A PIPER ARCHER IS FLOWN ON 2 TRAINING FLTS AFTER A SEAT REPAIR HAD NOT BEEN CORRECTED IN ACCORDANCE WITH THE AIRWORTHINESS REQUIREMENTS AT ZZZ; US.

Narrative

I WAS CALLED OUT TO AN ARCHER (PA28-181) TO CHK ON A COMPLAINT ABOUT THE COPLT'S SEAT. THE GAS CYLINDER THAT IS USED TO RAISE AND LOWER THE SEAT WAS LEAKING DOWN. AFTER APPRAISING THE SIT; I RETURNED TO THE HANGAR TO GET A NEW COPLT SEAT. AT THIS TIME I FOUND OUT THAT WE DID NOT HAVE A SPARE COPLT SEAT IN STOCK. I WENT BACK OUT TO THE ACFT AND INFORMED THE PLT THAT WE DID NOT HAVE A REPLACEMENT SEAT AVAILABLE; NOR DID WE HAVE ANY SPARE ACFT. AT THIS TIME WE TALKED ABOUT THE OPTIONS AND DECIDED TO USE A SPARE SEAT CUSHION TO ELEVATE THE COPLT; AND I SIGNED OFF THE TECH LOG AND THE WORK ORDER AS WAITING FOR PARTS (REPLACEMENT SEAT). AT NO TIME WAS THE STRUCTURE OF THE COPLT'S SEAT; OR ITS MOUNTING POINTS ALTERED. A SHORT WHILE LATER; I WAS INFORMED BY THE CHIEF INSPECTOR THAT THE WAY I SIGNED OFF THE DISCREPANCY WAS INCORRECT; AS WE DID HAVE A NEW GAS CYLINDER TO PROPERLY REPAIR THIS SEAT. IN MY HASTE TO GET THIS ACFT AIRBORNE; I HAD NOT CONSIDERED REPLACING THE GAS CYLINDER ITSELF; OR REMOVING A SEAT FROM ANOTHER ACFT AS A REPLACEMENT. I THEN WENT OVER TO OPS AND ASKED THEM TO GND THIS ACFT UPON ITS RETURN; SO THAT PROPER REPAIRS TO THE COPLT SEAT COULD BE MADE. SUPPLEMENTAL INFO FROM ACN 576787: MY TECHNICAL LOGBOOK ENTRY WAS -- R FRONT SEAT WILL NOT STAY UP; INOP. I ASKED IF THE WRITE-UP COULD BE CARRIED FORWARD? A SEAT CUSHION COULD GIVE ME THE EXTRA HT. WRITE-UP WAS SIGNED OFF AND STAMPED; SAFE FOR FLT. AFTER TKOF AND IN THE PRACTICE AREA; FLT OPS ASKED THAT I FINISH THE LESSONS AND RETURN THE ACFT TO MAINT. AFTER PARKING; MY FLT OPS MGR AND ASSISTANT CHIEF PLT; ASKED ME ABOUT THE SEAT WRITE-UP. THE FLT MAY HAVE BEEN SAFE; BUT NOT LEGAL. THE 'MER' WAS NOT FOLLOWED.