USS Providence Historical Prospective

Cromwell O. Smith Jr. RdM 3/c
(Radarman Third Class )
May 15, 1945 to June 27, 1946

                The following prospective are my thoughts and opinions of the mission of the USS Providence during its early days.

                While the Providence was on the ways and being put into commission the war in the Pacific was raging.   The Kamakazi had made its appearance and proved to be very effective against naval forces during the battle for Okinawa.  The US Navy had established a line of radar pickets comprised of Destroyers between Okinawa and the mainland of Japan to detect and counter the Kamakazis.  The average life of a DD on the picket line was about 78 minutes.  For this reason the Navy had decided to establish a picket line of cruisers for the invasion of Japan comprised of specially equipped Cleveland class light cruisers and Atlanta-Oakland class of AAA cruisers.  The USS Providence was one of the chosen ones.

                Because air attack was much more probably than surface attack a special off shoot of General Quarters (GQ) was developed and designated “Air Defense”.  When Air Defense was sounded all crews designated Air Defense crews were given priority to move to their stations before GQ was sounded.  The flow of traffic in either event was “Forward starboard, Aft port, Up starboard, Down port.

                (a) Main battery 12 – 6”/47 in four triple turrets (not much use for air defense)
                (b) AA Battery:
                                1. Six 5”/38 twin mounts
                                2. Four radar controlled quad Bofors 40mm mounts on the com deck between the stacks
                                3. Six additional dual Bofors 40mm mounts on the main deck, manual control
                                4. Ten single mount Orlikon 20mm along the main deck

                (a) Air Search
                                (1) SK-2 Long Range, Low Frequency
                                (2) SP-1 Medium range, medium frequency with height finding capability
                (b) Surface Search
                                SG-1 (Later developed into the SPS-10)
                © Fire Control
                                (1) MK-8 Main battery fire control
                                (2) Mk12/Mk22 Five inch dual mount control
                (3)MK-28 Forty mm MK 37 director control

Radar was not nearly so sophisticated as it is today.  Perhaps a brief description of the radars is appropriate.

The SK-2 was an improvement over the SK-1 in that it had a large parabolic antenna as compared to the SK-2 which had a similar but larger “bedspring” similar to the previous SC series of radars.  It operated at a higher frequency than the SK-1 at 215 MHz carrier.  It was still primitive in that the final output was a pair of triode oscillators and pulse length was determined by the “grid leak” method.

The operator sat at the control console and using the PPI scope and a manual cursor, detected and tracked any air targets.  The lobe pattern of the antenna caused the antenna patterns to have holes in its detection pattern.

The ship’s A/C were used to “calibrate” these hole patterns and create “fade” charts which could provide elementary and sometimes accurate altitude information on incoming targets.

The SP was a primitive form of height finder and required two operators.  It operated in the “C” band and had a parabolic antenna that was controlled in both azimuth and elevation manually by an operator.  It had a “wobbler” that resulted in a conical scan of the main beam.

The conscan allowed the operator to center the target in the beam so that the elevation angle could be read off a dial indicator.  The left had operator had an “A” scope and an  R” scope.  A “pipper” or range step  on the A scope was placed in the vicinity of the desired target.  An abbreviated A scope (which represented only a small part of the A scope) appeared on the R scope.  When the operator put the target in the “ditch” on the R scope, the right hand operator had a special three inch diameter scope.  With no target in the “ditch” the beam was a spot.  When the range operator placed the target in the R scope ditch, wings appeared on the dot.

The pointer/trainer operator endeavored to keep the spot with the wings on the center crops hairs of the special scope. A third operator could then read the elevation angle and using a special chart could determine the altitude of the A/C.  Crude but more effective than the “fade chart” method of altitude determination.

The SG was primarily a surface search radar operating in the “C” band which hd an “A” scope and a PPI for detecting and tracking surface targets. The primary operators console was located in:”Combat Aft” which was a compartment on the 03 level just behind the #5 Five inch mount.

The MK 8 was for the main battery and being surface oriented only provided range and bearing.

The MK12/MK22 was a combination where the MK 12 provide range and bearing in conjunction with the MK 22 with its nodding antenna provided elevation for the dual 5”/38’s.

The MK28 had a parabolic antenna equipped and allowed the operator to manually track the target in range for the 40mm quad mount while the pointer and trainer tracked the A/C manually.

In addition to the primary radar scopes available to the primary operator, there were auxiliary, remote indicators. 

The VF had two scopes, a PPI and a “B” scope.  The B scope presented a selected partial magnified view of the PPI.  Range rand up and down and azimuth ran right and left.   By using a hand crank, the user could place a cursor on the PPI over the target and run the range ring out and get a close view of the target, allowing the operator to get a range and bearing while the antenna continued to rotate.

There were VF’s in CIC, in Flag Plot and on the bridge.  Because RADAR was new and some of the older crew member had difficulty interpreting the radar returns, radar operators were stationed on the bridge and in flag plot to operate the remote indicators.

In CIC there were two 24” PPI’s a VG and a VG-1.  The VG-1 was the left handed version of the VG.  Generally speaking these displayed the SK-2 PPI so that the CIC officers could view the radar picture directly.

Combat Information Center

                CIC was the primary control center for all surface and air search radar information.  It was located on the main deck forward of the athwart ship weather deck passage way and lay between the Captain’s cabin on the starboard side and the Admiral’s cabin on the port side.
                Against the forward bulk head were two large plastic see through plotting boards behind which stood two plotters who, using yellow grease pencils, plotted target data provided by the radar operators. Aft of these were the VG1 and the VG1, remote displays on which the operators plotted data which the CIC officers could view and evaluate the data.

On the port side further aft were the DRT (Ded Reakoning Tracer), which received data from the pitometer log and the gyro compass and drove a lighted bug showing the ship’s position and travel.  A scale agreeing with the scale of the selected chart was selected and the bug would follow the ship’s motion.
On the starboard side to the end of the VG’s was the VF which CIC officers could use to measure range and bearing to the desired targets without having to stop the rotating radar antenna.

Further along the bulk head were two radio operators copying any radio traffic.

On the rear bulkhead were the main operator’s consoles for the SK and the SP radars.  The SK console was on the starboard side facing aft.  The operator using a manual cursor and range rings could read range and bearing of targets and pass the info along.

On the port side facing aft were the two SP operators tracking the designated target.  Ther CIC officers roamed the CIC managing the operations. Over each operators console was a thermite bomb container which contained a bomb that the operator was used to disable the radar set in the event of abandoning ship.

The VF and the VG’s could display any of the search radar data by being switch through the IC control room.
The VF on the bridge were operated by radar operators and brought about some special training for those who were bridge qualified.  The Captain decreed that anyone of the bridge should be able to operate as a helmsman or a lee helmsman; so we were trained to do so.      




Cromwell O. Smith Jr. RdM 3/c
(Radarman Third Class )

May 15, 1945 to June 27, 1946