PPRuNe Forums - View Single Post - Helicopter crash off the coast of Newfoundland - 18 aboard, March 2009
Old 11th Feb 2011, 20:34
  #865 (permalink)  
zalt
 
Join Date: Mar 2002
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The TSB report is a tour de force.

Its important not to over concentrate on the indications of oil loss when the root cause is the repeat failure of simple component and a sub-standard gearbox.

However, anyone who does want to analyse the indication aspects need to consider the following:

1) The Amber Caution was followed by a Red Warning so fast that the crew didn't have chance to notice the first (this would not have been a surprise to Sikorsky who afterall wanted the bypas valve activated in just 5s to stop a rapid and catestrophic oil leak)

2) The FSI checklist in use was however written with the assumption that their would be a much more gradual leak (as used in all training scenarios).

3) As a result the NHP had to thumb page thru page to find the Oil P Warning as it wasn't in the index.

4) The fact that there had been 4 oil system S-92 emergencies in the past of which 3 were pump failures and 1 that "was not considered a cause for concern since the problem was attributed to another company's field repair".

5) Sikorsky had concealed that during the 6 August 2002 initial certification loss of lubricant test (when they drained the MGB and to just the 1,3 gallon residual oil) the MGB "suffered a catastrophic failure about 11 minutes after the test was started...due to excessive temperature caused by lack of lubrication".

6) As Brains said: Finding yourself suddenly with zero pressure (say) in the cruise at 9,000 is going to eat up lot of that 11 minutes (as demonstrated) getting to the ground/water.

7) As the AAIB described the S-92 this week, it does have "sub-optimal switch locations and markings" in the cockpit Air Accidents Investigation: Sikorsky S-92A, G-SARC

8) The sea state was at the limits of the basic S-92 floats (as Cougar had not bought the enhanced floats - though they were not available when the S-92 first entered service)

Sikorsky had 6.5 years to address the MGBs shortcomings, the Cougar crew had just seconds.
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