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ANC09LA100 · Grumman G-44A

17 Sept 2009 · Anchorage, AK, United States

Grumman G-44A · Accident: system/component malfunction/failure (non-power) during landing

From Merrill Field (MRI) to Merrill Field (MRI)

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Event

NTSB case
ANC09LA100
Event typeAccident: someone killed or seriously injured, or the aircraft substantially damaged (NTSB definition). Incident: an occurrence that affected or could have affected safety, short of that. Glossary
Accident
InvestigationHow far the investigation had got when the record was published: preliminary, ongoing, final or completed. Unknown where the source does not say. Glossary
Completed
API-reported fatalities
0 · all aircraft and ground
Ground fatalities
Unknown
OperationWhat kind of flying it was, grouped by the rules it flew under: airline (US Part 121), air taxi and commuter (Part 135), general aviation (Part 91 and similar), military or government. Glossary
General aviation
WeatherVisual meteorological conditions (VMC): good enough to fly by looking outside. Instrument conditions (IMC): cloud or low visibility, flying by instruments. Glossary
Visual Meteorological Cond

Grumman G-44A

Aircraft type
Grumman G-44
Category
Airplane
RegistrationThe aircraft's tail number, such as N12345 or G-ABCD. Registrations are reissued, so the same one years apart can be a different aircraft. Glossary
N86627
Operator
Richard R. Taylor · private individual
Onboard fatalities
Unknown
Route
From Merrill Field (MRI), Anchorage, AKTo Merrill Field (MRI), Anchorage, AK
Aircraft age
Not recorded
Flight rulesThe regulations the flight operated under: in the US, Part 91 (general aviation), Part 121 (airlines), Part 135 (air taxi and commuter) and others; for flights abroad, the NTSB's coarser commercial or non-commercial code. Glossary
Part 91: General Aviation
Phase of flightThe stage of the flight when things started to go wrong: standing, taxi, takeoff, initial climb, en route, maneuvering, approach or landing. Glossary
Landing · landing roll
Defining eventThe single coded event the NTSB judges best describes what happened (records from 2008 on). Older records name the first occurrence in the sequence instead. Glossary
System/component malfunction/failure (non-power)
DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
Substantial

Cause areas

  • Aircraft › Aircraft systems

Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.

NTSB narrative

The commercial pilot reported that he was landing his tailwheel-equipped amphibious airplane on a dry, paved runway at the conclusion of a local area postmaintenance flight operated under Title 14, Part 91 after a local facility had completed repairs to the right brake assembly. After landing, the pilot applied the brakes to slow the landing roll, and while depressing both brake pedals, the right brake pedal unexpectedly "went to the floor" and the airplane swerved to the left. The airplane ground looped to the left, sustaining substantial damage to the right wing and right aileron. A postaccident investigation revealed that a hydraulic supply line fitting on the airplane's right brake assembly had broken. The maintenance technician that did the repairs on the airplane's brake reported that the hydraulic supply line fitting was not removed during his work. He also said that he strongly suspected that the broken fitting might be an unapproved or "bogus" aircraft part due to an atypical thread pattern. An NTSB metallurgical examination revealed that the fractured fitting had failed due to a fatigue fracture. A Safety Board mechanical engineer noted that the broken fitting was marked with the "AN" (Air Force-Navy standards) identification stamp, signifying that it was approved for use in aircraft. Further investigation revealed that the fractured fitting was consistent in appearance to that of a fitting manufactured to meet the standards of a Joint Industrial Council (JIC), which is not intended for use in aircraft. The Safety Board mechanical engineer also noted that the two types of fitting are nearly indistinguishable except for the "AN" identification stamp. He added that without the aid of magnification, the "JIC" fittings and the "AN" fittings look identical. The "AN" fitting is reported to have a 40 percent increase in fatigue strength over the identical "JIC" fitting. There was no logbook entry which disclosed replacement of the hydraulic fittings, and the airplane's owner said that he was unaware when the brake line fittings had been replaced, but assumed it had been done prior to him purchasing the airplane. On July 22, 2008, the Federal Aviation Administration (FAA) issued an Advisory Circular (AC) 21-29C, change 1, which provides updated information and guidance to the aviation community for detecting suspected unapproved parts and reporting them to the FAA.

Probable cause

A fatigue fracture of an unapproved hydraulic brake line fitting, which resulted in a loss of control during the landing roll. Contributing to the accident was the installation of an unapproved part by an unknown maintenance personnel.

Verbatim NTSB analysis and probable cause from the NTSB dataset

Sources

NTSB record ANC09LA100
Event ID
20090918X15513
Case number
ANC09LA100
Dataset
full-current
Source SHA-256
5cf380f0061817c0331a6b2d8cc7e0ee3a79bea469a1001dc5c10e56f35f5ab3
Source notes (4)
  • Unreviewed is an editorial label, not an investigation status. API-sourced is not report-checked or human-reviewed. Explicit event totals are used without summing aircraft injury tables; onboard allocation is withheld. Unknown values remain unknown. The operation category is mapped from the NTSB-reported FAR part and has not been reviewed.
  • Filled from the NTSB case API where the bulk record had no value: investigation status. Values present in the bulk record are kept.
  • The date is the local date, which is the same as the UTC date the NTSB stores.
  • API snapshot SHA-256: 82eeb3f76f8a6f46e2ee93852e3b72b2c71126e477343377e5fbeb4d590548de; retrieved 2026-09-15T13:19:19.610Z.