AD 55-20-03
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Martin-Marietta Corporation | 202 | MARTIN Models 202, 202A, and 404 Aircraft |
| aircraft | Martin-Marietta Corporation | 202A | MARTIN Models 202, 202A, and 404 Aircraft |
| aircraft | Martin-Marietta Corporation | 404 | MARTIN Models 202, 202A, and 404 Aircraft |
Unsafe Condition
Nose gear steering shaft failures at the machined splines due to torsional fatigue.
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Required Actions
Inspect for cracks using dye penetrant, magnetic particle, or vapor blast inspections. Install new type shafts (Menasco P/N 526681) on all 202 and 202A aircraft and 404 aircraft with shimmy dampeners. Inspect original type shafts (Menasco P/N 511681) with added relief cut every 2,500 hours (or 1,000 hours for 404 without dampeners). Reinspect cracked original shafts at 325-hour intervals after grinding to remove cracks.
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Compliance Time
Compliance required as indicated.
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Affected Aircraft
Martin-Marietta Corporation Models 202, 202A, and 404 aircraft.
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Federal Register Abstract
Nose Gear Steering Shaft
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_55-20-03.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 55-20-03 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: MARTIN Models 202, 202A, and 404 Aircraft Subject: Nose Gear Steering Shaft Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: Make: Martin-Marietta Corporation Model: 202 | 202A | 404 Product Type: Aircraft Product Subtype: Large Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 55-20-03 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 55-20-03 SUBJECT HEADING: MARTIN Models 202, 202A, and 404 Aircraft ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 55-20-03 MARTIN: Applies to All Models 202, 202A, and 404 Aircraft. Compliance required as indicated. Several cases of nose gear steering shaft failures have occurred at the machined splines, due to torsional fatigue. Accordingly, the following inspections using dye penetrant, magnetic particle or vapor blast, are required to check for the presence of cracks. 1. New type shafts, Menasco P/N 526681, installed on all 202 and 202A aircraft, and on all 404 aircraft incorporating shimmy dampeners, must be inspected every 2,500 hours. On 404 aircraft not incorporating shimmy dampeners, the inspection must be conducted every 1,000 hours. Cracked shafts should be removed from service pending instructions from Martin. 2. Original type shafts, Menasco P/N 511681, which have never cracked, may be continued in service subject to the same conditions and inspections as the new type in item 1 providing the 1.628+0.005-inch relief cut is added. This is accomplished by grinding the serration run out circumferentially to a relief diameter of 1.628 inches starting 5/8 inch from upper shoulder, with 1/16- inch corner radii. Cracked shafts may be ground down to a minimum diameter of 1.530 inches to remove cracks. If cracks are removed, the shaft may be returned to service, but must be reinspected as required in the following paragraph 3. 3. All original type shafts which have been ground to remove cracks must be inspected at 325-hour intervals. Shafts may be ground down to a 1.530-inch minimum diameter to remove cracks. If cracks are removed, the shafts may be returned to service, continuing this inspection. If cracks are not removed at the 1.530 diameter, the shaft must be replaced. FOOTER:
Document Text
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AD Final Rules - DRS_55-20-03.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 55-20-03 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: MARTIN Models 202, 202A, and 404 Aircraft Subject: Nose Gear Steering Shaft Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: Make: Martin-Marietta Corporation Model: 202 | 202A | 404 Product Type: Aircraft Product Subtype: Large Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 55-20-03 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 55-20-03 SUBJECT HEADING: MARTIN Models 202, 202A, and 404 Aircraft ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 55-20-03 MARTIN: Applies to All Models 202, 202A, and 404 Aircraft. Compliance required as indicated. Several cases of nose gear steering shaft failures have occurred at the machined splines, due to torsional fatigue. Accordingly, the following inspections using dye penetrant, magnetic particle or vapor blast, are required to check for the presence of cracks. 1. New type shafts, Menasco P/N 526681, installed on all 202 and 202A aircraft, and on all 404 aircraft incorporating shimmy dampeners, must be inspected every 2,500 hours. On 404 aircraft not incorporating shimmy dampeners, the inspection must be conducted every 1,000 hours. Cracked shafts should be removed from service pending instructions from Martin. 2. Original type shafts, Menasco P/N 511681, which have never cracked, may be continued in service subject to the same conditions and inspections as the new type in item 1 providing the 1.628+0.005-inch relief cut is added. This is accomplished by grinding the serration run out circumferentially to a relief diameter of 1.628 inches starting 5/8 inch from upper shoulder, with 1/16- inch corner radii. Cracked shafts may be ground down to a minimum diameter of 1.530 inches to remove cracks. If cracks are removed, the shaft may be returned to service, but must be reinspected as required in the following paragraph 3. 3. All original type shafts which have been ground to remove cracks must be inspected at 325-hour intervals. Shafts may be ground down to a 1.530-inch minimum diameter to remove cracks. If cracks are removed, the shafts may be returned to service, continuing this inspection. If cracks are not removed at the 1.530 diameter, the shaft must be replaced. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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