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HOLDERS OF SERVICE LETTER GS--SL--36 FOR WHEEL INSPECTION AND OVERHAUL SCHEDULES USED ON ALL AIRCRAFT BRAKING SYSTEMS CORPORATION WHEEL ASSEMBLIES. Attached to this transmittal letter is Revision No. 7 of Service Letter GS--SL--36 (basic issue dated Jul 19/93). HIGHLIGHTS OF REVISION NO. 7 DATED 18 JANUARY 2006

REVISION NO. 7 CONTAINS ALL PAGES OF THE SERVICE LETTER. Pages which have been revised are outlined below, together with the Highlights of the revision.

EMAIL: [email protected]

TO:

1. All pages: A.

Added Revision 7 with new date.

2. Section II, page 3 of 8: A.

Added new paragraphs B.(6) thru B.(9) in reference to tires.

3. Section II, page 7 of 8: Deleted second paragraph in paragraph F.(2)(a).

Jan 18/06

GS--SL--36 Page 1 of 1

These commodities, technology or software were exported from the United States in accordance with the Export Administration Regulations. Diversion contrary to U.S. law is prohibited.

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TAME LINEA AEREA DEL EDUADOR

A.

EMAIL: [email protected] TAME LINEA AEREA DEL EDUADOR CO: 4414

These commodities, technology or software were exported from the United States in accordance with the Export Administration Regulations. Diversion contrary to U.S. law is prohibited.

SECTION I -- PLANNING INFORMATION A.

EFFECTIVITY: This General Service Letter is applicable to all Aircraft Braking Systems Corporation (ABSC) wheel assemblies used on various aircraft.

B.

REASON: The increment between overhauls varies greatly for each wheel assembly. Experienced operators who have a database of service history know the operation of their equipment and the inspection results. Where such experience is not available, it is necessary for operators to have guidelines to determine when normal overhaul procedures must be done on a wheel assembly.

C.

DESCRIPTION: This General Service Letter is issued to give operators guidelines for inspection and overhaul increments. The Overhaul and Component Maintenance Manuals are still the primary source for wheel inspection and overhaul information, however this service letter is a secondary source. It is not mandatory for operators to use the overhaul increments given in this Service Letter. Experienced operators can use their database of service history to better predict the overhaul increments and decide what procedures should be done at each overhaul. This Service Letter gives a guide for a start--up maintenance program.

EMAIL: [email protected]

SUBJECT: WHEEL INSPECTION AND OVERHAUL SCHEDULES

NOTE: Whenever the term ‘‘overhaul’’ is used in this General Service Letter, it is meant to encompass the full requirements of the Component Maintenance Manual with regards to Disassembly, Paint Removal, Inspection and Repair (Reference FAR 43.2). NOTICE

APPROVAL: This General Service Letter contains no modification information that revises the approved configuration and therefore does not require government or other regulatory agency approval.

E.

WEIGHT AND BALANCE: None.

F.

REFERENCE: (1)

All Aircraft Braking Systems Corporation Overhaul and Component Maintenance Manuals for all wheel assemblies.

(2)

Manufacturers Technical Data Specification 100, A.T.A. Specification 100

(3)

World Airlines Technical Operations Glossary (WATOG)

(4)

AP--763 Nondestructive Testing Manual with Procedures (basic issue date 18 March 1994). SECTION II -- ACCOMPLISHMENT INSTRUCTIONS

A.

GENERAL INFORMATION: (1) Aircraft Braking Systems Corporation (ABSC) aircraft wheel assemblies are manufactured to the highest quality standards. * ABSC is the registered trademark of Aircraft Braking Systems Corporation

Jul 19/93 GS--SL--36 Revision No. 7 (RELEASED: 1/18/06 ) Page 1 of 8 Jan 18/06 ALL RIGHTS These commodities, technology © or ABSC software2006 were exported from theRESERVED United States in accordance with the Export Administration Regulations. Diversion contrary to U.S. law is prohibited.

CO: 4414

D.

TAME LINEA AEREA DEL EDUADOR

AIRCRAFT BRAKING SYSTEMS CORPORATION (ABSC*) ASSUMES NO CONTRACTUAL, WARRANTY, PRODUCT LIABILITY OR OTHER OBLIGATION FOR ANY SUBSTITUTION OF OR ALTERATION TO ANY PART CONTAINED IN ANY ABSC WHEEL OR BRAKE ASSEMBLY INCLUDING ACCESSORIES NOT SPECIFICALLY AUTHORIZED BY ABSC OR FOR ANY ALTERATION NOT PERFORMED IN ACCORDANCE WITH ABSC APPROVED PROCEDURES.

ABSC wheel assemblies are designed to give a long and reliable service life when correctly maintained as told in the appropriate Component Maintenance Manual (CMM).

(b)

The CMMs give all the necessary inspection and repair procedures for normal maintenance of wheel assemblies. Some of the CMMs do not give a specific increment for when these procedures must be done. 1

Many airlines have asked for specific inspection/overhaul increments, but the Air Transportation Association (ATA), Specification 100, states: Time limits (including shelf life components) for scheduled inspections or checks in the procedures are specifically prohibited unless required by government regulation. Airlines do desire manufacturer’s recommendations, but if provided they must be in a separate document.

2

EMAIL: [email protected]

(a)

Each operator must schedule maintenance based on the condition of his equipment. Aircraft Braking System Corporation recommends on--condition maintenance be performed. NOTE: On--condition maintenance is defined as a primary maintenance process having repetitive inspections, checks or tests to determine the condition of units, systems or portions of structure with regard to continued serviceability (corrective action is taken when required by item condition).

3

(1)

ABSC recommends that on--condition maintenance be done (corrective action must be taken ‘‘at’’ the first signs of damage or replacement when damage exceeds manual limits).

(2)

There are many variables used to determine wheel retirements and to recommend the increments for wheel inspections and overhauls. These variables include: (a)

The amount of scatter in the frequency of wheel retirements between operators.

(b)

Repairs done to the wheel assembly and upgrades to the wheel assembly also change the length of the wheel service life.

(c)

The operation environment and the maintenance practices, which have a direct relationship with wheel service life, differ for each operator.

(3)

Operators who know more about the wheel’s service life history can create their own inspection and overhaul schedules.

(4)

For other operators, ABSC recommends the operators use the information given in this General Service Letter to make their wheel inspection and overhaul schedules.

(5)

ABSC recommends that operators use the comments given below when they make inspection and overhaul schedules for their wheel assemblies:

Jul 19/93 Revision No. 7 Jan 18/06

GS--SL--36 Page 2 of 8

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INSPECTION FREQUENCIES:

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B.

It is the purpose of this General Service Letter to give ABSC’s guidelines on inspection/overhaul increments to help operators who do not have a database of service history to establish their inspection/maintenance activities.

The guidelines given in this General Service Letter are intended to help operators make their own inspection and overhaul schedules. These guidelines must be changed to correspond to the actual service history of a particular wheel assembly. 1

If the wheels do not fail between overhauls, the inspection intervals can be increased.

2

If the wheels fail at tire change inspections, the inspection intervals must be decreased.

(c)

Aircraft wheels are highly stressed components that are sensitive to handling damage and maintenance procedures. Aircraft wheels have a finite life which can be maximized by careful handling. Operators must do only the maintenance procedures given in the CMM in order to maximize the service life of the wheel.

(d)

When wheel halves with different amounts of wear are used in the same wheel assembly, the inspection schedule for the most worn wheel half must be used.

(e)

If the service history of the wheel assembly (or one of the wheel halves) is not known, the wheel assembly must be overhauled at the next tire change.

(f)

Maintenance records must be kept for each wheel subassembly to make the maintenance schedules effective. This will make sure that the maintenance of the wheel halves is not lost. Include the information that follows in the maintenance record: repairs done to the wheel half, total accumulated mileage, the total number of landings and the number of tire changes.

(g)

Aircraft Braking Systems Corporation assumes no responsibility for wheel failures caused by poor/incorrect or infrequent overhaul procedures that result in property loss/ damage and/or personal injury.

(6)

If tires are replaced due to wear out, wheels and tie bolts should be inspected as told in Section II, paragraph F.

(7)

If tires are replaced due to tire failure (blow out, etc.), wheels and tie bolts should be inspected in accordance with the Component Maintenance Manual.

(8)

If tires are replaced for other reasons (cuts, flat spots, etc.), with less than 75 cycles, wheels and tie bolts should be inspected as follows:

(9)

(a)

Visually inspect wheels for damage, corrosion and missing paint. Repair wheel as necessary.

(b)

Visually inspect tie bolts for stretch, thread damage and corrosion. Replace tie bolts as necessary.

If tires have more than 75 cycles, inspect as told in Section II, paragraph F.

Jul 19/93 Revision No. 7 Jan 18/06

GS--SL--36 Page 3 of 8

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(b)

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It is recommended that operators with established inspection and overhaul schedules continue to use their inspection schedules.

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(a)

At each tire change examine the wheel assembly as follows: (a)

(b)

Make a visual inspection of the wheel assembly. 1

Write down the wheel assembly number, the wheel serial number and the number of landings.

2

Make a visual inspection of the wheel for physical damage at every tire change.

3

If the paint is discolored or the fusible plugs are melted, do a hardness inspection of the wheel assembly as told in the TESTING AND FAULT ISOLATION section of the applicable Component Maintenance Manual.

4

Make an inspection of the grease for contamination.

5

Make sure all of the wheel bolts and nuts are installed.

Clean the wheel assembly as told in the CLEANING section of the applicable Component Maintenance Manual. 1

Remove the tire from the wheel.

2

Carefully remove the bearing cones and seals from the wheel subassemblies. Clean the bearing cones and seals separately as told in the CLEANING section of the applicable Component Maintenance Manual.

3

Remove all components that have damage.

4

Vapor degrease the wheel tie bolts.

5

Clean all metal parts in dry--cleaning solvent, Specification ASTM D235 or MIL--PRF--680.

6

Dry all metal parts with low--pressure (15 psi or 1,03 bar), filtered air. NOTE: Make sure unwanted materials have been removed from all openings, holes that have threads and other areas.

7

Clean all rubber components in isopropyl alcohol.

(c)

Make an inspection of each component of the wheel assembly for damage. Pay special attention to the tapered roller bearings, the grease seals, the grease retainer baffles and the preformed packings.

(d)

Inspect or replace wheel tie bolts using one of the following procedures:

Jul 19/93 Revision No. 7 Jan 18/06

1

Ultrasonic Inspection

2

Magnaflux Inspection

3

Develop and use an appropriate replacement program for wheel tie bolts to make sure that tie bolts are replaced on a time limit established by satisfactory service performance or by the number of uses. GS--SL--36 Page 4 of 8

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(1)

EMAIL: [email protected]

WHEEL INSPECTION PROCEDURES:

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C.

Check nut locking feature in accordance with Component Maintenance Manual.

(f)

If the wheel has beam keys, refer to the applicable Component Maintenance Manual for beam key removal and inspection criteria and frequency.

(g)

Apply chemical film solution and paint to all damaged areas of the wheel assemblies.

(h)

2

Apply chemical film solution and paint to the components that were repaired and to all bare metal surfaces as told in the REPAIR section of the applicable Component Maintenance Manual.

Assemble the wheel assembly as told in the applicable Component Maintenance Manual. 1

Lubtork wheel tie bolts. Tighten the wheel tie bolts in a criss--cross pattern to the torque value given in the applicable Component Maintenance Manual.

2

Inflate the wheel for storage with Nitrogen gas.

ADDITIONAL INSPECTIONS: (1)

Do an eddy current inspection of the wheel assembly as told in the applicable Component Maintenance manual. (a)

Make an eddy current inspection of the bead seat area of the wheel halves for cracks as told in the CHECK section of the applicable Component Maintenance Manual.

WHEEL OVERHAUL PROCEDURES: (1)

At each wheel overhaul examine the wheel assembly as follows: (a)

(b)

Jul 19/93 Revision No. 7 Jan 18/06

Make a visual inspection of the wheel assembly. 1

Write down the wheel assembly number, the wheel serial number and the number of landings.

2

Make a visual inspection of the wheel for physical damage.

3

If the paint is discolored or the fusible plugs are melted, do a hardness inspection of the wheel assembly as told in the TESTING AND FAULT ISOLATION section of the applicable Component Maintenance Manual.

4

Make an inspection of the grease for contamination.

5

Make sure all of the wheel bolts and nuts are installed.

Disassemble the wheel assembly as told in the DISASSEMBLY section of the applicable Component Maintenance Manual. 1

Remove the tire from the wheel.

2

Remove the tie bolts, bearing cones, bearing seals, the grease retainer baffles, the drive keys, the fusible plugs, the pressure release plugs, the heat shields, the inflation valve subassembly and all other components from the wheel subassemblies.

GS--SL--36 Page 5 of 8

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E.

Repair or replace all damaged components as told in the REPAIR section of the applicable Component Maintenance Manual.

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D.

1

EMAIL: [email protected]

(e)

Clean the wheel assembly as told in the CLEANING section of the applicable Component Maintenance Manual. 1

Clean the bearing cones and seals separately as told in the CLEANING section of the applicable Component Maintenance Manual.

2

Vapor degrease the wheel tie bolts.

3

Clean all metal parts in dry--cleaning solvent, Specification ASTM D235 or MIL--PRF--680.

4

Dry all metal parts with low--pressure (15 psi or 1,03 bar), filtered air.

EMAIL: [email protected]

(c)

NOTE: Make sure unwanted materials have been removed from all openings, holes that have threads and other areas. Clean all rubber components in isopropyl alcohol.

6

Remove the paint from the wheel halves as told in the CLEANING section of the applicable Component Maintenance Manual. Use the appropriate chemical paint removal solvent or plastic media or equivalent.

1

Use fluorescent penetrant to make an inspection of the wheel halves for cracks.

2

Do an eddy current inspection of the bead seat areas of the wheel halves for cracks.

(e)

Make an inspection of the wheel halves, the wheel tie bolts, the bearing cones, the grease seals, the grease retainer baffles, the preformed packings and the O--ring seals for damage as told in the CHECK section of the applicable Component Maintenance Manual.

(f)

Repair all damage to the wheel halves and to the components as told in the REPAIR section of the applicable Component Maintenance Manual. Replace all components that cannot be repaired to the limits given.

(g)

Apply chemical film solution and paint to all damaged areas of the wheel assemblies. 1

(h)

Jul 19/93 Revision No. 7 Jan 18/06

Apply chemical film solution and paint to the components that were repaired and to all bare metal surfaces as told in the REPAIR section of the applicable Component Maintenance Manual.

Assemble the wheel assembly as told in the applicable Component Maintenance Manual. 1

Lubtork wheel tie bolts. Tighten the wheel tie bolts in a criss--cross pattern to the torque value given in the applicable Component Maintenance Manual.

2

Inflate the wheel for storage with Nitrogen gas. GS--SL--36 Page 6 of 8

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Do a non--destructive test (NDT) of the wheel halves as told in the CHECK section of the applicable Component Maintenance Manual.

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(d)

5

INSPECTION/OVERHAUL SCHEDULE -- FIXED WING AIRCRAFT: (1)

(2)

Commuter/Commercial Aircraft: (a)

At each tire change make an inspection of the wheel assembly as told in Section II, paragraphs C and D.

(b)

If a wheel overhaul has not been performed within the last five (5) tire changes or 1500 landings of the last overhaul, then perform a wheel overhaul at the next tire change. Refer to Section II, paragraph E. for wheel overhaul procedures.

Business and General Utility (GUA) Aircraft: (a)

G.

H.

EMAIL: [email protected]

F.

Recommended inspection and overhaul schedules for these aircraft are outlined in Table 1.

INSPECTION/OVERHAUL SCHEDULE -- ROTARY WING AIRCRAFT: (1)

Rotary wing aircraft include all types of helicopters.

(2)

Do a wheel overhaul at every second tire change. Refer to Section II, paragraph E. for wheel overhaul procedures.

(3)

At each tire change make an inspection of the wheel assembly as told in Section II, paragraphs C and D.

Not applicable. SECTION III -- MATERIAL INFORMATION Not applicable.

Jul 19/93 Revision No. 7 Jan 18/06

GS--SL--36 Page 7 of 8

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TAME LINEA AEREA DEL EDUADOR

A.

Inspection/Overhaul Schedule for Business and General Utility Aircraft TABLE 1

Jul 19/93 Revision No. 7 Jan 18/06

GS--SL--36 Page 8 of 8

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NOTE (1) CHECK CMM FOR EXCEPTION TO THIS TABLE

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Perform Inspections in Section II Paragraph “C” at Every Tire Change Additional Periodic Inspection Overhaul Section II, Paragraph “D” Section II, Paragraph “E” Perform Inspection at Perform Inspection at No. of Tire Change # or at the Next Tire Tire Change # or at the Next Tire Tire Landings Change after the Noted No. of Landings Change after the Noted No. of Landings Change 1 250 2 500 3 X 750 4 1000 5 1250 6 X 1500 7 1750 8 2000 9 X 2250 10 2500 11 2750 12 X 3000 13 3250 14 X 3500 15 3750 16 X 4000 17 4250 18 X 4500 19 X 4750 20 X 5000 21 X 5250 22 X 5500 23 X 5750 24 X 6000 25 X 6250 26 X 6500 27 X 6750 28 X 7000 29 X 7250 30 X 7500