KSB-117-444
DATE: 2018-08-29
SERVICE BULLETIN Kawasaki BK117
TITLE: Inspection of the Brush Leads for the Starter-Generator
1. E FFECTIVITY
(1) Helicopters Affected:
Model Mfg. Serial No.
KAWASAKI-BK117, BK117 A-3, BK117 A-4,
All Helicopters
BK117 B-1, BK117 B-2, BK117 C-1
BK117 C-2 4001 - 4047
(2) Parts Affected:
Part No. Part Name Remarks
23032-020 (NOTE 1)
23032-022 (NOTE 2)
23032-048 (NOTE 2)
23032-049 (NOTE 1) Starter-Generator
23081-042 (NOTE 1)
23081-043 (NOTE 2)
23081-072 (NOTE 2)
(NOTE 3)
NOTE 1: Includes the star ter-gene ra tor an d the QAD k it.
NOTE 2: S tarter -gene rato r onl y.
NOTE 3: Pa rt numbers 23032-020 , 23032-022, 23032 -048, 23032 -049,
23081-042, 23081-04 3, and 23081-072 a re applied to the models tha t f ollow.
23032-020 or 23032-022: KAWASAKI-BK117, BK117 A-3, and BK117 A-4
23032-048 or 23032-049: KAWASAKI-BK117 B-1 and BK117 B-2
23081-042 or 23081-043: KAWASAKI-BK117 C-1 and BK117 C-2
23081-072 : KAWASAKI BK117 C-2
2. P URPOSE
On the KAWASAKI-BK117 C-2 helicopter, it was reported that the BAT DISCH caution indication
displayed due to a drop in generator voltage. This drop in generator voltage was caused by the
insulation sleeving of the brush leads catching on the edge of the brush holder and inhibiting
brush movement.
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KSB-117-444
This Service Bulletin provides the inspection procedure to check that the insulation sleeving of
the brush leads and/or brush leads of the start-generator are installed so as not to interfere with the
brush holder, and the procedure to re-work the brush lead formation as necessary.
This inspection will be incorporated into the next revision of the Maintenance Manual
(MM/AMM).
3. C ATEGORY
ESSENTIAL
4. COM PLIANCE
After receiving this Service Bulletin, the inspection must be accomplished in accordance with
section 9 of this Service Bulletin within 100 flight hours.
5. JC AB APP ROVAL
Approved by JCAB.
6. LOGBOOK ENTRY
Make an entry in the Aircraft Logbook stating that the work has been accomplished in accordance
with KSB-117-444.
7. M AN-HOUR REQUIRED
Approximately 5 man-hours (for reference only) will be required.
8. WE IGHT AND B AL ANCE CH ANGE
None.
9. ACCOM PLISHMENT INSTRUCTIONS
(1) Remove the starter-generator from the helicopter as follows.
[KAWASAKI-BK117, A-3 thru C-1]
a. Make sure that all electrical power supplies are OFF.
b. As necessary, remove the engine cowlings in accordance with section 22-11 of the
KAWASAKI BK117 MAINTENANCE MANUAL or section 22-11 of the KAWASAKI
BK117C MAINTENANCE MANUAL.
c. Remove the starter-generator in accordance with section 61-6 of the KAWASAKI BK117
MAINTENANCE MANUAL or section 61-6 of the KAWASAKI BK117C MAINTENANCE
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KSB-117-444
MANUAL.
[KAWASAKI-BK117 C-2]
Remove the starter-generator in accordance with paragraph 4-2, AMM 24-30-00.
(2) Remove the fan cover of the starter-generator.
(3) Inspect that the brush leads or the insulated sleevings of the brush leads are installed properly
so as not to interfere with the leading edges of the brush holder.
Inspection points and good and poor conditions (typical examples) are shown in Figure 1 and
Figure 2 respectively.
(4) If the brush leads or the insulated sleevings of the brush leads could interfere with the leading
edge of the brush holder, adjust the brush lead formation correctly in accordance with
Standard Practice Document 1006 of Safran Power USA. The applicable formation
procedures of Standard Practice Document 1006 of Safran Power USA are shown on
Attachment 1 through Attachment 3.
Starter-Generator Formation Procedure
23032-020 or 23032-022, and 23032-048 or
Attachment 1
23032-049
23081-042 or 23081-043 Attachment 2
23081-072 Attachment 3
(5) Install the fan cover of the starter-generator.
(6) Install the starter-generator on the helicopter as follows.
[KAWASAKI-BK117, A-3 thru C-1]
a. Install the starter-generator in accordance with section 61-7 of the KAWASAKI BK117
MAINTENANCE MANUAL or section 61-7 of the KAWASAKI BK117C MAINTENANCE
MANUAL.
b. As necessary, install the engine cowlings in accordance with section 22-13 of the
KAWASAKI BK117 MAINTENANCE MANUAL or section 22-13 of the KAWASAKI
BK117C MAINTENANCE MANUAL.
[KAWASAKI-BK117 C-2]
Install the starter-generator in accordance with paragraph 4-2, AMM 24-30-00.
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KSB-117-444
(7) Close Up
a. As necessary, clean up around the work area.
b. As necessary, connect the battery.
c. Complete this Service Bulletin by making an entry in the Aircraft Logbook stating that the
work has been accomplished in accordance with KSB-117-444.
10. PARTS AND M AT ERIAL INFORM ATION
(1) Required Parts for One Helicopter
None required.
(2) Required Materials for One Helicopter
None required.
(3) Parts to be Removed
None.
11. SPECIAL TOOLS RE QUIRED
None required.
12. REFERENCE TECHNICAL D ATA
KAWASAKI BK117 MAINTENANCE MANUAL (Excluding the BK117 C-1 and the BK117 C-2)
KAWASAKI BK117C MAINTENANCE MANUAL (BK117 C-1)
KAWASAKI BK117C-2 AIRCRAFT MAINTENANCE MANUAL (AMM)
SAFRAN Power USA Standard Practice Document 1006: 24-00-06
13. AVAIL AB ILIT Y OF KIT
The kit is not required for this Service Bulletin.
Prepared by: KAWASAKI HEAVY INDUSTRIES, LTD.
AEROSPACE SYSTEMS COMPANY
1, Kawasaki-cho, Kakamigahara City,
Gifu Prefecture, 504-8710, Japan
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KSB-117-444
The brush leads are separated so
as not to interfere with the fan
cover of the starter-generator.
The brush leads are positioned so
as not to interfere with the edge of
the brush holder when the brush is
worn away and the brush leads are
down into the brush holder.
Edge of Brush Holder
Figure 1 Brush Leads with Good Formation (Typical Example)
Brush Leads
(The brush leads are not separated.
The brush leads could interfere with
the edge of the brush holder.)
Edge of Brush Holder
Figure 2 Brush Leads with Poor Formation (Typical Example)
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KSB-117-444
Attachment 1 (1/1)
Brush Lead Formation Procedure for Starter-Generator 23032-020 or 23032-022, and 23032-048 or
23032-049
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KSB-117-444
Attachment 2 (1/2)
Brush Lead Formation Procedure for Starter-Generator 23081-042 or 23081-043
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Attachment 2 (2/2)
NOTE: Only the affected brush is shown.
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Attachment 3 (1/2)
Brush Lead Formation Procedure for Starter-Generator 23081-072
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Attachment 3 (2/2)
NOTE: Only the affected brush is shown.
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