14 C.F.R. § 152.307 Retention of records.
Title 14 - Aeronautics and Space
Each sponsor or planning agency shall retain, for a period of 3 years after the date of submission of the final expenditure report— (a) Documentary evidence, such as invoices, cost estimates, and payrolls, supporting each item of project costs; and (b) Evidence of all payments for items of project costs, including vouchers, cancelled checks or warrants, and receipts for cash payments.
Title 14: Aeronautics and Space
PART 152—AIRPORT AID PROGRAM
Subpart D—Accounting and Reporting Requirements
§ 152.307 Retention of records.
