*Stow solenoid
*Deploy solenoid
*Manual isolation (shutoff)valve.
The manual isolation valve handle has a hole for the T/R maintenance deactivation pin.
Training Information Point
You use the manual isolation valve handle to prevent accidental operation of T/Rs when persons or equipment are near the T/R.
You put in a lock pin to keep the handle in the shutoff position.
The T/R deactivation for maintenance is different than the T/R deactivation for airplane dispatch.Be sure to follow the airplane maintenance manual (AMM)procedures.
WARNING:
BEFORE YOU REMOVE THE LOCK PIN FROM THE T/R CONTROL VALVE MODULE FOR THE THRUST REVERSER,MAKE SURE THE THRUST REVERSER
SLEEVES ARE IN THE CORRECT POSITION.
IF THE THRUST REVERSER SLEEVES ARE IN THE STOWED POSITION,THE REVERSE THRUST LEVER MUST BE FULLY FORWARD.
IF THE THRUST REVERSER SLEEVES ARE IN THE DEPLOYED POSITION,THE REVERSE THRUST LEVER MUST NOT BE IN THE STOWED POSITION.
IF THE POSITION OF THE REVERSE THRUST LEVER DOES NOT AGREE WITH THE POSITION OF THE THRUST REVERSER SLEEVES, THE THRUST REVERSER SLEEVES COULD MOVE WHEN THE HYDRAULIC SYSTEM IS ACTIVATED.
THIS COULD CAUSE INJURY TO PERSONS AND DAMAGE TO EQUIPMENT.
(3)飞行员收回反推的操作程序
故障现象:飞机降落打开反推后无法收回或者反推故障灯点亮,反推手柄在反推慢车位和收回位之间。
以下描述了当反推手柄在某个特殊位置的情况:
- 如果反推手柄在从反推慢车位向收回位两个球的位置时,将激励EAU的BITE检查反推是否在8秒钟内收回。
- 如果反推手柄再向前一个球(从反推慢车位向收回位三个球),EEC的BITE检查不使用前推力,直到反推完全收回(10秒延时器)。
- 如果反推手柄位于从反推慢车位向前四个球的位置,反推将收回。
如果反推手柄在从反推慢车位向前两个球到三个球的区间停留时间较长,上述的一个或以上的BITE将不能通过,从而导致EAU或EEC的故障指示。如果反推手柄在该区间提留超过16秒,同步锁将锁定,反推将停留在原位直到反推手柄通过循环复位。
如果ENG CONTROL灯点亮,必须检查FMC-CDU EEC当前故障,确认属于ENGINE CONTROL LIGHT级别的故障代码只有78-31521 (engine No. 1)和78-31522 (engine No. 2)。另外,如果EEC的通道交换数据链不工作,以下的故障代码可能以任意的组合方式出现:
78-11521 (ENG 1) 78-11522 (ENG 2)
78-21521 (ENG 1) 78-21522 (ENG 2)
73-10101 (ENG 1) 73-20102 (ENG 2)
如果确认了只有以上的EEC故障代码出现,可以通过多次收放来重置反推故障灯。
NOTE: 为避免出现以上故障出现,反推手柄应该避免停留在反推慢车位和收回位之间,。通常情况下,从反推慢车位置到收回位置(或反向)的运动不应该超过3秒钟。BOEING曾经颁发Flight Operation Technical Bulletin 99-3 描述了该问题。
EAU的功能
The engine accessory unit (EAU)has these functions:
*Controls the thrust reverser (T/R)auto-restow operation
*Helps you do trouble-shooting of the T/R control system
*Controls the REVERSER lights on the P5 aft overhead panel in the flight compartment.
反推灯亮的几个条件
A REVERSER light comes on when any of these conditions happen:
*For 10.5 seconds after T/R stow command
*T/R stow control system component fault (except during a deploy operation)
*T/R deploy control system component fault during deploy operation.
The engine accessory unit (EAU)contains the logic necessary to identify T/R control system component faults.The EAU controls the REVERSER lights.
The EAU identifies any of these conditions as a stow fault:
*Any sleeve stow sensor is near (10s after stow command)
*Any sleeve lock sensor is near (10s after stow command)
*Left or right sync lock voltage (26s after stow command)
*Directional control valve (DCV)sensor near (15s after stow command)
*HIV sensor near (15s after stow command).
For any of these conditions the REVERSER light comes on.The light goes out when the stow fault goes away.The master caution and the ENG annunciator come on if the fault stays for
more than 13 seconds.
The REVERSER light will come on and stay on (latch)if the EAU sees the arm switch fail to the deploy position.This is the only stow fault that keeps the REVERSER light on.You must replace the switch,deploy the T/R and reset the EAU to make the REVERSER light go out.
The EAU identifies any of these conditions as a deploy fault:
*Any sleeve stow sensor far (6s after deploy command)
*Any sleeve lock sensor far (6s after deploy command)
*No left or right sync lock voltage (2s after deploy command)
*Directional control valve (DCV)sensor far (6s after deploy command)
*HIV sensor far (6s after deploy command).
For any of these conditions the REVERSER light comes on.The master caution and the ENG annunciator comes on if the fault stays for more than 13 seconds.
A deploy fault keeps the reverser light on.You must fix the problem which causes the fault,deploy the T/R,and clear (reset)the EAU deploy fault memory before the reverser light
can go out.
(4)传感器接头线路问题
故障现象:
飞行中REVERSER灯点亮,通常以下之一的EAU故障灯也点亮:
S831 L SLEEVE STOWSENSOR
S835 L SLEEVE LOCK SENSOR
S832 R SLEEVE STOWSENSOR
S836 R SLEEVE LOCK SENSOR
S833 HYD ISO VALVE SENSOR
S833 HYD ISO VALVE SENSOR 点亮是由于以上四个故障之一激励了反推自动收回系统。
由于以下机体-机翼、吊架-机翼间的过渡电接头的瞬间问题导致了此故障:
NOTE: 这些电接头位于机体-机翼、吊架-机翼的结合面,通常是因为接头的污染引起的。通常检查、分离后重新安装可以解决问题。某些情况下,电接头可能需要更换。
小结
当发现反推系统的故障时,需要详细的描述以充分了解现象和帮助排故。这对于反推系统特别重要,因为反推系统的故障非常多样化。然后按照FIM的指导结合以上的信息来排故。
另外很重要的一点,EAU的故障代码对排故也是很关键的。EAU的故障代码可以通过5次收放反推来清除,但是这仅仅清除了故障代码,并没有排除故障,故障可能在下一个航段后又会出现。