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Frequency of the "push-pull effect" in U.S. Air Force fighter operations
V J Michaud1, T J Lyons, C M Hansen
1U.S. Air Force School of Aerospace Medicine, Brooks AFB, TX 78235-5252, USA.
Aviation, Space, and Environmental Medicine
|November 18, 1998
Summary
The push-pull effect (PPE) occurs in U.S. Air Force fighter training, potentially increasing accident risk. Further research is needed to understand physiological responses and develop countermeasures.
Area of Science:
- Aerospace Medicine
- Human Factors Engineering
- Physiology
Background:
- The push-pull effect (PPE), a reduction in +Gz tolerance after exposure to <+1 Gz, has been observed in centrifuge studies.
- Adverse cardiovascular responses associated with PPE are known, but maneuvers causing the push-pull effect (PPEM) in U.S. Air Force (USAF) fighter aircraft remain unstudied.
- The operational frequency and extent of PPEMs in fighter aircraft are currently unknown.
Purpose of the Study:
- To investigate the presence and frequency of push-pull effect maneuvers (PPEMs) during U.S. Air Force (USAF) fighter aircraft air combat training.
- To quantify the Gz profiles associated with observed PPEMs in operational training environments.
Main Methods:
- Review of head-up display (HUD) videotapes from F-15 and F-16 air combat training missions.
- Identification and analysis of engagements containing PPEMs, noting frequency and Gz profile magnitudes.
Main Results:
- PPEMs were identified in 11% to 67% of reviewed training engagements, averaging 32% overall.
- Observed PPEMs included segments below +1 Gz, with an average magnitude of 0.0 to 0.5 Gz and duration of 3.5 to 5 seconds.
Conclusions:
- PPEMs are a current reality in USAF fighter aircraft air combat training.
- The presence of PPEMs poses a significant operational risk for accidents.
- Continued research into the physiological effects of PPE and the development of countermeasures are warranted.
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