Engine Performance
Analysis for Engine
 Health Management Plus

Engine Health Management Plus (EHM+) is the United States Air Force (USAF) Propulsion program that is used to optimize operational readiness through affordable, integrated, embedded diagnostics and prognostics. The goal of EHM+ is to tie together Engine Trending and Diagnostics (ET&D) and Reliability Centered Maintenance (RCM) to enable the commander to make decisions based on weapon system capability to meet real-time operational needs.

Working closely with the USAF, Southwest Research Institute (SwRI) supports EHM+ to:

  • Improve maintenance ability and responsiveness
  • Increase operational availability
  • Reduce life cycle total ownership costs

Assessing Engine Health

ET&D is a program integrating hardware, software, technical documents, training, maintenance, and diagnostic/prognostic processes to quantify and monitor/manage engine health. Effective use of ET&D can reduce engine flight safety risk, improve reliability, and optimize life cycle costs.

RCM is an integral part of engine life management. RCM is an analytical process to determine the appropriate failure management strategies, including preventive maintenance requirements and other actions that are warranted to ensure safe operations while balancing readiness and costs.

EHM+ Efforts

SwRI has served as an Independent Verification and Validation (IV&V) agent for the USAF by reviewing engine performance analysis software, making recommendations to improve engine analysis techniques, and by performing analyses on a case by case basis for problem engines. These types of analyses have been conducted on a number of engines, including:


Engine TF33 TF34 F108 F100 F101 F110 F118 TF39 T56
A-10 KC-135 RF-15
B-1 F-16 B-2 C-5 C-130
SwRI has performed EHM+ activities in support of USAF Engines and their Weapon Systems
Image:Engine Health Management Plus data is destined to be stored in the EHM+ database, so that EHM+ data can be accessed by users of the data through programs such as the Jet Engine Trending Tool (JETT).

Engine Health Management Plus data is destined to be stored in the EHM+ database, so that EHM+ data can be accessed by users of the data through programs such as the Jet Engine Trending Tool (JETT).

Unique engine performance analyses is also provided, utilizing advanced, automated anomaly detection, fault detection, sensor validation, and diagnostic algorithms. These algorithms detect abnormal engine performance that may appear as mean or variance shifts, adverse trends, or other patterns in the data, alert users of the impending failures, and then direct them to the cause of the anomaly. This type of analysis has been applied to the F100, F108, TF39, and T55 (CH-47) engines, and is applicable to many others.

SwRI has been involved in developing requirements and enhancements for RCM programs operated at field locations, and has supported RCM tools with familiarization and technical documentation development.

How EHM+ Data Are Stored

EHM+ data are stored in a data repository center so the data can be accessed by users through programs such as the SwRI-developed Jet Engine Trending Tool (JETT). This allows users to view engine data across a wide range of varying detail: from viewing information about a single engine’s performance or maintenance history, to seeing aggregated metrics at the aircraft, base, major command, and fleet levels.

Related Terminology

aircraft engine performance  •  engine health management plus  •  EHM+  •  EHM Plus  •  engine performance analysis  •  engine trending analysis  •  jet engine trending tool  •  JETT  •  aerospace engineering

Benefiting government, industry and the public through innovative science and technology
Southwest Research Institute® (SwRI®), headquartered in San Antonio, Texas, is a multidisciplinary, independent, nonprofit, applied engineering and physical sciences research and development organization with 9 technical divisions.