Vice Admiral William S. Sims, Commander, United States Naval Forces Operating in European Waters, to Secretary of the Navy Josephus Daniels
3rd September 1917
From:- Force Commander
To :- Secretary of the Navy (Operations).
Subject:- Transporting troops and supplies to Europe.
1. The following information is forwarded for the information of the Department. The data is furnished by the British Admiralty and is based on the experience of supplying troops in France during the present war. It is believed this data is approximately correct.
2. PERSONNEL. To transport a division of 20,000 men complete in every respect, with heavy gear, including horses, land transport and so forth, there are required approximately 150,000 gross tons of shipping. Vessels from the United States should make a round trip every seven weeks or seven complete trips a year. 150,000 gross tons of shipping would, therefore, transport 140,000 men in a year. To transport a million men across the Atlantic in the year would take more than a million gross tons of shipping.
3. STORES. A division requires each week 2,200 tons of stores of all descriptions, including food, munitions and so forth.
4. Store ships should make a round trip in eight weeks or six and a half trips a year. To supply a million men in Europe, there would be required 880,000 tons of shipping continuously employed. It should be understood, however, that this maximum amount of shipping for carrying stores would not be reached until a million men had actually been transported.
5. After all the troops had arrived, the full amount of shipping for stores would be required together with the shipping necessary to carry reinforcements, remounts and so forth.
6. It is likely that a number of hospital ships would be needed as well.
Wm S. Sims,
TROOP TRANSPORT SPECIAL LETTERS 7 Copies
TROOP SHIPS REQUIRED FOR TRANSPORT OF ARMY TO FRANCE
The following vessels have carried troops across the Atlantic, and the number of gross tons required for each man
is averages about 6 tons gross. The following data is available:
The ratio in the smaller vessels is one man to 5.7
In the OLYMPIC it is one to 7.7. We may assume that under average conditions it will take six gross tons to transport one man. This is merely for troop transport and is entirely aside from the question handling baggage, artillery, horses, supplies and so forth, although on the type of vessel employed as a troop transport a limited amount of baggage and so forth can be carried in addition to the troops.
The average vessel will make a round trip from America in about six weeks. Assuming that it was necessary to put a million troops in France by May 1, starting in October (a period of 30 weeks) there would be time enough for five round trips each carrying 200,000 troops.
On the basis of six gross tons to one man, those would be required one million two hundred thousand tons gross shipping, or 150 ships of 8,000 tons gross continuously employed in this business.
The United States has taken over and is modifying sixteen former German liners, having a total gross tonnage of 275,000. Assuming that all sixteen of these vessels could be ready at once, they would bring over each trip 46,000 men, and up to May 1, assuming transport began the 1st October, they would bring over 130,000 men, and if continued for a year they would bring over 400,000 troops.
It should be understood that the foregoing appertains merely to the amount of tonnage required for troop transports. The supply transport is all in addition to the foregoing.