Accession Number : ADA221760

Title :   Roll Characteristics of an H-3 Helicopter in Calm Water and Random Waves with Several Configurations of Emergency Floats Installed,

Corporate Author : DAVID W TAYLOR NAVAL SHIP RESEARCH AND DEVELOPMENT CENTER BETHESDA MD SHIP PE RFORMANCE DEPT

Personal Author(s) : Gersten, Alvin

Report Date : JUN 1980

Pagination or Media Count : 60

Abstract : The emergency flotation system presently installed on the H-3 helicopter does not provide sufficient stability to ensure safe crew egress or shipboard recovery of the craft subsequent to water entry. A model of the H-3 helicopter has undergone static inclining experiments in calm water to determine restoring moments, dynamic experiments in calm water to determine damping and natural frequency characteristics, and dynamic experiments in random waves to evaluate maximum roll angles. Several configurations of emergency floats were installed during the experiments to compare their effectiveness in improving roll stability. Plots of maximum roll angle for operation in Sea States 2 to 5 are presented, as are tables containing maximum righting moments and damping factors. It is determined that newly configured 5,000 lb displacement floats improve roll stability significantly as compared to the floats presently installed on the helicopter. Keywords: Helicopter roll stability afloat; Emergency floats; Helicopter seaworthiness; Model experiments. (edc)

Descriptors :   *FLOATS, *HELICOPTERS, *ROLL, AIRCRAFT MODELS, ANGLES, CONFIGURATIONS, FLIGHT CREWS, DAMPING, DISPLACEMENT, DYNAMIC TESTS, EMERGENCIES, EXITS, FLOTATION, MODEL TESTS, MOMENTS, RECOVERY, RESONANT FREQUENCY, AVIATION SAFETY, SEA STATES, SEAWORTHINESS, SHIPBOARD, STABILITY, STATIC TESTS, WATER, WATER ENTRY, WATER WAVES.

Subject Categories : Helicopters
      Aerodynamics

Distribution Statement : APPROVED FOR PUBLIC RELEASE