Incident Description
On February 1, 2012, an Embraer E170-200 aircraft departed from Warsaw Chopin Airport (EPWA). After liftoff, the flight crew was unable to move the landing gear lever to the "UP" position. The Engine Indication and Crew Alerting System (EICAS) did not display any fault messages. The crew decided to return to the departure airport and performed a landing without further issues.
Investigation and Findings
The aircraft was handed over to technical services for inspection. Ground tests of the landing gear system were conducted. Following the troubleshooting procedure, it was determined that the Weight-on-Wheels (WOW) sensors on the right main landing gear were faulty. The sensors were replaced in accordance with Aircraft Maintenance Manual (AMM) task 32-62-03-400-801A. After the repair, the aircraft returned to service.
Probable Cause
The probable cause of the incident was a malfunction of the WOW sensors on the right main landing gear.
Follow-up Actions
The operator's technical services performed the inspection and replaced the defective WOW sensors. No safety recommendations were issued by the investigating authority.