Bell 429 - Conditional Inspections - Compressor Stall or Surge; Table 1. Conditional Inspections - Compressor Stall or Surge

BHT-429-MPI
ConditionalInspections-CompressorStallorSurge
Table1.ConditionalInspections-CompressorStallorSurge
INITIAL
DATAREFERENCEINSPECTIONTASKDESCRIPTION
MECHOTHER
DATE:
W.O.
FACILITY:
HELICOPTERS/N:
REGISTRYNO.:
TOTALTIME:
SIGNATURE:
NOTE
Iftheinformationcontainedinthefollowingconditionalinspection
doesnotfullyreecttheoccurrenceorifadditionalinformationor
claricationisrequired,pleasecontactProductSupportEngineer-
ingforassistance.
Anenginecompressorstallorsurgeisarumbleoraseriesofpops
and/orsevereenginevibrationswithanassociatedrapidrisein
MeasuredGasT emperature(MGT).
Thecompressorstallmaycauseseveretorsionalloadingofthemain
driveshaft.Thetorsionalloadingcancausescoringofthetransmission
inputgearsanddamagethemaindriveshafts.Thetailrotorgearbox
attachmentttingmaybedistortedordamaged.
Ifacompressorstallorsurgeisreportedand/orsuspected,dothe
followinginspections:
429-MM,Chapter71POWERPLANT
1.VisuallyexaminetheinletForeignObjectDamage(FOD)screenor
theinletbarrierlter(ifinstalled)forblockage.
2.Visuallyexaminethecentrifugalcompressorbladesforaccumulation
ofdirt,erosion,orFOD.
PW207D1/D2MM
(P/N3071602)
a.Ifthecentrifugalcompressoriscontaminated,doanengine
compressorwashandapowerassurancecheck.
b.IftheerosionorFODismorethanthepermittedlimits,doateardown
inspection.
3.Ifthepreviousstepsdonotdeterminethecauseofthestallorsurge,
visuallyexaminethepowerturbineassembly.
429-MM,Chapter63MAINROTORDRIVESYSTEM
1.Doaninspectionofeachengine-to-transmissiondriveshaftasfollows:
a.Examinetheengine-to-transmissiondriveshaftforconditionand
securityofattachment.
b.Ifanydamageisfoundontheengine-to-transmissiondriveshaft,
removeanddiscardthedriveshaft.
c.Ifnodamageisfoundontheengine-to-transmissiondriveshaft,the
driveshaftisserviceable.
2.Visuallyexaminethechipdetectorsofthetransmissionassemblyand
tailrotorgearboxforcontamination.
429-MM,Chapter63
429-MM,Chapter65
a.Ifthereareunwantedparticlesonachipdetector,removethe
transmissionassemblyorthetailrotorgearbox,asapplicable.
Applicableto:ALL429-A-05-50-00-07A-284A-A
ECCNEAR99
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