Accident Boeing 727-46 HK-2422X, Wednesday 19 May 1993
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Date:Wednesday 19 May 1993
Time:15:06
Type:Silhouette image of generic B721 model; specific model in this crash may look slightly different    
Boeing 727-46
Owner/operator:SAM Colombia
Registration: HK-2422X
MSN: 18876/217
Year of manufacture:1965
Total airframe hrs:53930 hours
Engine model:Pratt & Whitney JT8D-7
Fatalities:Fatalities: 132 / Occupants: 132
Other fatalities:0
Aircraft damage: Destroyed, written off
Category:Accident
Location:60 km NW of Medellín -   Colombia
Phase: En route
Nature:Passenger - Scheduled
Departure airport:Panama City-Tocumen International Airport (PTY/MPTO)
Destination airport:Rionegro/Medellín-José María Córdova Airport (MDE/SKRG)
Confidence Rating: Accident investigation report completed and information captured
Narrative:
SAM Colombia flight 501, a Boeing 727-46, was destroyed when it struck the side of a mountain near Medellín, Colombia. There were 125 passengers and seven crew members on board. All were killed.
Flight 501 departed Panama City-Tocumen International Airport (PTY) on a scheduled service to Medellín (MDE) and Bogotá (BOG), Colombia.
The crew reported over the Abejorral NDB beacon at FL160, approaching Medellín. The flight was then cleared to descend to FL120. The 727 had actually not yet reached the beacon, and descended into mountainous terrain. The flight struck Mount Paramo Frontino at 11663 feet. Thunderstorm activity in the area made ADF navigation more difficult and the RNG VOR/DME had been attacked by terrorists and was unserviceable.

CAUSES (translation from Spanish language report)
The probable causes of the accident according to the information gathered during the present investigation were the following:
A. The meteorological conditions prevailing during the flight, due to the presence of an intense convective activity, resulted in the fall of the ADF's needles, in which the low quality of the ground and flight radio aids could have had an influence, spatially disorienting the commander in the cockpit, who made errors in the navigation procedures, did not lead the crew efficiently and handed over the controls to the co-pilot to conduct the flight in the adverse conditions in which it was taking place, when he should have assumed control of the aircraft in the critical situation that existed. Finally, the lack of reaction on the part of the crew, who did not take an adequate and safe decision to climb immediately as an emergency measure.
B. The controllers in Bogota and Medellin did not properly perform a positive control of the navigation of HK-2422 by not verifying the position reports of the mandatory reporting points; likewise within the transfer coordination, the appropriate parts of the updated flight plan were omitted and they forgot to warn the crew about the six minutes difference for the arrival to the true position of Abejorral.
C. The lack of a VOR-DME in the Medellin control area prevented the crew from navigating with near-accurate bearings and distances to the destination airport, which would have allowed the crew to locate themselves geographically.
CONTRIBUTING FACTORS
Lack of supervision by the company in the dispatch, before the beginning of the flight, by not providing the meteorological information available and existing on the route; which notoriously affected the attention and mood of the crew during the flight, due to the presence of meteorological conditions of intense convective activity, with the development of compact cloudiness, electrical activity, hail and ice formation.
Failure in the maintenance of the ADF's installed and in service in the aircraft, which showed low quality and low reliability, due to the repetitive reports of defective operation, which were affected by unfavorable weather conditions and the emission of the radio beacon signal, presenting false indications that could cause doubt and induced in error to the crew.
Lack of a more powerful radio beacon with which the range could have been properly established to support the airway from the Azapa position. Failure in the preparation of the internal flight plan of the SAM company, by omitting to edit in it, the mandatory positions of the Medellin control area (KOTIN), published in Letter No. 100 of April 3, 1993.
Excess of assignments in the Medellin controllers' schedules, in charge of HK 2422 handling.

Sources:

Air Safety Week 7 June 1995 (p. 4,5)
Air Safety Week 24 May 1993 (p. 4)
Flight International
Scramble 168

Statistics

  • worst accident in 1993
  • 4th worst accident of this aircraft type
  • 4th worst accident of this aircraft type at the time

Location

Images:


photo (c) EduardoR; 40 km SE of Medellín; 10 October 2009


photo (c) EduardoR; 40 km SE of Medellín; 10 October 2009


photo (c) EduardoR; 40 km SE of Medellín; 10 October 2009


photo (c) EduardoR; 40 km SE of Medellín; 10 October 2009


photo (c) EduardoR; 40 km SE of Medellín; 10 October 2009


photo (c) EduardoR; 40 km SE of Medellín; 10 October 2009


photo (c) Karl Krämer, via Werner Fischdick; San Andres Island Airport (ADZ); February 1987

Revision history:

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