What actually happened !!
This in addition to my post regarding the Emergency Landing of Royal Nepal B-757 in kathmandu. Here is the actual copy of the Aircraft Tech. Log book. BTW The crew are still grounded by the F/O Operations Director till date.
Before the Flight (As logged by the Engineer)
1. C IRU INOP & ADD 11001 Raised & Released on MEL 34-21-1 C of C.
After the Emergency ( As Logged by the Cockpit crews)
“Just after Take Off aircraft HSI route went blank with FD, VOR, NDB, A/T, Yaw Damper, FMC, ADF, Autobrk not functioning. Landed back in Kathmandu with the only reference to Magnetic Compass.”
(MCDP Readings):
A/P DISC.
IRU C/FCC C;
A/P DISC
IRU L
A/P DISC
IRU R
A/P CTN
MODE ERR:
After the maintenance work was done (As Logged by Engineers in the Logbook)
1. L FMC replaced due route data not displayed on EHSI in map mode database updated. Ref TLP 108675 for FMS. FMS ops chkd satis. IRU ops chkd, Align lights flashing on all positioins aft present position reinserted 3 times, now satis, L IRU replaced as a precaution, all IRU operation checked satis. RDMI indication normal. Yaw Damper test Satis. Auto brake bit shows L IRU, RE L IRU replaced & Autobrake satis.
MCDP test shows L & R IRU/FCC test 01, satis. FMC test 10 Satis. test 30 Satis.
2. Over diffected Nav system’s indication & test normal.
3. CTR IRU SWAPPED WITH R IRU Defect remains. Returned to original position co-ordinates re entered 3 times, now OK FLT evaluatioin RA 409/410 date satis. cleared.
Any ideas & comments experts ?