What was found
DURING DEPARTURE FROM TUCSON INTERNATIONAL AIRPORT, (KTUS) IN N567MC FEB 8, 2026 AT 0900 LOCAL TIME, WHILE CLIMBING THROUGH APPROXIMATELY 23,000 FEET MSL, A LOUD AND ABNORMAL WHISTLING NOISE WAS NOTED FROM THE MAIN CABIN DOOR SEAL AREA. AIRCRAFT PRESSURIZATION INDICATIONS REMAINED STABLE AND WITHIN NORMAL LIMITS, WITH NO ABNORMAL CABIN ALTITUDE OR RATE OF CLIMB OBSERVED. THE DECISION WAS MADE TO DISCONTINUE THE CLIMB AND RETURN TO TUCSON. AIR TRAFFIC CONTROL WAS ADVISED, AND VECTORS WERE REQUESTED BACK TO TUS. THE RETURN WAS CONDUCTED AS A NON-EMERGENCY. THE AIRCRAFT LANDED WITHOUT INCIDENT AND FURTHER EVALUATION WAS CONDUCTED WITH THE DIRECTOR OF MAINTENANCE. FURTHER MAINTENACE INSPECTION OF MAIN ENTRANCE DOOR SEAL, FOUND DEBRIS LODGED BETWEEN INFLATABLE DOOR SEAL AND AIRFRAME.REMOVED DEBRIS AND AIRCRAFT DEPARTED WITHOUT ANY AIR LEAKS. THE DEBRIS WAS LOCATED UNDER THE FINAL STEP COVER WHEN STEPPING INTO THE CABIN.