The USS Appalachian was launched on January 29, 1943. From May-July 1946, the ship served as headquarters for press representatives reporting on Operation Crossroads, the atomic bomb tests carried out at Bikini Atoll. During this time, the USS Appalachian was dubbed the “Big Apple.”
     
“From the Appalachian’s special radio teletypes, reporters will be able to send more than 200,000 words a day. Sailing from Hawaii with the ‘Big Apple’ ...” was printed in Time magazine on June 17, 1946.
   
   
Wikipedia: USS Appalachian
USS Appalachian (AGC-1) was the lead ship of the Appalachian class amphibious force flagships of the United States Navy. She was laid down under a Maritime Commission contract (MC hull 200) on 4 November 1942 at the Federal Shipbuilding & Drydock Company in Kearny, New Jersey; launched on 29 January 1943, sponsored by Mrs. John Frank Mclnnis; acquired by the Navy on 27 February 1943; converted at Brooklyn, N.Y., by the Todd Shipbuilding Company for naval service as an amphibious flagship; and commissioned on 2 October 1943, with Captain James M. Fernald in command.
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Appalachian departed Japan on 22 November 1945, bound for the west coast of the United States. After reaching the United States, she remained at San Francisco until 12 April 1946 when she was assigned to Joint Task Force 1 which was being established for Operation Crossroads, the atomic bomb tests to be carried out that summer at Bikini Atoll. During the months of May, June, and July, Appalachian served as a headquarters for press representatives before returning to San Francisco on 16 August.
         
Time magazine
The Press: Assignment A-Bomb
Monday, June 17, 1946
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From the Appalachian’s special radio teletypes, reporters will be able to send more than 200,000 words a day. Sailing from Hawaii with the “Big Apple” will be her sister ship, the U.S.S. Panamint, with the U.N. delegation, scientific observers and four more newsmen. The newsmen aboard the “Big Apple” and the Panamint will witness The Drop from 15 or 20 miles away, will probably not get their best stories until their ships move in close to look at the devastation later. Of the 169 newsmen converging on Bikini, only three reporters and a half-dozen photographers will actually fly over the target when the bomb run is made. But all correspondents had been investigated, shot full of injections, and issued enough instructions for an invasion. Some methodical Navy men had even made every newsman sign a document waiving right to any invention he might think up as a result of watching ,the bomb test.
 
Newspapers.com
17 June 1946. Boston (MA) Daily Globe, “Globe Man Bikini-Bound” by John G. Harris, pg. 24, col. 1:
U. S. S. APPALACHIAN, June 13—Massachusetts is n’t the only place Bay Staters are running for office.
 
There’s a hectic “contest” full of chuckles aboard the “Big Apple” right now to see who will get the honor of succeeding old King Juda as bossman on Bikini…and right in the middle of the “contest” is a man well known on Boston newspaper row.
 
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22 June 1946, The Weekly Call (Birmingham, AL), pg. 4, col. 3:
Newsmen Admit
Apprehension of
A-Bomb Mission
By WALTER A. SHEAD
WNU Correspondent
ABOARD USS APPALACHIAN (Via Navy Radio)—Civil and military welcoming committees out of the way, with the beauty and color of the Paradise of the Pacific a pleasant memory interlude in the midst of this serious military experiment the “Big Apple” today has her nose pointed westward on the second leg of our hop towards Bikini atoll and the atomic bomb test, the results of which may revolutionize naval tactics
 
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24 June 1946, St. Louis (MO) Post-Dispatch, The Everyday Magazine, pg. 1C, col. 1:
Times Have Changed
Aboard ‘Big Apple’
By Keith Wheeler
A Special Correspondent of the Post-Dispatch
ABOARD U. S. S. APPALACHIAN, June 24.
HOW the U.S.S. Appalachian, or “Big Apple” as she is called by those who dote on her, came to be chosen as press ship for Operation Crossroads is a small and slightly ironic mystery.
 
Newspapers.com
26 June 1946, Cincinnati (OH) Enquirer, pg. 15, col. 1 photo caption:
The Appalachian, flagship of a wartime amphibious force, dubbed “The Big Apple” by her crew, is headquarters for press, radio and photographer correspondents going to observe the Bikini Atoll atomic bomb test in the Marshall Islands in early July.
 
Newspapers.com
2 July 1946, Daily Dispatch (Moline, IL), pg. 17, col. 3 photo:
Radio Voice of Bikini Atom Bomb Tests
AIRVIEW OF THE U. S. S. APPALACHIAN, former combined operations flagships in the Pacific campaigns from Tarawa to Tokyo, from which all communications for “Operation Crossroads,” the Bikini atom bomb test are sent to the world. Carrying 116 press correspondents, in addition to foreign and scientific observers, the “Big Apple” is equipped with 6 radio teletypes; 2 radiophoto transmitters and television equipment which enabled observers to view the A-blast. (International soundphoto.)