An appropriation is the account Congress actually funds. Every dollar DoD spends is charged to one, and the account determines what the money may buy, how long it stays available, and which committee controls it. Everything downstream in the budget hierarchy hangs off this layer.
The four-digit account number is the anchor. 3600 is Air Force RDT&E; 2040 is Army procurement of “other” equipment. Learn to read the number and the rest of the budget becomes navigable.
The RDT&E accounts
Research, development, test and evaluation. Two-year money: available for obligation across the fiscal year of appropriation and the one following.
- RDT&E, Army — account 2040
- RDT&E, Navy — account 1319
- RDT&E, Air Force — account 3600
- RDT&E, Defense-Wide — the OSD, DARPA, SOCOM and agency account
- Defense-Wide RDT&E detail
Procurement
Three-year money. Buys production quantities of things already developed.
Accounts by number
- Appropriation_0400 · Appropriation_1319 · Appropriation_2040 · Appropriation_3600 · Appropriation_3620F
How this fits
The hierarchy runs appropriation → budget activity → program element → project. Read DoD_Budget_Hierarchy for the full structure, budget activities for the maturity bands inside RDT&E, and PPBE for how these accounts get built in the first place.
Money that Congress appropriates still has to be spent under the acquisition system and the FAR. Unfunded needs travel a separate path: see Unfunded_Requirements.