History Op-20-G-4E/ late 1945

This document from National Archives, Record Group 457, Box 1419.

History of Section OP-20-G-4E




The history of the section that eventually became OP-20-G-4E is shown here in progressive block diagrams. The time of the diagrams is picked to show sample months during the several stages of development The appendix includes:

1. Detailed history of section up to time of expansion to Include other equipment than Bombe.

2. Detailed subsection history from the time of expansion until end of report.

3. List of Library file numbers for project reports.



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This summary will concern itself primarily with:

(a) The history of a group of technical Personnel at The Naval Communications Annex. This group was Assigned various designations during the period 1943 to 1945. The designation on V-J Day was Op-20-G-4E.

(b) The history of related events leading to the formation of this group.

Throughout this description the rank of various officers and enlisted personnel referred to will be the rank that person had at the time referred to.

The Naval Communications Branch of Op-20 (Op-20-G) during the early part of 1942 had need of technical assistance for the development and construction of certain specialized equipment. A general development contract was placed with the National Cash Register Company Dayton, Ohio. Ralph I. Meader (later Lt. Comdr. Meader) from the Bureau of Ships acted as liaison between Op-20-G and N.C.R. Joseph R. Desch of the National Cash Register Company electrical laboratory acted as Chief Engineer.

During the summer of 1942, for the purpose of expediting the Naval work, Lt. Comdr. Meader was designated Officer-in-Charge of the Naval Computing Machine Laboratory, Dayton, Ohio, an activity for directing the N.C.R. development contract, and providing liaison between the Navy and N.C.R.

During the fall of 1942, work was started on pilot models of a special analytical machine termed the Bombe. Development work on this project was entirely under the supervision of N.C.R. civilians and Lt. Comdr. Meader until February 1943, when Lt. (j.g.) W. A. Dayger and Lt. (j.g.) E. Staples reported to Dayton to assist Lt. Comdr. Meader.

It was the intent of Lt. Comdr. Meader to utilize Naval personnel to assist in the testing and construction of the Bombe units. The final installation of the Bombes was to consist of about 100 units. Personnel used for the testing and construction were to maintain and operate this final installation. To effect this during the period from February to August 1, 1943 the Naval complement at Dayton was built up through a special procurement program for technical personnel.

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The remainder of this history will concern Itself with a group which eventually was designated OP-20-G-4E at the Naval Communications Annex and was formed from a nucleus of technical personnel originally stationed at the Naval Computing Machine Laboratory. In general, the function of Op-20-G-4E has been the maintenance of special analytical equipment, the engineering of small changes on such equipment, setting up of new machines, re-building of old equipment, and execution of small development projects. Further, a small machine shop and stockroom for useof Annex personnel has been a part of this group

As stated previously, the nucleus of this group started at the Naval Computing Machine Laboratory. These people were primarily from the group concerned with maintaining it pilot Installation at U.S.N.C.M.L. and those people who inspected and tested the machines as they came off the production line.

The maintenance program began about May of 1943 when certain officers obtained under a special procurement program reported to Dayton. These were:

Ens. Orem 10 May 1943
Lt. (j.g.) Palmer about 20 May 1943
Lt. (j.g.) Hemmer about 1 June 1943
Ens. Noble about 5 June 1943
Lt. (J.g.) Blakely 10 June 1943
Lt Summers 10 June 1943
Lt. (j.g.) Faust about 5 July 1943
Lt. (j g.) Roenning 10 July 1943
Ens. French about 15 July 1943
Lt. (j.g.) Reed about 25 July 1943
Ens. Hayes 10 August 1943

About 15 July 1943, Lt. Comdr. Meader, and Joseph Desch designated Lt.(J.g.) Blakely as supervisor of maintenance on a pilot installation of the Bombe equipment at Dayton. Lt. (J.g.) Howard was supervisor of the operations on this pilot installation.

Initially, the pilot installation was of two Bombe units known as “Adam” and “Eve”. Simultaneously with this initial installation, construction was underway on the final model of the Bombe equipment.

The initial maintenance group consisted of Lt. (j.g.) Hemmer, Lt. (j.g.) Palmer, Lt. Summers and Lt. (j.g.) Roenning with about 12 enlisted men.


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The test and construction group of the final models consisted of Lt. (j.g.) Reed. Ens. Orem, Ens. Noble, a number of N.C.R.civilians including Robert Mumma, Vincent Gulden, Larry Kilhiefe (sic), Ralph Bruce and a number of enlisted men.

The officer and enlisted personnel assigned to both test and maintenance were Interchanged as much as possible in test and maintenance work. The intent of this was for the officers and men while on test to become thoroughly familiar with the equipment and while on maintenance to become familiar with the system of maintenance and routine checks which had been instituted.

About August 1, it became evident that shipment of Bombes to Washington would begin early In September. Lt. (j.g.) Blakely assigned Lt. (J.g.) Hemmer the duty of organizing a parts stockroom for the Washington organization. Lt. Hemmer and Lt. (j.g.) Blakely both made trips to Washington at this time; Lt. (j.g.) Hemmer remaining for several weeks. Parts lists, tool lists and stock cabinet designs were made and the necessary items ordered and shipped to Washington. About 1 September 1943, four final model machines. N-530, were shipped. Lt. (j.g.) Reed, Lt. (jg.) Palmer, Klein, RT 2c , Jarrell, S1c, M. Cook, MM 2c went as maintenance personnel.

On 15 September, Lt. (.j.g.) Blakely, Lt. Roenning, Lt. Staples Lt. Summers, Lt. (j.g.) Hemmer, Ens. French, Ens. Hayes, Ens. Noble, Ens. Orem and a group of about 50 enlisted personnel reported to Washington. The entire group was organized into a subsection known as Op-20-GM-7 under Commander Engstrom as Op-20-GM. This orqanlzation consisted of the following personnel:


Lt (j.g.) Robert T. Blakely Lt. (j.g.) James E. Reed
Lt. (j.g.) George A. Hemmer Lt. (j.g.) George W. Roenning
Lt. Edmund B. Staples Lt. Llewelyn L. B. Summers
Ens. Robert E. French Ens. Edwin G. Hayes
Ens. David L. Noble En Sidney P. Orem


Ens. Mary E. McCabe Ens. Marguerite T. Thomas
Ens. E. McNichol


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Edward D. Sohn, S 1c William D. Chambers, S 1c
Kermit P. Cook, RM 1c Salvatore Servidio, RM 1c
Arthur J. Anderson, RT 3c Keith A. Hurst, RT 3c
Gordon L. Kier, RT 2c Everett B. Reid, RT 2c
Alden J. Schroeder, RT 3c James C. Selvidge, RT 3c
Dorval 0. Sprong, RT 1c Robert B. Archer, MM 2c
Patrick J. Barry, MM 2c Phillip J. Bochicchio MM 2c
Earl R. Cumpiano, MM 2c Gerald A. DeBell, MM 2c
Edward A. Eble, MM 2c William C. Edie, MM 2c
Robert B. Einfeldt, MM 2c Ralph V. Englert, MM 2c
Milan M. Hampe, MM 2c Raymond M. Hampton, MM 2c
William N. Jaus, MM 2c Arthur A. Kotz, MM 2c
John. E. Kuhn, MM 2c Robert A. Masterson, MM 2c
Allen R. Mundigler, MM 2c Donald MacIntyre, MM 2c
John E. McCue, MM 2c John A. O’Connell, MM 2c
Earl R. Klein, RT 2c Myron C. Cook, MM 2c
Benjamin S. Jarrell, S 1c Paul J. Richardson, MM 2c
Richard G. Spaulding, MM 2c Richard L. Tesch, MM 2c
Paul S. Anderson FM 2c Lewis L. Cook, FM 1c Herman W. Herget, F 1c
William B. McCracken, F 1c Joyce E. Whitman, F 1c
Duane Parker, RT 3c F. A. Young, MM 1c
A. T. Murphey, MM 2c
P. R. McCray, P 3c  


Mae Jones, S 1c Laverne L. Waggon Y 3c
Verna Lenzer, S2c Marie Siejakawski, S 2c
Flora Cathell, Y 3c L. L. Peterson, S1c
N. P. Johnson, S 2c A. Mack, S 1c
C. LaTour, S 2c Z. R. Thomas, S 1c
D. Cheek, S 2c E. L. Wilson, Y 3c
M. W. Miles, S 1c B. J. Leichliter, S 2c
I. C. Hamby, S 2c

To assist in the completion of the manufacturing and test program, Lt Stapes, Lt. (j.g.) Dayger, Lt. (j.g.) Faust, and numerous enlisted personnel remained in Dayton at this time. Lt. (j.g.) Palmer returned to Dayton about September 1943 to assist Lt. Comdr. Meader in additional Engineering work for the Navy.


[to be continued]

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    WHO worked during the war? Find the Personnel section. Also, Joseph R. Desch
    WHAT were their goals? By the Numbers. Also, The US Bombe
    WHY? History of the Bombe Project A contemporary account of the reasons and the plans for their project for the Director of Naval Communications, 1944.
    WHERE was the project: In Dayton, it was in Building 26. In Washington, it was housed at the Naval Communications Annex