波音737飞机收起落架导致备用泵低压灯亮

HNAT737技术问题说明提示单编号撰写校定批准日期TIP737-2020-29-002张桃赵斌曾品/2020.2.12标题收起落架导致备用泵低压灯亮一、适用性737二、背景描述某日1架737NG飞机，机组落地后反映了一个奇怪的故障现象：收起落架时备用液压低压灯亮，后恢复正常。众所周知，收起落架使用A系统，和备用液压系统并无直接关系，特做一说明。三、解释说明1,由于故障时间短，机组没有观察到其他现象，所以还是上译码吧：HYDRAULI HYDRAULLEFTAIR/GROC OIL IC OILGEARNOSERIGHT LEFTNOSERIGHT EYD OIL HYD OIL EYDHYDDUNDOT STS OTY SISIDOFNGE成CEARCEAR RED CEAR RED CEAR RED PRESSUR PRESSUR STS A SYS BHYD SYS ETD STSA ELECSTANDBTDONNDONN VARNARN WARN E SYS A E STS B ENG#1 ELECRNG#2BGONL0:21-53G0UWDDOVNIDOVNDOMN NO VARN O VARS NO VARN3056 MORLAL ORMAL 9ORMAL NORYALTORMAL0:21:54G0UwD107.2500厚指NDO NO YAKN BO FARB NO YARNHOGAL ORHAL ORNAL NCRMALBORIAL0:21药G0wDB6 DOVNDONN NO VARN SO WARN NO TARN30弱N05 MAL SORMAL。ORMAL,NORA1RORHAL0:215641R00NDONN NO WARN NO WARN NO WARN 3052NOGMAL SORMAL MORMAL NORMALNORMAL0:24:57A1R00号信DOTNDONN NO TARN SO FARN NO TARN3006 NOGMAL SORMAL WORMAL NORIALSORMAL0:2151B10775100DQMK HO VARN NO WARK NO WARN S0520项AL ORMAL BORMAL NOB4LOORHAL0:24:591R86D0H10WDONN NO VARN SO FARN NO FARN3066 NOGMAL SORMAL WORMAL NORMAL5O求AL0:22400A1R0情ARKARH厚A月程INOGMAL FORMALWORMAL NORALMORMAL0:22:01A1R02PARNFAKNARN3056 NORMAL NORMAL WORMAL NORMALLO PRESS0:22402A1R101UPUPARNTARN厘AR霞224NORHAL MORMAL MORMAL LO PRESS MORMAL0:22-03A1R86UPPMARKV4YHAR3056 NORMAL MORMAL ORMAL WORMALMORMAL0:22:041RUPveUPFARN年人RN厘AR52092NOGMAL SORMAL MORMALINOBMALBO求IAL0:22a051RLARARHUARSOORUAL0:22:06A1R05.2PWARNFARNFARN258NORMAL NORMAL MORMAL NORMALNORMAL0:22:07A1R86 UPUPARN冒ARNFARN3062 NOGMAL MORMAL WORHAL NORTAL.SORMAL0:22-00A1RPNO WARN SO WARN NO WARNNORMAL SORMAL WORMAL HORMALNORMAL0:22=09A1克UPNO YARN SO FAR5NDTA家H3043SC5IALO求慧AL MORMAL NORMALO皮"AL0:22410TR8525UPUPNO VARN NO VABN NO VARN012INORMAL ISORMAL ORMAL INORMALBORMAL0:22:111求E即NO WARN SO WARN NO WARN3048 NOGMAL BORMAL MORMAL NORMALO业机AL0:22:12ATR妒岖NO VARN NO WARN NO WARNNOGMAL MORMAL.MORMAL NORWALRORMAL通过对数据的解析，我们发现了更多的特征：A系统EMDP和备用泵均出现一秒低压警告，A系统最低压力2092PSl。为什么会出现这一情况，我们从故障表象来一步步推导。2故障分析2.1备用泵低压灯亮正常情况下备用泵不工作，低压灯处于熄灭状态，当满足以下任一条件，并且备用泵输出压力不足1300PSl,低压电门接通导致低压灯亮：A任意一个飞控电门在备用方向舵位：B.自动备用系统继电器工作：C.备用襟翼预位电门放到ARM位。这也表明备用泵真实自动工作了，泵为什么会工作呢？2.2备用泵自动工作备用泵自动工作，需要满足以下所有条件1.任一飞控A或B电门在ON位：2.备用襟翼预位电门在OFF位：1/3