For the purpose of this subchapter, except section 3504—

(1) “active service” has the meaning given it by section 101 of title 37;

(2) “a retired member of a uniformed service” means a member or former member of a uniformed service who is entitled, under statute, to retired, retirement, or retainer pay on account of his service as such a member; and

a preference eligible employee who is a retired member of a uniformed service is considered a preference eligible only if—

(A) his retirement was based on disability— (i) resulting from injury or disease received in line of duty as a direct result of armed conflict; or (ii) caused by an instrumentality of war and incurred in the line of duty during a period of war as defined by sections 101 and 1101 of title 38;

(B) his service does not include twenty or more years of full-time active service, regardless of when performed but not including periods of active duty for training; or

(C) on November 30, 1964, he was employed in a position to which this subchapter applies and thereafter he continued to be so employed without a break in service of more than 30 days.

Except as otherwise provided by this subsection and section 3504 of this title, this subchapter applies to each employee in or under an Executive agency. This subchapter does not apply to an employee whose appointment is required by Congress to be confirmed by, or made with the advice and consent of, the Senate or to a member of the Senior Executive Service or the Federal Bureau of Investigation and Drug Enforcement Administration Senior Executive Service.

(Pub. L. 89–554, Sept. 6, 1966, 80 Stat. 428; Pub. L. 94–183, § 2(8), Dec. 31, 1975, 89 Stat. 1057; Pub. L. 95–454, title IV, § 404(a), Oct. 13, 1978, 92 Stat. 1165; Pub. L. 100–325, § 2(e), May 30, 1988, 102 Stat. 581; Pub. L. 102–83, § 5(c)(2), Aug. 6, 1991, 105 Stat. 406.)