AIRCRAFT ACCIDENT REPORT - ROCKY MOUNTAIN AIRWAYS, INC., DEHAVILLAND DHC-6 TWIN OTTER N25RM NEAR STEAMBOAT SPRINGS, COLORADO, DECEMBER 4, 1978

About 1945 m.s.t. on December 4, 1978, a Rocky Mountain Airways, Inc., DHC-6 Twin Otter, operating as Flight 217, crashed on a mountain about 8 nmi east-northeast of Steamboat Springs, Colorado. The flight had departed Steamboat Springs about 1855 on a scheduled flight to Denver, Colorado, but was returning to Steamboat Springs after encountering severe icing conditions. The flight crashed into a mountain at the 10,530-ft level. Of the 22 persons aboard, 2 died of injuries received in the crash. The aircraft was destroyed. According to official observations, the weather at Steamboat Springs about 25 min before the accident consisted of an estimated 2,000-ft overcast ceiling and 6-mi visibility in freezing rain. According to surviving passengers, after the accident, snow was falling at the crash site and a strong wind was blowing and gusting from the west. The National Transportation Safety Board determines that the probable cause of this accident was severe icing and strong downdrafts associated with a mountain wave which combined to exceed the aircraft's capability to maintain flight. Contributing to the accident was the captain's decision to fly into probable icing conditions that exceeded the conditions authorized by company directive.

  • Supplemental Notes:
    • Paper copy also available on subscription, North American Continent price $40.00/year; all others write for quote.
  • Corporate Authors:

    National Transportation Safety Board

    Bureau of Accident Investigation, 800 Independence Avenue, SW
    Washington, DC  USA  20594
  • Publication Date: 1979-5-3

Media Info

  • Pagination: 38 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00198502
  • Record Type: Publication
  • Source Agency: National Technical Information Service
  • Report/Paper Numbers: NTSB-AAR-79-6
  • Files: TRIS
  • Created Date: Oct 17 1979 12:00AM