What happened
On 26 February 2003, a Cessna 402B, registered as ZS-ORF, was performing a ferry flight from Wonderboom aerodrome to Grand Central aerodrome. The aircraft was being operated by Coin International. As the aircraft was rotating on Runway 11, the emergency exit hatch on the right side of the fuselage unexpectedly opened and became detached from the airframe.
Despite the loss of the hatch, the pilot managed to maintain control of the aircraft and completed the takeoff. The aircraft subsequently returned to the aerodrome and performed a safe landing on Runway 24. The detached hatch landed near the intersection of Runways 11 and 24, sustaining only minor damage.
The investigation
Investigators examined the aircraft's closing and locking mechanisms to determine why the hatch had failed. The inspection confirmed that there were no mechanical failures within the locking hardware itself. However, the investigation focused on the position of the locking pin. It was determined that the pin had either migrated from its intended position over time or had been partially disengaged by the emergency handle being pulled.
While the pilot noted that the emergency handle appeared to be in its usual position and had been consistent during previous flights, the physical separation of the hatch indicated the pin was not fully secured. Maintenance records showed the aircraft had undergone its last maintenance inspection (MPI) on 5 December 2002, with only 30.7 flying hours accumulated since that check.