delivered the opinion of the court:
The question here presented involves the right of an officer in the Medical Corps of the Army, with the rank of captain, to increase of pay on account of special detail to flying or aircraft duty as a flight surgeon. The applicable *738statutes are the acts of June 3, 1916,1 39 Stat. 175, and June 4, 1920,2 41 Stat. 769.
On October 16, 1919, the plaintiff received special orders as follows:
“ Under the provisions of par. 1269%, A. R., the following named officer is hereby announced as being on duty requiring him to participate regularly and frequently in aerial flights from the date as set opposite his name.
“ Captain Samuel E. Brown, M. C., September 13th, 1919. ‡ ‡ $
“ By order of Lieut. Colonel Johnson.”
Thereafter the plaintiff continued on duty required of him by said order until January 29, 1921, when he was relieved from aircraft duty by the following order:
“ 7. Pursuant to instructions contained in 1st indorsement, War Department, Adjutant General’s Office, dated January 20, 1921, the following named officers, Medical Corps, are relieved from duty requiring them to participate regularly and frequently in aerial flights, as required by paragraph 1269%, Army Begulations, effective this date.
*******
“ Captain Samuel E. Brown, Medical Corps.”
The question here presented has been passed upon and so clearly settled by the decisions of this court that it seems only necessary to refer to the cases. Luskey v. United States, 56 C. Cls. 411, 262 U. S. 62; Marshall v. United States, 59 C. Cls. 900; Clark v. United States, 60 C. Cls. 589; Matteson v. United States, 60 C. Cls. 880; Bradshaw v. United States, 62 C. Cls. 638; Lynch v. United States, 63 C. Cls. 91; Emmons v. United States, 63 C. Cls. 121; Carleton v. United States, 64 C. Cls. 564; Arnold v. United States, 65 C. Cls. 43; Johnson v. United States, 67 C. Cls. 318.
*739In. each of these cases the basic principle was that the right to pay went hand in hand with the assignment to the duty. It is clear from all the cases that actual flying or participation in flights was not the test of the right to pay. The fact that in all but one of the cases actual flights took place is not important. The assignment to the duty and the obligation to perform it are the touchstone of the right to pay.
The order of assignment imposed on the plaintiff a new and hazardous duty. The department order required preparation and readiness for a very dangerous duty and exposure in the air to accident in observing the qualities and qualifications of the pilot. Presumably he did participate in flights contemplated by his assignment; but whether he did or not, he stood by ready to do so — a case where he also serves who only stands and waits.
The pay was not by the act fixed upon the basis of the number of flights made, or upon flights actually made, but upon the detail to the duty involved. The duration of the detail constituted a service for which the officer had to keep prepared. During the whole period for which recovery is sought he was under orders of this detail. The increased pay is fixed for the period “ while on duty that requires him to participate regularly and frequently in aerial flights.” He was lawfully detailed to such duty and during the period of detail was entitled to the increased pay allowed by the statute. This pay which was legally given him and afterward illegally deducted he is entitled to recover, except the $50 checked against plaintiff on October 31, 1921, as to which the statute of limitations had run at the time this suit was brought. Plaintiff is entitled to recover $1,130, and it is so ordered. •
Williams, Judge; Littleton, Judge; Green, Judge; and Booth, Chief Justice, concur.“ Each aviation officer authorized by this act shall, while on duty that requires him to participate regularly and frequently in aerial flights, receive an increase of .twenty-five per centum in the pay of his grade and -length of service under his commission.”
“ Flying units shall in all eases be commanded by flying officers. Officers and enlisted men of the Army shall receive an increase of 50 per centum of their pay while on duty requiring them to participate regularly and frequently in aerial flights.”