# AAI Alert Service Bulletin AA-07109: No revision named

- Rights: © AAI. Filed by the FAA in regulations.gov docket FAA-2012-0083, the docket of AD 2012-11-13. Not covered by OpenAirDocs’ CC0 dedication.
- Document: [AAI Alert Service Bulletin AA-07109](https://openairdocs.org/service-documents/aai/aa07109.md)
- Title as filed: U.S. DOT/FAA - Aeronautical Accessories, Inc., Service Information
- Pages: 15
- PDF: https://openairdocs.org/files/sha256/1d/43/1d431139ec7ac1afe92e9968466b34bbce4e5c5851c6529aaa7d985708f6e258
- Page: https://openairdocs.org/service-documents/aai/aa07109/file/1d431139ec7a

## Text

Some pages are OCR from a scan. OCR can misread letters and numbers. Each page's text from the PDF; open the PDF at a page with #page=N.

### Page 1

P.O. BOX 3689 BRISTOL, TENNESSEE 37625-3689 USA 
TELEPHONE: 423-538-5151             TOLL FREE: 800-251-7094 
TELEFAX: 423-538-8469          E-MAIL: sales@aero-access.com 
techsupport@aero-access.com 
ALERT SERVICE BULLETIN 
ASB No. AA-07109 
No Revision  
SUBJECT: High Landing Gear Aft Crosstubes 
 P/N 412-321-104 / 412-321-304  
MODELS AFFECTED: Bell Helicopter Textron model 412, 412EP and 412CF and 
Agusta S.p.A. model AB412, AB412EP helicopters with 
Aeronautical Accessories, Inc. P/N 412-321-104 / 
412-321-304 High Aft Crosstubes installed in accordance 
with STC SR01052AT. 
COMPLIANCE: Part A: Within the next 50 flight hours, but not later than 
June 30, 2008, establish a high aft crosstube takeoff/landing 
life limit of 20,000 on P/N 412-321-304.  
 High aft crosstubes for which flight hours are unknown, or 
the number of takeoff/landings cannot be determined, must 
be replaced within the next 450 takeoff/landings. 
 High aft crosstubes with historical information establishing a 
number of takeoffs/landings greater than 20,000 must be 
replaced within the next 450 takeoff/landings. 
 Part B: Prior to 2500 takeoff/landings.  
 High aft crosstubes with historical information establishing a 
number of takeoffs/landings greater than 2500 must accomplish 
Part B within 50 flight hours or 250 takeoff/landings, whichever 
comes first, of the receipt of this bulletin. 
 Part C: Within 450 takeoff/landings after accomplishment of 
Part B, and every 450 takeoff/landings thereafter. 
IF OWNERSHIP OF AIRCRAFT HAS CHANGED, PLEASE FORWARD THIS BULLETIN TO NEW OWNER

### Page 2

412, 412EP, 412CF ALERT SERVICE BULLETIN ASB No. AA-07109 
AB412, AB412EP HIGH AFT CROSSTUBE  No Revision 
 Part D: Prior to 2500 takeoff/landings and every 12 months or 
2500 takeoff/landings, whichever comes first, thereafter. 
 High aft crosstubes with historical information establishing a 
number of takeoffs/landings greater than 2500 must 
accomplish Part D within 1 month of the receipt of this bulletin. 
 Part E: Prior to 7500 takeoff/landings and every 5000 
takeoff/landings thereafter. 
 High aft crosstubes with historical information establishing a 
number of takeoffs/landings greater than 7500 must 
accomplish Part E within 3 months of the receipt of this 
bulletin. 
 Part F:  Within the next 25 flight hours, but not later than May 
15, 2008. 
DESCRIPTION: Aeronautical Accessories, Inc. has conducted a review of 
the high aft crosstube in response to three reported field 
failures.  Our analysis indicates a takeoff/landing life must 
be assigned to P/N 412-321-304 high aft crosstube and 
additional scheduled inspections must be conducted on 
both P/N 412-321-104 and 412-321-304 high aft crosstubes. 
 Part A of this bulletin establishes a 20000 takeoff/landing 
life on P/N 412-321-304 high aft crosstube.  P/N 
412-321-104 high aft crosstube is already subject to the 
retirement life.  This bulletin provides the information 
necessary to calculate the number of takeoffs/landings.  If 
the total number of takeoff/landings is less than the 
recommended life, record all takeoff/landings until 
component life is achieved or component is otherwise 
removed from service. 
 Part B of this bulletin provides instructions to clean and 
inspect two areas on the bottom of the high aft crosstube.  
Means to protect this area with primer and a clear coat are 
also included.  P/N 412-321-104, serial number AA-1274 
and subsequent, crosstubes are manufactured with the two 
inspection areas primed and clear-coated. 
 Part C of this bulletin provides instructions to conduct a 
recurring visual inspection of the two primed and clear 
coated areas of the high aft crosstube after the 
accomplishment of Part B.

### Page 3

412, 412EP, 412CF ALERT SERVICE BULLETIN ASB No. AA-07109 
AB412, AB412EP HIGH AFT CROSSTUBE  No Revision 
 Part D of this bulletin provides instructions to conduct a 
recurring dimensional inspection of the skid gear to identify 
permanent deformation of the crosstube. 
 Part E of this bulletin provides instructions to conduct a 
recurring fluorescent penetrant inspection of the high aft 
crosstube. 
 Part F of this bulletin provides clarification on helicopter 
towing instructions to prevent crosstube damage or failure 
as a result of ground handling or towing. 
APPROVAL: The engineering aspects of this bulletin are FAA/DER 
approved. 
MANPOWER: PART A: Approximately 0.5 hours. 
 PART B: Approximately 3.0 hours. 
 PART  C: Approximately 0.5 hours 
 PART D: Approximately 1.0 hours. 
 PART E: Approximately 24.0 hours.   
 Manhours are based on hands-on time and may vary with 
personnel or facilities available.

### Page 4

412, 412EP, 412CF ALERT SERVICE BULLETIN ASB No. AA-07109 
AB412, AB412EP HIGH AFT CROSSTUBE  No Revision 
AERONAUTICAL ACCESSORIES, INC. 
April 3, 2008  Page 4 of 15 
MATERIAL: 
The following Customer supplied materials are required to comply with this 
bulletin: 
TABLE 1 – PARTS LIST 
CUSTOMER SUPPLIED CONSUMABLE MATERIALS 
Qty Description  
AR MIL-R-81294, Type I or II Chemical Paint Remover 
AR MIL-PRF-85582 Primer  (PRC-DeSoto EWDE 072A/B) 
AR MIL-PRF-85285, Type I Gloss Clear Coat Paint  (Deft 03X085) 
AR MIL-PRF-87937 Cleaning Compound, Aerospace Equipment 
  
NOTE 
The MIL-PRF-85582 primer (PRC-DeSoto EWDE 072A/B)  
[packaged as a 1-gallon, 1-qt (Parts A&B) kit (P/N 
EWDE072)] and the MIL-PRF-85285, Type I clear coat paint 
(Deft 03X085) [packaged as a 3-qt kit  (P/N MIL-PRF-85285)] 
may be procured from a Bell Heli copter Supply Center.  The 
primer and paint may also be procured [packaged in 1-qt, 
primer and paint, kits (P/N 1272K)] from Aerospace 
Products, Inc., 6413 Midway R oad, Halton City, TX 76117 
(817-332-1669). 
SPECIAL TOOLS REQUIRED:  10X magnifying glass 
WEIGHT AND BALANCE:  Not affected 
PUBLICATIONS AFFECTED: 
Installation Instructions, report number AA-95005 
Instructions for Continued Airworthiness, report number AA-01136  
ADDITIONAL INFORMATION: 
Any questions regarding this bulletin should be addressed to: 
AERONAUTICAL ACCESSORIES, INC. 
P.O. Box 3689 
Bristol, 37625-3689 TN 
PRODUCT SUPPORT 
1-800-251-7094 
techsupport@aero-access.com

### Page 5

412, 412EP, 412CF ALERT SERVICE BULLETIN ASB No. AA-07109 
AB412, AB412EP HIGH AFT CROSSTUBE  No Revision 
AERONAUTICAL ACCESSORIES, INC. 
April 3, 2008  Page 5 of 15 
ACCOMPLISHMENT INSTRUCTIONS 
Upon receipt of this bulletin, determine by part number if affected high aft crosstube is 
installed.  If affected crosstube is installed, perform the actions contained in this bulletin.  
Any crosstube failing inspection shall be removed from service and replaced with an 
airworthy crosstube. 
PART A  INSPECTION REQUIREMENTS AND HISTORICAL RECORDS  
1. Verify all high aft crosstubes, P/N 412-321-104 and 412-321-304, comply with 
the inspection criteria of the Instructions for Continued Airworthiness report 
number AA-01136 and BHT-412-MM-2 (Bell Helicopter model 412 Maintenance 
Manual). 
A retirement life has been established for the following high skid gear aft 
crosstubes.  A Historical Record is provided (Figure 4) for recording of 
takeoff/landing operations for the listed life-limited crosstubes. 
PART NUMBER (1) COMPONENT LIFE LIMIT 
(EVENTS) (2) 
412-321-104 Aft Crosstube, High Skid Gear 20,000 
Takeoff/Landings 
412-321-304 Aft Crosstube, High Skid Gear 20, 000 
Takeoff/Landings 
NOTES: 
(1) The airworthiness limitation for part number listed applies to all successive dash numbers 
for that component unless otherwise specified. 
(2) Either landings or takeoff may be counted. 
 
These Airworthiness Limitations are FAA approved and specify maintenance 
required under §§ 43.16 and 91.403 of the Federal Aviation Regulations unless 
an alternative program has been FAA approved. 
2. Create a Historical Record form to  track P/N 412-321-304 high aft crosstube 
takeoff/landing life per the compliance section of this bulletin. Those operators 
that have recorded the number of takeoff/landings are subject to the 20,000 
takeoff/landing limit. 
NOTE 
Helicopters with takeoff/landings  that are higher than the 
average of 10 per hour must substitute the higher value in all 
estimated calculations. 
3. If the actual takeoff/landing information is not available it is permissible to 
estimate the number. To determine the number of takeoff/landings on the 
crosstube, multiply the airframe hours by a factor of ten. 
4. Place the calculated takeoff/landing in formation on the Historical Record form 
and track the applicable life as per the compliance section of the bulletin. 
5. Replace life limited crosst ubes per the Instructions for Continued Airworthiness, 
report number AA-01136.

### Page 6

412, 412EP, 412CF ALERT SERVICE BULLETIN ASB No. AA-07109 
AB412, AB412EP HIGH AFT CROSSTUBE  No Revision 
AERONAUTICAL ACCESSORIES, INC. 
April 3, 2008  Page 6 of 15 
NOTE 
Aeronautical Accessories Inc. has discontinued sale of P/N 
412-321-304 high aft crosstube Assembly.  P/N 412-321-104 
high aft crosstube is completely interchangeable with P/N 
412-321-304. 
PART B INITIAL INSPECTION REQUIREMENT FOR P/N 412-321-104 AND  
P/N 412-321-304 CROSSTUBES 
NOTE 
Crosstube visual inspection is conducted with aircraft at rest 
on skid landing gear; minimum gr oss weight at inspection is 
9,000 pounds. 
CAUTION 
Chemical removers shall be used only in areas of 
adequate ventilation.  Suitable goggles or face masks, 
chemical resistant gloves, boots and clothing shall be 
worn to avoid contact of ch emical removers with eyes, 
skin and clothing.  Chemical removers shall further be 
handled in accordance with applicable OSHA 
regulations, state and local safety codes, and company 
established safety standards and policies. 
NOTE 
P/N 412-321-104 Crosstubes wit h serial number AA-1274 
and subsequent are manufactured with the two inspection 
areas primed and clear-coated. St eps 1 through 3 of Part B 
may be skipped unless opaque pai nt has been applied to 
either inspection area described below and in Figure 1. 
1. Prepare crosstube inspection areas by c hemically removing crosstube paint and 
primer from an area 2.0 ±0.25 inches wide extending between BL 18 and BL 30 
at the center-bottom surface of the crosstube on both the left and the right sides 
of the crosstube (see Figure 1).   
2. Apply MIL-R-81294, Type I or  II chemical paint remover with a brush and allow it 
to set from 15 to 45 minutes to soften paint.   
3. Using a stiff fiber brush and clean water, rinse paint from crosstube.  If required, 
use abrasive pad (Scotch-Brite, Type A) and MIL-R-81294, Type I or II chemical 
paint remover to aid in lifting paint.  Brush crosstube with abrasive pad in the 
longitudinal direction, using care so as not to abrade crosstube metal surface.   
4. Rinse part clean with clean water and dry thoroughly.  Reapplication of chemical 
paint remover may be required to ensure that paint and primer is completely 
removed so that the metal surface of the cross tube is clearly visible.  
5. Using at least 10X magnification and a strong light source, visually inspect the 
stripped areas for indications of cracking.  If cracking is suspected, fluorescent 
penetrant inspect crosstube per ASTM E1417, Type I, Method B, C, or D, Level 2 
in accordance with Bell Helicopter Standard Practices Manual (BHT-ALL-SPM).

### Page 7

412, 412EP, 412CF ALERT SERVICE BULLETIN ASB No. AA-07109 
AB412, AB412EP HIGH AFT CROSSTUBE  No Revision 
AERONAUTICAL ACCESSORIES, INC. 
April 3, 2008  Page 7 of 15 
WARNING 
IF CRACKING IS DISCOVERED, THE CROSSTUBE IS NO 
LONGER AIRWORTHY AND MUST BE IMMEDIATELY 
REPLACED. REPLACE CROSSTUBE PER APPLICABLE 
INSTRUCTIONS IN INSTRUCTIONS FOR CONTINUED 
AIRWORTHINESS, REPORT NUMBER AA-01136.  
6. Following crosstube inspection, coat the stripped crosstube area with 
MIL-PRF-85582 primer (.0006 – .0009 thick) by spraying in accordance with 
manufacturer’s instructions.  Allow primer to cure per manufacturer instructions.  
NOTE 
The MIL-PRF-85582 primer (PRC-DeSoto EWDE 072A/B)  
[packaged as a 1-gallon, 1-qt (Parts A&B) kit (P/N 
EWDE072)] and the MIL-PRF-85285, Type I clear coat paint 
(Deft 03X085) [packaged as a 3-qt kit  (P/N MIL-PRF-85285)] 
may be procured from a Bell Heli copter Supply Center.  The 
primer and paint may also be procured [packaged in 1-qt, 
primer and paint, kits (P/N 1272K)] from Aerospace 
Products, Inc., 6413 Midway R oad, Halton City, TX 76117 
(817-332-1669). 
7. Following primer cure, paint the area with polyurethane clear coat paint per 
MIL-PRF-85285 by spraying in accordance with manufacturer’s instructions.  
Allow paint to cure per manufacturer instructions.  
8. Annotate aircraft records that Part B of this bulletin has been accomplished. 
9. Return aircraft to service. 
PART C SCHEDULED VISUAL IN SPECTION REQUIREMENTS FOR  
P/N 412-321-104 AND P/N 412-321-304 
NOTE 
The following crosstube inspection is to be incorporated into 
the inspection intervals/methods identified in Instructions for 
Continued Airworthiness, report number AA-01136.   
NOTE 
Crosstube visual inspection is conducted with aircraft at rest 
on skid landing gear; minimum gr oss weight at inspection is 
9,000 pounds. 
1. Use MIL-PRF-87937 cl eaning compound prepared in accordance with the 
manufacturer’s recommendations to clean all residue and dirt from the cross tube 
surfaces shown in Figure 1. 
2. Using at least 10X magnification and a strong light source, visually inspect the 
clear coated areas for indications of cracking.

### Page 8

412, 412EP, 412CF ALERT SERVICE BULLETIN ASB No. AA-07109 
AB412, AB412EP HIGH AFT CROSSTUBE  No Revision 
AERONAUTICAL ACCESSORIES, INC. 
April 3, 2008  Page 8 of 15 
3. If cracking is suspected, remove clear  coat and primer per steps 2 thru 4 of Part 
B, and fluorescent penetrant inspect crosstube per ASTM E1417, Type I, Method 
B, C, or D, Class 2, in accordance with Bell Helicopter Standard Practices 
Manual (BHT-ALL-SPM).  If cracking is not confirmed, reapply clear coat and 
primer per steps 6 and 7 of Part B.  If cracking is confirmed, remove crosstube 
from service. 
WARNING 
IF CRACKING IS DISCOVERED, THE CROSSTUBE IS NO 
LONGER AIRWORTHY AND MUST BE IMMEDIATELY 
REPLACED.  REPLACE CROSSTUBE PER APPLICABLE 
INSTRUCTIONS IN INSTRUCTIONS FOR CONTINUED 
AIRWORTHINESS, REPORT NUMBER AA-01136   
4. Annotate aircraft records to indicate  that Part C of this bulletin has been 
accomplished; and return aircraft to service. 
PART D SCHEDULED LANDING GEAR DEFLECTION INSPECTION 
REQUIREMENTS FOR P/N 412-321-104 AND P/N 412-321-304 
NOTE 
The following crosstube inspection is to be incorporated into 
the inspection intervals/methods identified in Instructions for 
Continued Airworthiness, report number AA-01136.   
1. Hoist or jack the helicopter until no weight is on the skid gear. 
2. Measure the lateral distance bet ween the two forward Crosstube cap 
assemblies. Measure the lateral distance between the two aft Crosstube cap 
assemblies. Divide these dimensions by two to determine the helicopter 
centerline, BL 0.00. 
3. Measure the Crosstube horiz ontal deflection from the centerline of the helicopter, 
BL 0.00, to the outside of the skid tubes. 
4. The Crosstube horizontal deflection as measured in step 3 above must be within 
the limits as shown in Figure 2.  Crosstubes that measure outside of the limits 
must be replaced. 
5. Inspect landing gear assembly in acco rdance with Instructions for Continued 
Airworthiness report number AA-01136 and BHT-412-MM damage limits.  
6. Repair or replace components that ar e damaged in excess of repairable limits. 
7. Annotate aircraft records to indicate  that Part D of this bulletin has been 
accomplished; and return aircraft to service.

### Page 9

412, 412EP, 412CF ALERT SERVICE BULLETIN ASB No. AA-07109 
AB412, AB412EP HIGH AFT CROSSTUBE  No Revision 
AERONAUTICAL ACCESSORIES, INC. 
April 3, 2008  Page 9 of 15 
PART E COMPONENT OVERHAUL REQU IREMENTS FOR P/N 412-321-104 
AND P/N 412-321-304 
The Component Overhaul Schedule, Table 2, summarizes the overhaul interval for 
high aft crosstube components.  
NOTE 
Neither the assignment of a time period overhaul of a 
component nor failure to assign a time period for overhaul of 
a component constitutes a warra nty of any kind.  The only 
warranty applicable to the co mponent is that warranty 
included in the Purchase Agreement for the component. 
Time between overhauls and inspection periods is based upon experience, testing, 
and engineering judgment and is subject to change at the sole discretion of 
Aeronautical Accessories Inc. or an appropriate government agency. 
WARNING 
ALL PARTS REMOVED, DUE TO REACHING THEIR 
LIMITS OR AS A RESULT OF AN ACCIDENT/INCIDENT 
AND DEEMED UNAIRW ORTHY, SHALL BE 
PERMANENTLY MARKED AS SCRAP OR PHYSICALLY 
DESTROYED TO THE EXTENT THAT THERE IS NO 
CHANCE OF REPAIR OR INSTALLATION ON ANY 
HELICOPTER OR COMPONENT. 
TABLE 2 – COMPONENT OVERHAUL SCHEDULE 
PART NUMBER NOMENCLATURE OVERHAUL INTERVAL 
412-321-104 Aft Crosstube, High 
Skid Gear 
Prior to 7500 Takeoff/Landings and 
every 5000 Takeoff/Landings thereafter 
412-321-304 Aft Crosstube, High 
Skid Gear 
Prior to 7500 Takeoff/Landings and 
every 5000 Takeoff/Landings thereafter 
   
E.1 Disassembly Instructions 
1. Remove Aft Crosstube Assembly in acco rdance with Instructions for Continued 
Airworthiness report number AA-01136. 
2. Remove Aft Crosstube Beam Assembly in accordance with Instructions for 
Continued Airworthiness report number AA-01136. 
NOTE 
The Upper Center Support on the Aft Crosstube is bonded 
with structural adhesive and is not designed for removal. 
3. Remove both Aft Crosstube Clamp Asse mblies in accordance with Instructions 
for Continued Airworthiness report number AA-01136.

### Page 10

412, 412EP, 412CF ALERT SERVICE BULLETIN ASB No. AA-07109 
AB412, AB412EP HIGH AFT CROSSTUBE  No Revision 
AERONAUTICAL ACCESSORIES, INC. 
April 3, 2008  Page 10 of 15 
E.2 Cleaning and Preparation 
1. Remove aged sealant by scraping with a shar p piece of plastic.  Finish by lightly 
sanding with 400 grit abrasive cloth or paper in the longitudinal direction of the 
crosstube. 
WARNING 
DO NOT SAND CROSSTUBE IN A CIRCUMFERENTIAL 
DIRECTION. 
2. Prepare crosstube by chemically re moving crosstube paint and primer outboard 
of the Upper Center Support to top of saddles.  See Figure 3. 
CAUTION  
Protect Upper Center Support area to prevent 
contamination by paint strippers and penetrant 
inspection chemicals. 
a. Apply MIL-R-81294, Type I or II chem ical paint remover with a brush and 
allow it to set from 15 to 45 minutes to soften paint.   
b. Using a stiff fiber brush and clean wa ter, rinse paint from crosstube.  If 
required, use abrasive pad (Scotch-Brite, Type A) and MIL-R-81294, Type I 
or II chemical paint remover to aid in lifting paint.  Brush crosstube with 
abrasive pad in the longitudinal direction, using care so as not to abrade 
crosstube metal surface.   
c. Rinse part clean with clean water and dry thoroughly.  Reapplication of 
chemical paint remover may be required to ensure that paint and primer is 
completely removed so that the (bare) metal surface of the cross tube is 
clearly visible. 
3. When parts are not to be processed immediately after cleaning, apply corrosion 
preventive oil, to all parts to protect against corrosion. Wrap parts in barrier 
material and secure with tape. 
E.3 Inspection 
1. Inspect crosstube outboard of Upper Center Support area using fluorescent 
penetrant method per ASTM E1417, Type I, Method B, C, or D, Level 2, in 
accordance with Bell Helicopter Standard Practices Manual (BHT-ALL-SPM).  
Refer to BHT-ALL-SPM for fluorescent penetrant inspection procedures. 
2. Damage limits are specified in Instruct ions for Continued Airworthiness, report 
number AA-01136 and BHT-412-MM-2 (Bell Helicopter model 412 Maintenance 
Manual). 
E.4 Repair 
1. Repair damage within repai rable limits in accordance with Instructions for 
Continued Airworthiness report number AA-01136.

### Page 11

412, 412EP, 412CF ALERT SERVICE BULLETIN ASB No. AA-07109 
AB412, AB412EP HIGH AFT CROSSTUBE  No Revision 
AERONAUTICAL ACCESSORIES, INC. 
April 3, 2008  Page 11 of 15 
2. Refinish crosstube by applying MIL- PRF-85582 primer and MIL-PRF-85285 paint 
(or equivalent) per manufacturer instructions to the stripped areas.  The areas to 
be inspected per Part B should be masked to omit MIL-PRF-85285 paint as 
shown in Figure 1. Paint inspection areas with MIL-PRF-85285 Type I Gloss 
Clear coat as described in Part B of this bulletin. 
E.5 Assembly Instructions 
1. Assemble both Aft Crosstube Clamp Asse mblies in accordance with Instructions 
for Continued Airworthiness report number AA-01136. 
2. Assemble Aft Crosstube Beam Assembly in accordance with Instructions for 
Continued Airworthiness report number AA-01136. 
3. Install Aft Crosstube Assembly to airc raft in accordance with Instructions for 
Continued Airworthiness report number AA-01136. 
4. Annotate aircraft records to indicate that Part E of this bulletin has been 
accomplished; and return aircraft to service. 
PART F  TOWING AIRCRAFT 
Helicopter towing operations must be conducted in accordance with BHT-412-MM-2 
(Bell Helicopter model 412 Maintenance Manual) and 412-OSN-07-32 (Landing 
Gear Maintenance and Handling).  Manufacturer towing requirements are applicable 
to any aircraft being towed with weight on gear.  This includes towing aircraft with 
ground handling wheels installed and aircraft resting on moveable platforms. 
CAUTION 
Failure to follow manufacturer  towing instructions may 
result in crosstube damage and/or failure.

### Page 12 (OCR)

412, 412EP, 412CF  ALERT SERVICE BULLETIN  ASB No. AA-07109
AB412, AB412EP  HIGH AFT CROSSTUBE  No Revision
• ZONE B
HIGH AFT
CROSSTUBE
B.L.  B.L.  B.L
30.0  18.0  0.0
REMOVE PAINT/PRIMER FROM
HATCHED AREA AND CLEAR COAT
ARC LENGTH  45'
2.00
INSPECTION AREA
LEFT AND RIGHT SIDES  • TOP
AFT CROSSTUBE
B.L.  B.L.  45°
30.0  18.0
VIEW A-A  VIEW B-B
VIEW LOOKING UP AT
BOTTOM OF CROSSTUBE
TYPICAL
BOTH SIDES
FIGURE 1 - CLEAR COAT AND INSPECTION AREA
AERONAUTICAL ACCESSORIES, INC.
April 3, 2008  Page 12 of 15

### Page 13

412, 412EP, 412CF ALERT SERVICE BULLETIN ASB No. AA-07109 
AB412, AB412EP HIGH AFT CROSSTUBE  No Revision 
AERONAUTICAL ACCESSORIES, INC. 
April 3, 2008  Page 13 of 15 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
                  
 
 
 
“A” “B” Part Number Model Effectivity in. mm in. mm 
412-321-104 / 412-321-304 412 Aft Crosstube (High) 57.00 1448 59.00 1499 
 
FIGURE 2 – HIGH LANDING GEAR DEFLECTION LIMITS

### Page 14

412, 412EP, 412CF ALERT SERVICE BULLETIN ASB No. AA-07109 
AB412, AB412EP HIGH AFT CROSSTUBE  No Revision 
AERONAUTICAL ACCESSORIES, INC. 
April 3, 2008  Page 14 of 15 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
FIGURE 3 – PAINT REMOVAL AREA

### Page 15 (OCR)

412, 412EP, 412CF  ALERT SERVICE BULLETIN  ASB No. AA-07109
AB412, AB412EP  HIGH AFT CROSSTUBE  No Revision
REASON  FOR  REMOVAL
REMOVAL DATA  COMPONENT  CYCLES SINCE  NEW  REMAINING TO
REMOVED AT  A/C HOURS  ACCUMULATED  TAKE-OFF / LANDINGS
HISTORICAL SERVICE RECORD  AFT CROSSTUBE ASSEMBLY  SERVICE LIFE (TAKE-OFF/LANDINGS)  COMPONENT  DATE  CYCLES SINCE  NEW  TIME/DATE
INSTALLATION DATA  INSTALLED ON BY (ACTIVITY)  INSTALLED AT  A/C HOURS  REMAINING TO  ACCUMULATED  RETIREMENT  TAKE-OFF / LANDINGS
Component Name:  Part Number:  Serial Number:  DATE  A/C NUMBER  TIME/DATE
FIGURE 4 - HISTORICAL SERVICE RECORD
AERONAUTICAL ACCESSORIES, INC.
April 3, 2008  Page 15 of 15

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