seward in Resurrection Bay. A desolate scene greeted PATHFINDER. Huge
sections of the built-up waterfront had slid into the Bay, leaving a
tangled mass of railroad rails and pier sections hanging over the water's
edge. Inshore, overturned railroad cars, fuel storage tanks, trucks
and automobiles were a jumbled mess. PATHFINDER found anchorage in the
upper bay. Sufficient triangulation control was recovered for the topographic
plane table surveys for shoreline and signals and in turn the hydrographic
surveys. Aerial photographs were not available and sextant angles were
taken to position the launches and ship during hydrography. It was necessary
to fall back on these time honored methods of surveying when the more
modern approach was not possible. The survey of upper Resurrection Bay
was completed by mid-April and in early June a temporary chart was issued
showing considerable bottom changes in this earthquake stricken area.
surveyed the principal shipping lanes in Cook Inlet north to Anchorage
and also made a detailed survey of the Anchorage waterfront. These surveys
proved no significant charting changes in these areas. Local hydrographic
surveys at Homer and Seldovia revealed no bottom changes, but shoreline
piers and structures had been damaged. For the remainder of the 1964
season a new project, the re-survey of Kamishak Bay in lower Cook Inlet,
was begun. This area required more detailed surveys at a larger scale.
This work was continued in 1965.
During the 1965
season, when working at the entrance to Cook Inlet, PATHFINDER personnel
became interested in the Alaska Christian School, an orphanage some
10 miles out of Homer. The ship began making a twice yearly call at
Homer to bring the children down to the ship for a tour and a dessert
treat in the wardroom. She indeed became a "foster mother," donating
fresh fruit, candy, toys and clothing to the orphanage.
At the beginning
of the 1965 season, two of the original launches were replaced with
modern-type Navy equipment. These 30 foot launches had more space forward
to accommodate increased instrumentation needed when using electronic
control. Later, the remaining two original launches were replaced. Original
wooden whaleboats were also replaced with a modern type of reinforced
plastic design. Also, 1965 saw the first use of a data logger system,
wherein hydrographic surveying elements are logged into a punched paper
tape for use in plotting surveys on an automatic plotter housed ahsore
at Pacific Marine Center. This system was to save many man hours of
tedious hand plotting.
The first half of
the 1966 field season found PATHFINDER resuming her hydrographic project
in the Hawaiian Islands. By early June the ship was at Homer, Kachemak
Bay, Alaska, extending triangulation control in that area to check any
relative movement of the land mass resulting from the 1964 Alaska earthquake.
No significant changes were found. The main project in Kamishak Bay
was then resumed and continued for the remainder of the season.
During the winter
lay-up period, personnel of the Survey Fleet would be engaged in multiple
activities. Deck, engine-room and electronic departments effected maintenance
and minor repairs. Junior Commissioned Officers replotted hydrographic
surveys to produce what was commonly known as the "smooth sheet." Also,
triangulation, tide, current and other survey records were prepared
in systematic form for transmission to Headquarters. The Operations
Officer was responsible for the completion of all survey records.
A board composed
of the Executive Officer, Chief Bosun and Chief Engineer prepared in
draft form any necessary repair and maintenance items which the ship's
complement was unable to perform. Usually the Commanding Officer would
then prepare the specifications for outside ship repairs for submission
to Headquarters for approval and funding. Invitation to bid would then
be submitted to various shipyards, with delivery of the ship to the
successful bidder for haulout the first part of the new year. During
all of this time a program of the taking of accumulated annual leave
for all hands was followed.
However, with the
advent of Pacific Marine Center and Ship Base in 1964, a staff of qualified
personnel ashore began to assist in and coordinate ship repairs and,
to some extent, the processing of survey records. When funding was available
PATHFINDER and other ships were thus able to spend more time in the
During the early
months of 1967 PATHFINDER was engaged in a combined project along the
coast of Southern California. Loran B, a navigation and ship position
electronic control system, was installed and used on this project with
a great deal of success. Operations shifted to Kamishak Bay during May
and continued as the main Alaska project. Some work was also done at
Montague and Middleton Islands. In June a temporary platform was built
over the poop deck for the use of a leased helicopter. This was to provide
ship-to-shore transportation for a shoreline triangulation project in
Shelikof Strait. This was the last season that Shoran was used. The
equipment was old and obsolete, and replacement units and parts were
not readily available.
PATHFINDER did not
make an early cruise in the 1968 season. She arrived at Kodiak in early
May and her main effort was again in Kamishak Bay with some work in
Kodiak Harbor. On her return from the Cook Inlet area she began a project
in Clarence Strait in S.E. Alaska.
A new electronic
control system for ship and launch hydrography, Raydist DR-S, was used
by PATHFINDER, replacing Shoran. Raydist, prodeuced commercially, was
adapted and refined by the Coast Survey, providing more accurate and
reliable positioning of vessels in open water. This equipment has a
range in excess of 200 nautical miles and required two shore based stations
which were, however, automatic in operation and only required an occasional
visit by trained personnel. Portable units were develped for launch
use and several sounding units could operate simultaneously.
The 1969 season
followed the pattern of 1968, but in early 1970 PATHFINDER returned
to the Hawaiian Islands before resuming her main projects in Cook Inlet
and Clarence Strait. In 1971 more of the same in Cook Inlet and S.E.
Alaska. This was to be her last season, as she was deactivated on September
10, 1971, upon return to Seattle. PATHFINDER had put in nearly 30 years
of faithful service but her age and a tight budget precluded any further
work as a survey ship.
All usable equipment
and instruments, including radio and electronic survey gear, spare parts
and supplies of all types, were removed and transferred to other ship
units or stored for future use. Deactivation was completed December
23, 1971. PATHFINDER's career ended when the General Auto Wrecking Co.
of Ballard purchased the stripped ship, and she was scrapped at their
yard in 1972.
seemed to be a happy ship. After W.W.II many of her crew, enjoying a
special Civil Service status as shipboard personnel with seagoing rates,
remained on the ship year after year. Her last Chief Bosun spent some
15-odd years aboard. Some of the personnel in the Engineering, Radio-Electronic
and Steward Departments had similar years of duty. There was more movement
with the Commissioned Officers of the Survey, who usually were assigned
for two year tour of duty as ship and survey officers, thus wearing
two hats. The commanding officer was also the Chief of Party.
of her service have been salvaged and preserved in the Seattle area.
The double wheel auxiliary steering stand once located on the poop deck
and the standard magnetic compass and binnacle are now on display at
the Pacific Marine Center headquarters on Lake Union. In the lobby of
Capitan's Table restaurant, Elliott Avenue in Seattle, mounted on two
panels are some twenty assorted steam, air, lube oil and water guages
from the engine room of PATHFINDER. The author completed a scale model
of the ship in April 1983, which is presently on display in the Marine
Room of Edmonds Museum, Edmonds-South Snohomish County Historical Society,
During the last
years of her gallant service, PATHFINDER found herself under new direction.
In July 1965, the Coast and Geodetic Survey merged with the U.S. Weather
Bureau to become Environmental Science Services Administration (ESSA)
still within Commerce. Then in October 1971, the National Oceanic and
Atmospheric Administration (NOAA) was formed bringing together the Bureau
of Commercial Fisheries and ESSA along with several other government
agencies. The legend of the 90 year old Coast and Geodetic Survey was
to be no more. Her functions were taken over by the National Ocean Survey
under NOAA. For those who served on her and knew her well, PATHFINDER
will always remain a Coast and Geodetic Survey Ship.
Rear Admiral Seaborg, then a Lieutenant, served on a small C&GS
staff when PATHFINDER was returned by Navy in 1946. Also, he served
as Commanding Officer in 1963 and 1964.
Special Publication No. 143, Hydrographic Manual, Revised 1942 Edition.
2. Office of Naval Records and History, History of USS PATHFINDER (AGS-1),
Revised 7 June 1950.
3. The Journal, C&GS, June 1953, No. 5.
4. U.S.C.&G.S. Publication 20-2, Hydrographic Manual, 1960 Edition.
5. NOAA Publication, January 1972 issue.
6. Marine Digest, May 26, 1973; May 1, 1982.
7. Various Annual Reports, Coast & Geodetic Survey.
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