# Project 673504 — Propulsion (PP)

**Program element:** 0604840F — F-35 C2D2  
**Project:** 673504  
**Component:** U.S. Air Force  
**Appropriation:** 3600 — RDT&E, Air Force  
**Budget Activity:** 7 — Operational System Development  
**Vintage:** President's Budget PB2027  
**Canonical URL:** https://hitchintel.com/programs/0604840F/673504  
**Parent:** https://hitchintel.com/programs/0604840F

## Summary

Project 673504 — Propulsion (PP) requests $94.1M in FY2027, 8.3% of the $1.13B requested for program element 0604840F, down 22% on FY2026. 1 R-2A activity decomposes the request. Pratt & Whitney is the largest named R-3 performer at $90.8M, 96% of the project's FY2027 R-3 total.

## Funding profile

| Fiscal Year | Estimate Type | Amount ($M) |
|---|---|---|
| FY2025 | Actual | 166.1 |
| FY2026 | Enacted | 121.0 |
| FY2027 | Request | 94.1 |
| FY2028 | Outyear | 229.2 |
| FY2029 | Outyear | 247.5 |
| FY2030 | Outyear | 224.6 |
| FY2031 | Outyear | 214.6 |

> Estimate types are not summed. This project is one leaf of PE 0604840F; the PE total is the sum of its projects, never added to them.

## What project 673504 buys

Propulsion F135 projects within the Continuous Capability Development & Delivery (C2D2) are provided for developmental efforts for propulsion systems and test engine requirements such as Block 4 Integrated Flight Test Support, Engine Flight Test Mechanics, Flight Test Engineering, Engine Hardware, Test Engine Procurements, research, component, and capability development, prototypes, various studies, costs integral to support the developmental stages for F-35 engine modernization, affordability drivers for top engine availability degraders, and improvement to support the F135 Propulsion System for the F-35 Air Vehicle. Testing and development of the three F-35 aircraft variants require engine propulsion funding to enable continued flight hours. Flight hours are budgeted and planned to meet the Block 4 Flight Test timelines and required Flight Test support. Transition of Flight Test Support requirements to organic capability includes efforts performed by contractor and government installations, Autonomic Logistics Information System / Operational Data Integrated Network (ALIS/ODIN) transition, replacement of development-only hardware, and updating Joint Technical Data (JTD) packages as required. The F-35 engine is being modernized with the F135 Engine Core Upgrade (ECU), which is part of the Engine, Power, and Thermal Management Modernization (EPM) program. The F135 ECU is projected to recapture engine life for increased affordability while providing additional power and cooling capacity to support future mission systems enhancements for the global F-35 fleet. This program element included all necessary expenses required to manage, execute, and deliver weapon system capability. The use of such program funds would be in addition to the civilian pay expenses budgeted in program elements 0605829F, 0605831F, 0605833F, and 0605898F. Funding allocations at the project level have historically been subject to change due to the complexity of the F-35 budget structure and cost share ratios. The program will ensure any within-PE adjustments during execution year are reflected in future budget submissions. The FY2027 request for Propulsion includes $94,102 thousand of discretionary and $223,408 thousand of mandatory for a total of $317,510 thousand for acceleration of Engine and Power Thermal Management timelines.

**R-3 lines of work:** Product Development; Support.

## Named R-3 performers

| Performer | $M | Share of this project's FY2027 R-3 total |
|---|---|---|
| Pratt & Whitney | 90.8 | 96% |

> Budget-justification contract funding, not obligations. Shares need not reach 100% — unnamed and government work is in the denominator.

## Activities (R-2A) — 1

| Activity | FY2025 | FY2026 | FY2027 | Move | Page |
|---|---|---|---|---|---|
| Propulsion (PP) | 166.1 | 121.0 | 94.1 | −22% | [a0](https://hitchintel.com/programs/0604840F/673504/a0) |

> Activities carry the prior, current and budget year only — no five-year plan. In the request year they partition this project exactly; in earlier years they can under-cover it.

### Propulsion (PP)

Continue Organizational Level support for all F135 Flight Test Block 4 Propulsion Systems and Intermediate Level support for a select few Propulsion systems as required by the Test & Evaluation team. This will include Engine Flight Test Mechanics, Flight Test Engineering, Engine Hardware, Test Engine Procurements, and other associated…

Full year-by-year narrative: https://hitchintel.com/programs/0604840F/673504/a0

## What is NOT on this page

Congressional marks, the R-2 mission description and acquisition strategy, the industry vs government split of the whole request, and related program elements are recorded at **program-element** grain — an NDAA mark lands on a PE, never on a project. They are at https://hitchintel.com/programs/0604840F.

## Source & machine access

- **Source:** FY2027 Department of the Air Force RDT&E Budget Justification, Exhibits R-2/R-2A/R-3, PE 0604840F project 673504 (PB PB2027).
- **MCP:** `mcp.hitchintel.com` — `budget_get_program_element(pe="0604840F")`.

*HitchAI is an independent intelligence service, not affiliated with the U.S. Department of Defense. Budget figures are requests/estimates, not obligations.*