Prolonged restricted sitting effects in UH-60 helicopters

Area of Science:

• Aviation physiology
• Human factors engineering
• Occupational health

Background:

• Increased flight mission lengths for U.S. Army Black Hawk UH-60 crewmembers due to advances in flight technology.
• Reports of pilot discomfort and paresthesia linked to UH-60 seat design and high-pressure areas.
• Pilot discomfort negatively impacts situational awareness and increases injury risk.

Purpose of the Study:

• To examine the effects of prolonged restricted sitting in a UH-60 helicopter seat.
• To assess the impact on subjective discomfort, sensory function, and vascular measures in the lower extremities.

Main Methods:

• 15 healthy male subjects meeting flight physical requirements participated.
• Subjects sat in an unpadded UH-60 pilot seat for 4 hours.
• Measurements included subjective discomfort, sensory function, and vascular function.

Main Results:

• Subjective discomfort significantly increased over 4 hours.
• Lower extremity sensory function diminished along the S1 dermatome.
• Skin temperature decreased on the lateral and anterior aspects of the ankle.

Conclusions:

• Prolonged sitting in UH-60 seats exacerbates discomfort.
• Potential mechanisms involve peripheral nervous or vascular system alterations.
• Further research is required to elucidate the etiology of pain and paresthesia.