Simrad SX90 - INSTALLATION REV C - Page 150

SimradSX90
thishighnoiseleveliscausedbyownoisefromthevessel’s
hullorbytheengine/propeller,performthefollowingtest.By
comparingthesethreeresultingplotsitshouldbepossibletosort
outifthemainnoiseiscausedbyownoiseorengine/propeller
noise.Ifthemainnoiseiscausedbyownoise,theship’shull
shouldbethoroughlyinspectedduringnextdocking.Ifthenoise
iscausedbytheenginepropeller,ensurethatthepropelleris
notchippedorcorroded.
1Enterthenoiselevelfor0degreesbearingfromtheNoise
measurementstableintothecolumnforStablespeedinthe
Noisevericationtable.
2From0knots,givefullenginethrust,andmakearead-outof
thenoiselevelforaccelerationwhenthevesselreacheseach
ofthelistedspeeds.Entertheresultsintothetable.
3Fromfullspeed,reducetheenginethrustforminimum
speed,andrecordsimilarresultsforretardation.
4Makeadashedlineplotoftheaccelerationnoiseintothe
Noise/speedplot,andadottedlinefortheretardationnoise.
Testresults
Thetablesandplotcreatedforthetestresultsareprovidedbelow.
Table11Noisemeasurements
Bearing
Speed—120°—60°0°+60°+120°+180°
0knots
2knots
4knots
6knots
8knots
10knots
12knots
14knots
16knots
148
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