What was found
(CAN) DISCLOSURE LETTER TO BE RECEIVED ON 31-MAY-19. IT WAS DISCOVERED DURING THE CERTIFICATION OF AN HSTECU THAT ON HSTA S/N 301, ONE OF THE 2 COMPRESSION NO-BACK PAWLS WAS MIS-INSTALLED. THE MIS-INSTALLED PAWL CANNOT PERFORM ITS INTENDED FUNCTION. THE AIRCRAFT AFFECTED ARE ALL CHALLENGER 300 AND 350 (BD-100-1A10) MODELS AND IS BEING ASSESSED AS PART OF CONTINUING AIRWORTHINESS PROJECT BD1-CA-27-0055.