What happened
On an Embraer 190-100 IGW, registration YV2966, operated by CONVIASA, a flight was underway from Maiquetía International Airport to José Tadeo Monagas International Airport in Maturín. The aircraft was carrying 77 people, including 70 passengers and 7 crew members, including technical staff.
During the approach phase to Maturín at 13:16 UTC, while flying at 3,000 feet, the flight crew attempted to configure the aircraft for landing by selecting flap position 03. During this process, the Engine Indicating and Crew Alerting System (EICAS) displayed a "SLAT-FLAP LEVEL DISAG" message. This failure prevented the crew from extending the flaps to position 02.
Following established Quick Reference Handbook (QRH) procedures, the pilot in command canceled the approach. The crew requested authorization for a holding pattern at the MEREY position to attempt to troubleshoot the flap configuration. While testing the movement between positions 0 and 02, the crew confirmed that the flaps would not extend to position 03. Due to the limited runway length at Maturín compared to Maiquetía, the pilot decided to return to the origin airport. The aircraft landed safely at Maiquetía at 13:54 UTC with no injuries to the passengers or crew.
The investigation
The JIAAC investigation included interviews with the flight crew and a review of various operational documents, including licenses, maintenance logs, and flight plans. Investigators also examined the aircraft's airworthiness certificates and maintenance records from the operator's maintenance organization (OMAC-N 431).
A joint inspection was conducted between the JIAAC and the airline's maintenance technicians to perform a fault isolation process according to the manufacturer's maintenance manual. The inspection focused on the root cause of the slat-flap asymmetry error.
Findings
- The investigation identified the malfunction of the SLAT POSITION SNSR UNIT as the primary cause of the incident.
- A contributing factor was the degradation of this component prior to its scheduled maintenance inspection interval.
- Environmental conditions, specifically high humidity exposure, were identified as a contributing factor to the component's premature degradation.