Dc10hound From United States of America, joined Dec 2000, 463 posts, RR: 5
Reply 10, posted (12 years 7 months 3 weeks 4 hours ago) and read 2279 times:
Mr Boeing sez:
"Each flight control low pressure light monitors the position of the standby rudder shutoff valve when the flight control switch is in the STDBY RUD position."
"When the flight control switch is in the STDBY RUD position, the low pressure warning switch is not connected to the low pressure light. When the standby rudder shutoff valve is in the closed position, the valve position relay provides a ground to the low pressure light. When the standby rudder shutoff valve moves to the open position, the valve position relay energizes and removes the ground to the low pressure light."
"Eagles soar. But weasels never get sucked into jet intakes.."
Cdfmxtech From United States of America, joined Jul 2000, 1341 posts, RR: 24
Reply 11, posted (12 years 7 months 3 weeks 3 hours ago) and read 2263 times:
The question is with the Flight Controls System "A" switch in the normal position, which is "A" ON.
OK, the answer:
Post AD 97-14-03 (Yaw Damper System Modification) which was due for completion in 2000
The Yaw Damper Coupler can turn the System "A" light ON in the even that pressure to the Main Rudder PCU is less than 500 psi or when full pressure is commanded to the RPR and system pressure is less than 2,200 psi.
If you want to see what Mr. Boeing sez about this, Ref AMM 22-12-01