Summary
We propose to adopt a new airworthiness directive (AD) for certain Air Tractor, Inc. Models AT-802 and AT-802A airplanes. This proposed AD would require you to repetitively inspect the attach angles on the firewall mounted hopper rinse tank shelf for damage and/or cracks and replace damaged and/or cracked attach angles. Replacing the attach angles with steel attach angles would terminate the proposed repetitive inspection requirement. Reports of an uncommanded change in the engine power setting caused by separation of the hopper rinse tank shelf from the firewall prompted this proposed AD. We are proposing this AD to detect and correct damage and/or cracks in the attach angles on the firewall mounted hopper rinse tank shelf, which could result in failure of the attach angles. This failure could lead to shelf movement under maneuver load and shifting of the engine power cables, which could result in an uncommanded engine power setting change.