B737 Undifferentiated or Other Model
Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 175; Flight Crew Type 18000
Communication Breakdown
Aircraft Equipment Problem Critical; Deviation / Discrepancy - Procedural Published Material / Policy
General Maintenance Action; General Flight Cancelled / Delayed
Aircraft; Company Policy; Human Factors; Manuals
During morning preflight; I regularly check the Standby Rudder; even though it's no longer in the preflight duties; it is the way I was taught to do my flow. Old habits are hard to break. On this particular day the Standby Rudder Test failed.  My question is: Why is this no longer a required test? This problem would have gone undetected without this test and could possibly have had much greater consequences if it was not discovered until it was needed. Up to and including catastrophic hull loss with Passengers onboard. I understand not wanting to 'wear it out' testing it; but; the Standby Rudder is very important and since the Low Pressure switch is de-activated until it is used; it would go undetected if not tested. There is an old saying: 'Use it or lose it'. Are we risking an important backup emergency system not working due to lack of use now?  [Recommend] This system needs to be tested regularly; if not by the Pilots then at least routinely by Maintenance.
Captain reports that a B737 aircraft in service at a gate; had failed a Standby Rudder Hydraulic Check and questions why the test is no longer required for Flight crews. Although the test has been removed from their preflight duties; he regularly checks the Standby Rudder and notes the problem would have gone undetected with possible greater consequences if it was not discovered until it was needed.