Yes. The Army Regulation 25–50 Preparing and Managing Correspondence - Section III Specific Correspondence Guidance 1–18 states:
Correspondence may be signed in blue or black ink. Black ink will be used for date stamps.
Rules for Paper 1-16:
Paper used for Army correspondence generally will be the standard size (8 1⁄2 by 11 inches). Use computer-generated letterhead for the first page of all memorandums and letters except when an approved form is prescribed. Use plain white paper for continuing pages.
Rules for Type of fonts and sizes 1–17:
When creating official correspondence, use type fonts and sizes that make the correspondence easy to read and understand. The following guidelines will provide the best results:
a. A font with a point size of 12 is recommended.
b. Preferred type font is Arial.
c. Unusual type styles, such as Script, will not be used in official correspondence.
Read more of the Army Regulation 25–50 at Army Publishing Directorate.
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