Product Improvement Test of UH-1B Tail-Boom Fitting

Abstract

Numerous cracking failures of the original production UH-1B upper- left-hand tail-boom attaching fittings occurred in the field when the helicopters were operated at high gross weights. The fittings cracked approximately 18 inches aft of the tail boom bulkhead. To correct this problem, a stronger fitting was designed and incorporated (MWO 55-1520-211/28) in the UH- 1B fleet. In September 1964, one of the modified fittings cracked after 553 hours of operation at high takeoff gross weights (reference d). The crack was two inches aft of the tail-boom bulkhead and extended through the first rivet hole. Subsequently, several similar failures were reported to have occurred in the Republic of Vietnam in UH-1B Helicopters after approximately 500 hours of operation.

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Document Details

Document Type
Technical Report
Publication Date
Jun 29, 1966
Accession Number
ADA030825

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Aircrafts
  • Army Aviation
  • Bulkheads
  • Center Of Gravity
  • Field Conditions
  • Helicopters
  • Missouri
  • Oscillographs
  • Strain Gages
  • Test And Evaluation
  • Test Vehicles
  • United States
  • Vehicles
  • X Rays

Readers

  • Aerial Delivery - Logistics and Supply Chain Management.
  • Logistics and Supply Chain Management.
  • Materials Science (Mechanical Engineering).