EMB ERJ 145 ER/LR
Flight Crew Air Transport Pilot (ATP)
Communication Breakdown; Troubleshooting
Aircraft Equipment Problem Critical
Flight Crew Landed in Emergency Condition
Aircraft; Human Factors
During cross wind flare; landing and roll out; rudder became very stiff. During roll out; we received a Rudder 1-2 Inoperative (Inop) message; Manual Reversion. At Gate; System reset per Maintenance Control; Operational checks 'good.' This is the 4th 'Rudder 1-2 Inop' on four different Embraer 145 aircraft I have experienced in as many weeks. It is the 5th one I'm aware of. Four weeks; five aircraft; five  Rudder 1-2 Inops.
Reporter stated he has experienced three incidents on three different EMB-145 aircraft of rudder stiffness on the ground after pushbacks; before taxiing out; when they were checking Hydraulic Systems and performing rudder full travel checks. Each time they would receive an EICAS Rudder 1-2 Inop message; Manual Reversion. The other two incidents have been in flight and on landing. There is a difference in the way the rudder stiffness develops when on the ground compared to in flight. On the ground; an immediate cutout of both hydraulic actuators (PCUs) seems to occur along with rudder stiffness and the EICAS Rudder 1-2 Inop; Manual Reversion message. In flight the stiffness is slower to occur; as if one and than the other rudder hydraulic actuator cuts out with the same EICAS message and Master Caution annunciation. Since he submitted his report he has had two more incidents of rudder stiffness in flight with the Rudder 1-2 Inop; Manual Reversion messages. He has had seven incidents in approximately two months time on different EMB-145 aircraft.Reporter stated he does not believe the AUTOMATIC SHUTOFF through the Speed Switch System; or the Rudder Hardover Protection System; nor the Spring-Loaded Cartridges below the rudder pedals are involved with the incidents. All the incidents have occurred with the Yaw Damper 'Not' engaged. He believes that currently the only common link appears to be the Rudder hydraulic actuators; which have been changed in the past. Although flying in Manual Reversion requires a lot more physical effort and the rudder response is much slower; the real concerns are when an engine failure develops or an uncommanded nose steering occurs that displaces the aircraft off centerline causing a runway excursion. He has been flying the EMB-145s for over eight years. He has not heard anything from Maintenance or Engineering about possible fixes. He suspects the number of incidents is more frequent than what is being reported.
Pilot reports he has experienced seven incidents of rudder stiffness on landing and prior to departure taxi-out; followed by an EICAS Rudder 1-2 Inop; Manual Reversion message and Master Caution annunciation on EMB-145 aircraft. Concerns raised that slowness in rudder response in Manual Reversion could affect controllability with an engine loss or uncommanded nose steering excursion on landing.