Document ID: chunk:federal_register_of_legislation:F2008L02668:body:0:p3
Version: federal_register_of_legislation:F2008L02668
Segment Type: other
Provision Reference: 
Character Range: 5740–7458

Within 6 000 hours TIS after the effective date of this Amendment.
             For Requirement 4 - Within 6 000 hours TIS after the effective date of this Amendment.
             For Requirement 5 - Within 6 000 hours TIS after the effective date of this Amendment.
             For Requirement 6 - Prior to accomplishing Requirement 5.
             This Amendment becomes effective on 31 July 2008.
Background:  Incidents of airspeed mismatch between the pilot, co-pilot and standby airspeed indication have been reported to Transport Canada.  These events are believed to be caused by contamination within the pitot lines and/or blockage within the pitot static probes.  Blockage of a probe's pitot drain may allow sufficient moisture to enter the probe's internal pitot line such that freezing may occur under certain conditions, causing a blockage to the pitot line.
             The Original issue of this Directive was an interim action to avoid the potential for erroneous airspeed information, by mandating the periodic cleaning of the pitot static probe drain hole and the pitot lines.
             To mitigate potential blockage of the pitot static system, Bombardier has introduced modifications to improve the water drainage capabilities of the pitot static system and the freeze protection capabilities of the pitot probes.  Therefore, this Amendment is issued to mandate the incorporation of the above-mentioned modifications as terminating action to the repetitive maintenance requirements mandated by the original issue of this Directive.

   The original issue of this Directive became effective on 4 August 2005.

James Coyne
Delegate of the Civil Aviation Safety Authority

20 June 2008