# AgustaWestland Bollettino Tecnico 412-133: No revision named

- Rights: © Leonardo S.p.A. Filed by the FAA in regulations.gov docket FAA-2012-0927; AD 2012-18-02 incorporates this document by reference. Not covered by OpenAirDocs’ CC0 dedication.
- Document: [AgustaWestland Bollettino Tecnico 412-133](https://openairdocs.org/service-documents/leonardo/sb-412-133.md)
- Title as filed: U.S. DOT/FAA - Agusta BT 412-133
- Pages: 9
- PDF: https://openairdocs.org/files/sha256/73/e4/73e4ecfe319893f481af4bec1b182da2c1ec39fd8ad61d8a0cc9c27845640742
- Page: https://openairdocs.org/service-documents/leonardo/sb-412-133/file/73e4ecfe3198

## Text

Each page's text from the PDF; open the PDF at a page with #page=N.

### Page 1

ALERT 
Page 1 of 8 
 
 
BOLLETTINO TECNICO 
The technical content of this document is approved 
under the authority of DOA nr. EASA.21J.005. 
N°          412-133 
DATE        May 17, 2012    
 
REV.
 
Compliance with 
this bulletin is: 
 
  
 
SUBJECT: HOIST HOOK ASSEMBLY P/N BL-5740-8, INSPECTION OF. 
 
REASON:  To avoid loss of hoist hook assembly P/N BL-5740- 8 installed on hoist P/N BL-
20200-75 (Breeze Eastern) and/or hoist P/N BL-20200-95 (Breeze Eastern).  
 
HELICOPTERS AFFECTED: 
Agusta AB412 and AB412EP helicopters. 
  
COMPLIANCE: 
Before next flight after receipt of this Bollettino , and subsequently every time the hook 
assembly is disassembled/reassembled. 
 
DESCRIPTION: 
It is reported to Agusta a case of separation of Ho ok P/N HK-118-2. The investigation 
performed revealed that the nut P/N BL-10892 and ho using hook P/N BL-9197 were not 
properly screwed (ref. Figure 1). In this condition  the two locking screws were not inserted 
into the slot located on the housing. Due to the similarity between the locking systems used on 
Hook P/N HK-118-2 and Hook P/N BL-5740-8, installed  on hoist P/N BL-20200-75 and/or 
hoist P/N BL-20200-95, this Bollettino provide the instructions to verify that the nut and body 
are properly screwed. 
MANDATORY
An appropriate entry should be made in the aircraft log book upon accomplishment.
If ownership of aircraft has changed, please, forward to new owner.
AgustaWestland S.p.A
Via Giovanni Agusta, 520
21017 Cascina Costa di Samarate (VA) Italy
Tel.: +39 0331 229111 - Fax: +39 0331 229605/222595
ALERT
ALERT

### Page 2

B.T. 412-133 
Page 2 of 8 
 
 
MANPOWER REQUIRED:   
Approximately 0,5 man-hour is required to carry out the visual inspection. 
WARRANTY:    N.A. 
MATERIAL REQUIRED:    
 
P/N  DENOMINATION  Q.TY  
MS-24665-88 (*) Cotter pin 2 
Note: (*) Required only if it is necessary disassembly/reassembly the hook assembly 
 
SPECIAL TOOLS:   N.A. 
WEIGHT AND BALANCE CHANGE:  N.A. 
REFERENCES:   
AB412-IPC  Illustrated Parts Catalogue 
AB412EP-IPC  Illustrated Parts Catalogue 
AB412-MM  Maintenance Manual 
TD-96-012  Breeze Eastern Operation and Maintenance  Manual  
PUBBLICATIONS AFFECTED:    
AB412-MPM  Maintenance Planning Manual 
ACCOMPLISHMENT INSTRUCTIONS:  
1.  Prepare helicopter for safe ground maintenance. 
2.  Reel out cable from hoist as required to allow the maintenance of the hook.  
3.  Disconnect battery and all the electric power source and/or the external power supply. 
4.  Pull down the rubber bumper (10) to get the visual of the set screw in the slot as illustrated in 
Figure 2.  
a.  If two screws (15) are inserted in the slots (ref. Figure 2), this indicates that nut and 
body are properly screwed. Check that rubber bumper  (10) return in proper position.   
No other action is required, proceed in accordance with  step 19. 
b.  If  two screws (15) are not inserted in the slots ( ref. Figure 3), this indicates that nut and 
the body are not screwed. In this case proceed in accordance with following steps 5÷18. 
5.  With reference Figure 4 separate the bumper assembl y from the hook assembly. Pull bumper 
assembly from top of sleeve (13) then slide it up wire rope cable toward the hoist assembly. 
6.  Remove cotter pins (16) and locking screws (15) from nut (14).

### Page 3

B.T. 412-133 
Page 3 of 8 
7.  While holding body (3), unthread nut (14), remove b ottom half of hook assembly and rubber 
bumper (10). Slide nut (14) and sleeve (13) up wire  rope cable away from the ball end to 
expose terminal clamp (11). 
8.  Remove ring (18) from terminal clamp (11) and then remove terminal clamp (11), sleeve (13) 
and nut (14). 
9.  With reference Figure 4 and 5 reinstall nut (14), s leeve (13) with terminal clamp (11), onto 
ball end of hoist cable, and secure terminal clamp with ring (18).  
10.  Slide sleeve (13) and nut (14) down until terminal clamp (11) seats in sleeve (13). In 
accordance with Figure 5 verify that terminal clamp  (11) and ring (18) are correctly seats in 
sleeve (13). 
11.  Install rubber bumper onto body (3). Thread body (3) with bottom half of hook assembly onto 
nut (14), until bottomed. 
12.  Back off nut (14) to line holes with next nearest s lots in body (3). Insert locking screws (15) 
and screw home to bottom of slot in body (3), and t hen secure locking screw in place with 
new cotter pins (16) P/N MS-24665-88. 
13.  Slide bumper assembly down and seats in sleeve (13). 
14.  Restore the power to the hoist, and proceed in accordance with following steps. 
15.  Run hoist to slowly pay out cable until the hook can be connected to a weight of 272 Kg. 
16.  Connect load to hook and slowly reel cable in until the weight is lifted off the ground 
17.  Once weight is off the ground, lower weight back to the ground and remove the weight. 
18.  Pull down the rubber bumper (10) to get visual of t he set screw in the slot as illustrated in 
Figure 2. 
a.  If two screws (15) are inserted in the slots (ref. Figure 2), this indicates that nut and 
body are properly screwed. Check that rubber bumper  (10) return in proper position.   
No other action is required, proceed in accordance with step 20. 
b.  If two screws (15) are not inserted in the slots (r ef. Figure 3), this indicates that nut and 
the body are not screwed, in this case disconnect t he power to the hoist, and repeat steps 
5÷18. 
19.  Reconnect battery and all the electric power source and/or the external power supply. 
20.  Run hoist to the full in position to secure to hook and bumper assembly on hoist. 
21.  Return the helicopter to flight status and annotate  records to indicate compliance with this 
Bollettino.

### Page 4

B.T. 412-133 
Page 4 of 8 
 
 
 
 
 
 
Figure 1 – HK-118-2 Hook assembly (For reference only) 
 
 
NUT P/N BL-10892 
HOUSING HOOK  
P/N BL-9197

### Page 5

B.T. 412-133 
Page 5 of 8 
 
 
 
 
 
 
 
 
Figure 2 – Detail of Hook assembly P/N BL-5740-8 
This condition indicated that nut and body are screwed. 
The locking screws P/N BL-9920 are properly inserted in the slot. 
 
 
 
 
 
 
SCREW INSERTED 
IN THE SLOT 
NUT (14) 
BODY (3) 
RUBBER BUMPER (10)

### Page 6

B.T. 412-133 
Page 6 of 8 
 
 
Figure 3 – Detail of hook assembly P/N BL-5740-8 (Cotter pin omitted) 
This condition indicated that nut and body are not screwed 
Locking screws P/N BL-9920 not inserted in the slot. 
 
 
 
SCREW NOT INSERTED 
IN THE SLOT 
NUT (14) 
BODY (3)

### Page 7

B.T. 412-133 
Page 7 of 8 
 
 
NOTE: Bumper assembly not illustrated 
 
Figure 4 – BL-5740-8 Hook assembly 
 
WIRE ROPE ASSEMBLY  
SWIVEL HOOK   (1)  
SPACER (17)  
BODY (3)  
WASHER (4)  
BEARING (5)  
WASHER (19)  
RUBBER BUMPER (10)  
SCREW (15)  
COTTER PIN (16)  
TERMINAL CLAMP (11)  
RETAINING RING (18) 
LABEL (12)  
NUT (14) 
PIN-SPRING (9)  
NUT (8)  
PACKING (6) 
RETAINER BEARING (7)  
SLEEVE (13)  
BEARING (2)

### Page 8

B.T. 412-133 
Page 8 of 8 
 
 
 
 
 
 
 
Figure 5 – Detail of terminal clamp installation 
 
 
 
HOIST CABLE 
SLEEVE (13) 
RING (18) 
TERMINAL CLAMP (11)

### Page 9

Note: 
Remarks: 
Informazioni: 
Information: 
 
Al fine di gestire le varianti alla configurazione base, in relazione all’emissione de l Bollettino Tecnico, preghiamo di voler compilare il presen-
te modulo in tutte le sue parti e spedirlo all’indirizzo sopra indicato. Si ringrazia per la gentile collaborazione data.  
We request your cooperation in filling this form,  in order to  keep out statistical data relevant to aircraft configuration up- to-date. The form should be filled in all 
its parts and sent to the above address. We thank you beforehand for the information given.  
MODULO APPLICAZIONE BOLLETTINO TECNICO 
TECHNICAL BULLETIN COMPLIANCE FORM 
Data: 
Date: 
Numero: 
Number: 
Revisione: 
Revision: 
Prego spedire a questo indirizzo: 
Please send to the following address: 
 
AGUSTAWESTLAND  S.p.A. 
CUSTOMER SUPPORT & SERVICES - ITALY
PRODUCT SUPPORT ENGINEERING DPT.
Via del Gregge, 100 
21015 Lonate Pozzolo (VA) - ITALY 
Tel.: +39 0331 664905 
Fax: +39 0331 664684
Telefono: 
Telephone: 
Fax: 
Data Applicazione B.T.: 
B.T. Compliance Date: 
Denominazione Cliente ed Indirizzo: 
Customer Name and Address: 
Modello Elicottero 
Helicopter Model S/N Matricola Tail Number Ore Totali Total Hours Ore D.U.R. T.S.O.

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