What happened
On September 10, 2013, an Embraer E170-100 was performing a climb from Gdańsk (EPGD) when the crew received two simultaneous warnings: FLAP LO RATE and ADS 1 HTR FAIL. Following these indications, the crew decided to abort the flight and return to Warsaw (WAW). The aircraft landed safely in Warsaw using the correct landing configuration, and the aircraft was subsequently handed over to maintenance crews.
The investigation
Maintenance personnel performed both mechanical and electrical rigging of the flap system in accordance with the Aircraft Maintenance Manual (AMM). Following these adjustments, system tests were conducted, which initially showed the flaps were operating correctly. A technical test flight was performed on September 13, 2013, to verify the repairs.
During this test flight, the ADS HTR FAIL warning recurred, although the ground tests had not replicated the issue. To resolve this persistent fault, the Air Data Smart Probe No. 2 was replaced according to the manufacturer's instructions.
Findings
- The primary cause of the incident was the unintended misalignment of the flap system.
- The ADS 1 HTR FAIL indication was a secondary issue that persisted through initial ground testing but was resolved via component replacement.