# Agusta Bollettino Tecnico 109K-57: Revision A

- Rights: © Leonardo S.p.A. Filed by the FAA in regulations.gov docket FAA-2014-0472; AD 2014-23-02 incorporates this document by reference. Not covered by OpenAirDocs’ CC0 dedication.
- Document: [Agusta Bollettino Tecnico 109K-57](https://openairdocs.org/service-documents/leonardo/109k-57.md)
- Title as filed: U.S. DOT/FAA - Agusta BT No 109K-57 Rev A
- Pages: 7
- PDF: https://openairdocs.org/files/sha256/e5/a0/e5a0efb8b2812b8b02dc4bd729f8821dc7fdd2b476ad30afbc55a293d564bd81
- Page: https://openairdocs.org/service-documents/leonardo/109k-57/file/e5a0efb8b281

## Text

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

### Page 1

TRANSLATION OF 
BOLLETTINO TECNICO 
N°  109K-57 
 
The technical content of this document is approved 
under the authority of DOA nr EASA.21J.005. 
DATE   January  21, 2013 
 
 REV. A May  28, 2013
xx, 2011 
 
 
Compliance with 
This bollettino is:  
 
 
 
An appropriate entry should be made in the aircraft log book upon accomplishment. 
            If ownership of aircraft has changed, please forward to new owner. 
 
                           XX                              Page 1 of 6 
 
SUBJECT: INSPECTION OF GLEASON CROWN P/N 109-0403-07-103. 
 
REASON: Introduction of additional inspections of Gleason crown                                  
P/N 109-0403-07-103. 
 
HELICOPTERS AFFECTED: 
All the Agusta helicopters A109K2 that install the main transmission P/N 
109-0400-03-103 and have not applied the Bollettino Tecnico n° 109K-56. 
 
NOTE 3 
All the helicopter which have already 
performed the magnetic particle inspection 
required by the first edition of this BT are not 
required to repeat it up to the overhaul 
 
COMPLIANCE: 
Flight Hours (FH) accumulated 
by the tra nsmission:                     
P/N 109-0400-03-103,                       
on the effective date of this 
Bollettino 
Compliance time 
Less or equal to 2400 FH Before exceeding 200 FH 
after the 2400 FH 
accumulated by the 
transmission. 
More than 2400 and less than 
3000 FH 
Before exceeding the next 
200 FH accumulated by 
the transmission. 
A 
AgustaWestland S.p.A
Via Giovanni Agusta, 520
21017 Cascina Costa di Samarate (VA) Italy
Tel.: +39 0331 229111 - Fax: +39 0331 229605/222595
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.

### Page 2

B.T. 109K-57 
 
 
Page 2 of 6 
More or equal to 3000 FH and 
less than 3200 FH 
Perform the scheduled 
special inspection per the 
Maintenance Manual at 
3200 FH accumulated by 
the transmission. 
More than 3200 and less than 
4000 FH 
Before exceeding 200 FH 
after the 4000 FH 
accumulated by the 
transmission. 
More than 4000 FH and less than 
4600 FH 
Before exceeding the next 
200 FH accumulated by 
the transmission. 
More or equal to 4600 FH Before exceeding the 
overhaul limit (4800 FH) 
and then each 1600 FH 
after each TBO. 
 
 
 
DESCRIPTION: 
On Agusta A119 helicopter, during the execution of the main 
transmission P/N 109-0400-05-103 overhaul, a crack on Gleason crown 
P/N 109-0403-07-103 was found. 
The investigations show that the crack was originated from the bottom of 
one of 40 threaded holes and that the Gleason crown installed on the 
main transmission object of this Bollettino, could be subject to similar 
problem. 
 
This Bollettino therefore requires the introduction of two unscheduled 
inspection of the Gleason crown P/N 109-0403-07-103; One before the 
current scheduled 3200 FH, and one between the current scheduled 
3200 FH and 4800 FH inspections and the introduction of one repetitive 
inspection every 1600 flight hours, after the achievement of the each 
overhaul limit, scheduled at 4800 FH. In case of crack is found on 
Gleason crown P/N 109-0403-07-103, it is required to replace it with a 
new support assy Gleason crown P/N 109-0401-27-107 (welded to the 
mast support, therefore it does not have the 40 threaded holes) by mean 
application of BT 109K-56. 
 
REQUIRED MANPOWER: 
An estimated 24 manpower hours are required for compliance with this 
Bollettino. 
 
WARRANTY: 
Within the calendar terms mentioned at point “Compliance”, the parts 
required to apply the present Bollettino shall be supplied on a free of 
charge basis by AgustaWestland S.p.A. upon Customer’s request, with 
A

### Page 3

B.T. 109K-57 
 
 
Page 3 of 6 
 
the exception for Consumable materials and Tools; all the parts required 
after the “Compliance date” will be dispatched on charge basis for the 
Customer.  
 
Upon application of this Bollettino, Customers are requested to submit to 
AgustaWestland S.p.A. Warranty Administration the Bollettino Tecnico  
Compliance form attached to this Bollettino duly completed in all its parts, 
and relevant W.M.M. form ( (W)arranty Claim (M)aintenance Work Order 
(M)alfunction Report ).  
REQUIRED MATERIALS: 
 
N.A. 
SPECIAL TOOLS: 
N.A. 
WEIGHT AND BALANCE CHANGES:  
N.A. 
REFERENCES: 
A 109K2 Maintenance Manual; 
A119/A109 Series Overhaul Manual. 
 
PUBLICATIONS AFFECTED: 
A 109K2 Maintenance Planning Manual; 
A 109K2 Maintenance Manual. 
A119/A109 Series Overhaul Manual. 
COMPLIANCE INSTRUCTIONS: 
 
1. Prepare the helicopter on ground for a safe main tenance and 
disconnect any power supply in accordance with the instructions 
given in the A 109K2 Maintenance Manual. 
2. Gain access to Main transmission area removing t he 
Transmission Front Fairing and the Transmission Rea r fairing in 
accordance with the procedure given in the A 109K2 
Maintenance Manual. 
3. In accordance with the instructions given in the  A 109K2 
Maintenance Manual, remove the main rotor blades and the main 
rotor head. 
4. In accordance with the instructions given in the                        
A 109K2 Maintenance Manual remove the main transmis sion 
from the helicopter. 
5. Remove and perform the magnetic particle inspect ion of the 
Gleason crown as shown in A 109K2 Maintenance Manua l and 
Annex 1.

### Page 4

B.T. 109K-57 
 
 
Page 4 of 6 
 
 
NOTE 
During the execution of Gleason crown 
magnetic particle inspection, look at the 
presence of cracks at the bottom of threaded 
holes and in the areas adjacent to them. 
 
6. If after inspection cracks are found, apply BT n°  109K-56. 
7. If after the inspection no cracks are found, perform all the 
operations necessary to return the transmission in service as 
shown in the A 109K2 Maintenance Manual. 
 
8. In accordance with the instructions given in the A 109K2 Maintenance 
Manual, reinstall the Main rotor Head and n° 4 Main Rotor Blades. 
9. In accordance with the instructions given in the A 109K2 Maintenance 
Manual reinstall the Transmission Front Fairing and the Transmission 
Rear fairing. 
10. Return the helicopter to a ready-to-flight condition. 
11. Record compliance with this Bollettino in the helicopter log book.

### Page 5

B.T. 109K-57 
 
 
Page 5 of 6 
 
ANNEX 1  
 
MAGNETIC PARTICLE INSPECTION (ASTM-E-1444) 
 
A. General. 
(1) Consumable materials: 
 
WARNING: THE CONSUMABLE MATERIALS THE NOMENCLATURE OF WHICH IN THE LIST IS 
PREFIXED BY «D» ARE DANGEROUS MATERIALS. 
BEFORE USE, MAKE SURE TO KNOW THE SAFETY PRECAUTIONS AND FIRST AID 
INSTRUCTIONS PRINTED ON: 
— THE LABEL ON THE CONTAINER THE MATERIAL WAS SUPPLIED IN 
— THE MATERIAL SAFETY DATA SHEET 
— THE LOCAL SAFETY REGULATIONS. 
ALSO MAKE SURE THAT THE APPLICABLE FIRST AID MATERIALS ARE AVAILABLE. 
— (D) Paint remover. 
— (D) MEK  
— Abrasive pad . 
— (D) Aliphatic naphtha  
— Lubricating. 
(2) Other recommendations: 
 
NOTE: Refer to deals with the items in question for magnetic inspection data. 
B. Strip paint finish from the part with paint remover. Remove any remaining finish or aged 
sealant from the surfaces with a plastic scraper and MEK, or abrasive pad . 
C. Vapor degrease the part with aliphatic naphtha. Surfaces to be inspected must be free from 
oil, dirt, paint, corrosion, or other surface films, coatings, or conditions which could mask 
defects or give false indications. 
 
NOTE: All magnetic particle inspections must be conducted by the continuous process using the 
longitudinal and circular methods. The inspection process must be in accordance with the 
manufacturer's equipment instructions. 
D. Circular magnetization method. 
(1) Put the part to be inspected between the contact plates of the magnetizing unit so that 
electrical current passes through the part or through an electrical conductor that passes 
through the part. 
The electrical current used to produce the magnetic flux shall be 240 to 310 Ampere per 
cm of external diameter of the part. Proceed as follows: 
a. All contact areas must be clean and wet to prevent arcing or overheating of the part to be 
tested. 
b. The central electrical conductor must be as near the size of the openings as practicable. 
c. A central electrical conductor must be used when the length of a part is very small as 
compared to the diameter or when the wall thickness is very small compared to the 
diameter. 
d. Sharper defect indications are desired on the inner diameter of the part. 
e. Very small parts which are difficult to place between the heads or on a central conductor 
shall be inspected with the longitudinal method. 
E. Longitudinal magnetization method. 
(1) The part must be magnetized by placing the part in a coil and passing an electrical current 
through the coil. The number of ampere-turns used to magnetize the part must be 
determined by the formula:

### Page 6

B.T. 109K-57 
 
Page 6 of 6 
 
 
where: 
l = length of parts; 
d = diameter of the part; 
and the l/d ratio is between 9 and 3.
When the part has a l/d ratio greater than 9 use 5000 ampere
part several times to ensure complete coverage of the part.
A maximum of 15000 ampere
 
NOTE 1: Ampere-turn defines the amperage that passes through the coil multiplied by the number 
of turns in the coil. 
NOTE 2: The part should be placed off
long axis of the coil unless otherwise specified.
F. Application of magnetic particles in suspension 
(1) Prepare the solution; to do this, mix the magnetic particle powder to the suspension.
(2) Apply the magnetic particles in suspension; to do this, spray the liquid through a tube so 
as to obtain complete coverage of the surface under examination.
(3) Close the magnetization circuit 1/5 to 1/2 second while the part is covered with a film of 
liquid as necessary to give adequate indication.
(4) Discontinue spraying and leave parts to drip for 
NOTE: The part on which a film of liquid remains must be rinsed, magnetized and sprayed with 
the liquid per step (1). 
(5) After inspection, acceptable parts shall be cleaned and demagnetized. Check parts with a 
field indicator to ensure demagnetization.
(6) Apply a film of lubricating oil on the parts to prevent corrosion.
G. Inspect parts with black light. 
NOTE: Surface or subsurface defects will be revealed by magnetic particle accumulation around 
the defect. 
 
 
Recommended magnetization 
 
NOMENCL.  INSP. AREA  
 
AMP. 
Gleason 
crown  
Minor I.D.  
 
Major O.D.  
2000 
   
3400 
 
NOTE 
[1] Rotate part by 60°  and repeat the inspection at 6 points. 
and the l/d ratio is between 9 and 3. 
When the part has a l/d ratio greater than 9 use 5000 ampere-turns and magnetize the 
part several times to ensure complete coverage of the part. 
A maximum of 15000 ampere-turns shall be used on any part with a l/d ratio less than 3.
fines the amperage that passes through the coil multiplied by the number 
The part should be placed off-center of the coil with the long axis of the part parallel to the 
long axis of the coil unless otherwise specified. 
ication of magnetic particles in suspension - Continuous method. 
(1) Prepare the solution; to do this, mix the magnetic particle powder to the suspension.
(2) Apply the magnetic particles in suspension; to do this, spray the liquid through a tube so 
obtain complete coverage of the surface under examination. 
(3) Close the magnetization circuit 1/5 to 1/2 second while the part is covered with a film of 
liquid as necessary to give adequate indication. 
(4) Discontinue spraying and leave parts to drip for several seconds. 
The part on which a film of liquid remains must be rinsed, magnetized and sprayed with 
(5) After inspection, acceptable parts shall be cleaned and demagnetized. Check parts with a 
magnetization. 
(6) Apply a film of lubricating oil on the parts to prevent corrosion. 
 
Surface or subsurface defects will be revealed by magnetic particle accumulation around 
ecommended magnetization currents for magnetic particle inspection
CIRCULAR MAGNETISM 
 
AMP.  
CENTR COND 
DIA 
(mm)  
INSP. 
AXIS  NOTE  
2000  
3400  
50  
 
Thread-ing bar 
(INSU- LATED)  
Longit.  [1]  
] Rotate part by 60°  and repeat the inspection at 6 points.  
 
 
turns and magnetize the 
turns shall be used on any part with a l/d ratio less than 3. 
fines the amperage that passes through the coil multiplied by the number 
center of the coil with the long axis of the part parallel to the 
(1) Prepare the solution; to do this, mix the magnetic particle powder to the suspension. 
(2) Apply the magnetic particles in suspension; to do this, spray the liquid through a tube so 
(3) Close the magnetization circuit 1/5 to 1/2 second while the part is covered with a film of 
The part on which a film of liquid remains must be rinsed, magnetized and sprayed with 
(5) After inspection, acceptable parts shall be cleaned and demagnetized. Check parts with a 
Surface or subsurface defects will be revealed by magnetic particle accumulation around 
currents for magnetic particle inspection. 
LONGITUDINAL 
MAGNETISM  
INSP. 
AREA  
AMP.  
x 
TURNS  
NOTE  
Entire  
item  15000  [4]

### Page 7

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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