#2 ENG COWLING LATCHES BECOME UNSECURED; ALLOWING HATCH TO OPEN INFLT. RETURN LAND.

Narrative

AFTER A NORMAL TKOF; WHICH WAS PRECEDED WITH A NORMAL PREFLT AS WELL AS NORMAL FIRST FLT OF THE DAY SYS CHKS; WE WERE CLBING AS PER OUR SPOKANE 5 SID. WHEN THE FLT ATTENDANT CALLED ON THE INTERPHONE TO ADVISE THE PLTS THAT A PAX HAD NOTICED 2 OF 3 COWLING ENG LATCHES ON THE R SIDE #2 ENG; HAD POPPED OPEN; INTO THE WIND; AS WE MADE OUR FIRST TURN FROM RWY HDG TO THE E AS PER ATC. THE PAX LATER TOLD THE PLTS THAT THE LATCHES APPEARED TO BE SECURE DURING GND OPS AND DURING THE RUNUP (AS PER FIRST FLT OF THE DAY). FURTHERMORE; I; BEING THE FO; IT IS MY RESPONSIBILITY TO ENSURE A PROPER PREFLT. I DID PREFLT THE ACFT AND SAW THAT THE ENG COWLS WERE SECURE AND LATCHED PROPERLY. PERHAPS THE PREFLT AFTER MAINT SHOULD INCLUDE A LIFT AS A LADDER TO PROPERLY CHK SECURITY OF OTHERWISE UNREACHABLE COWLS; LATCHES AND THE LIKE. ALSO; THE DESIGN OF THE LATCH MUST BE CHANGED TO PREVENT AN 'APPEARED LOCK;' IE; MAKING IT IMPOSSIBLE TO STOW THE LATCHES IN A LOCKED POS UNLESS THESE LATCHES ARE 'REALLY' LOCKED INTO PLACE. A RETURN TO FIELD WAS ACCOMPLISHED TO HAVE MAINT RELOCK THE LATCHES CORRECTLY. I RECOMMEND THAT ON THIS ACFT; DURING PREFLT; ONE MUST PHYSICALLY CHK COWLS TO BE IN THEIR LOCKED POS. A VISUAL INSPECTION WILL NOT INSURE THAT THE COWLS ARE PROPERLY SECURED. ALSO; I ENCOURAGE PAX WITH A 'GOOD EYE' TO LOOK OUTSIDE TO OBSERVE UNUSUAL CONFIGNS OR SITS THAT WE CREW MEMBERS CANNOT SEE. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR IS AN FO AND FLIES THE DORNIER 328 TURBOPROP; AN LTT CATEGORY ACFT. IT IS A HIGH WINGED ACFT. THE PLT THAT PERFORMS THE PREFLT IS ONLY ABLE TO VERIFY THE 'CLOSED AND LATCHED' POS OF THE COWL LATCHES BY A VISUAL INSPECTION. THERE IS NOT ANY WAY FOR THE CREW MEMBER TO CLB UP HIGH ENOUGH TO PHYSICALLY CHK THE LATCHES IN A CLOSED AND LOCKED POS. APPARENTLY THE GND CREWS; WHEN WORKING ON THE ENG; SOMETIMES FAIL TO SECURE THE LATCHES IN ACCORDANCE WITH ANY SPECIFIED PROCS. THE RPTR STATED THAT AT LEAST 3 OTHER INCIDENTS OF LIKE KIND WERE RPTED TO HIM AS HE ASKED FELLOW CREW MEMBERS ABOUT THIS SIT. HE RPTED THIS TO HIS 'IN-HOUSE' UNION PLT REPRESENTATIVE BUT NOT TO THE COMPANY. IT WAS SUGGESTED TO THE RPTR THAT HE ASK THE UNION REPRESENTATIVE TO BRING THIS MATTER TO THE ATTN OF THE ACR.