Swiss Cheese
31st Jul 2007, 11:09
Prelim report on S61 Tenerife crash published last month. MRB failure of Black Blade highlighted, with indications that BIM system/refilling valve on that Black Blade were leaking days before accident, and that maintenance as per MM carried out.
20 mins into the flight, the Cockpit BIM lights up, we know this because the Pilot announces "Look we are at BIM PRESS"and nothing more is heard of relevence on the CVR until the Black Blade lets go 30 mins later. My reading of this is that everyone assumes it is the unreliability of the monitoring system rather than a fatigue crack. Hence the blade lets go with the inevitable consequences.
Blade had 6750 hrs on it. I suppose we shall never know, outside a courtroom, what advice was going to and from UTC and Helicsa about the reliability of the BIM system.
20 mins into the flight, the Cockpit BIM lights up, we know this because the Pilot announces "Look we are at BIM PRESS"and nothing more is heard of relevence on the CVR until the Black Blade lets go 30 mins later. My reading of this is that everyone assumes it is the unreliability of the monitoring system rather than a fatigue crack. Hence the blade lets go with the inevitable consequences.
Blade had 6750 hrs on it. I suppose we shall never know, outside a courtroom, what advice was going to and from UTC and Helicsa about the reliability of the BIM system.