Pilot certificate required?

14 CFR 61.3 (copied 24NOV2018)

61.3 Requirement for certificates, ratings, and authorizations.

(a)Required pilot certificate for operating a civil aircraft of the United States. No person may serve as a required pilot flight crewmember of a civil aircraft of the United States, unless that person:

(1) Has in the person's physical possession or readily accessible in the aircraft when exercising the privileges of that pilot certificate or authorization -

(i) A pilot certificate issued under this part and in accordance with § 61.19;