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Atlas / NTSB / WPR21LA323

NTSB CAROL · Event

Event WPR21LA323

2021-08-15 Albuquerque, New Mexico, United States Airport · ABQ None 1 aircraft Status: Completed

Registry · N8029G

FAA Aircraft Registry record.

Make / Model

CESSNA 177RG

Year of manufacture

1970 · 51 years old at event

Engine

LYCOMING IO-360-A1B6D (200 hp)

Seats / Engines

4 seats · 1 engine

Last airworthiness date

19710107

ADS-B equipped

Yes — Mode-S AAECE5

Registrant of record

LEWIS GARY DON

Source: FAA Aircraft Registry (releasable master file).

Aircraft involved

Probable cause & findings

The failure of the nose gear hydraulic flex line, which resulted in a loss of hydraulic fluid which prevented the main landing gear from fully extending and locking into place during landing.

Factual narrative

On August 15, 2021, about 1457 mountain daylight time, a Cessna C177RG, N8029G, was substantially damaged when it was involved in an accident at Albuquerque International Sunport Airport (ABQ), Albuquerque, New Mexico. The pilot was not injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. The pilot reported that, shortly after departure from St. Johns Industrial Air Park (KSJN), St Johns, Arizona, the airplane did not perform as expected. The pilot said that he noticed that the main landing gear did not completely retract, so he diverted to ABQ. Despite multiple attempts to cycle the landing gear, which included utilizing the emergency landing gear extension procedures, he was able to extend the nose landing gear, but he was unable to obtain a positive down and locked indication on the main landing gear. As fuel levels decreased, the pilot elected to land the airplane with the main landing gear in the retracted position. Postaccident examination of the airplane by a Federal Aviation Administration inspector revealed that hydraulic fluid on the undercarriage of the airplane behind the nose landing gear wheel well and the fluid level for the landing gear power pack indicated empty. Hydraulic fluid was added to the landing gear power pack and a landing gear swing test was performed. The landing gear extended but would not retract. The nose landing gear up hydraulic flex line showed signs of leakage. The hydraulic flex line was disconnected, and pressure tested with 200 ft pounds of nitrogen. A leak in the hydraulic flex line was identified near the top of the line, but well below the fitting. During normal operation, the hydraulic flex line is pressurized to about 1,500 ft pounds. No issues were noted with the emergency landing gear extension system. A review of the airplane’s maintenance records could not determine the age of the landing gear hydraulic flex line or if any maintenance had been performed on the landing gear hydraulic flex line. The pilot reported that, shortly after takeoff, the airplane was not performing as expected. He observed that the main landing gear did not fully retract so he diverted to a nearby airport. Despite multiple attempts to cycle the landing gear, which included utilizing the emergency landing gear extension procedures, he was able to extend the nose landing gear, but he was unable to obtain a positive down and locked indication on the main landing gear. As fuel levels decreased, the pilot landed the airplane with the main landing gear in the retracted position. A postaccident examination of the airplane revealed hydraulic fluid on the undercarriage of the airplane behind the nose landing gear wheel well. The nose landing gear up hydraulic flex line showed signs of leakage. The hydraulic flex line was disconnected, and pressure tested with 200 ft pounds of nitrogen. A leak in the hydraulic flex line was identified near the top of the line, but well below the fitting. It is likely that the identified leak in the hydraulic line led to a loss of hydraulic fluid and did not allow the main landing gear to extend and lock into place. As a result, the pilot made a gear up landing on the runway. Source: NTSB Aviation Accident Database Retrieved: 2026-02-12

NTSB Findings

Hierarchical cause / factor breakdown from the FAA bulk avdata database. Each finding tagged C (Cause) or F (Factor).

  • Aircraft-Aircraft systems-Hydraulic power system-(general)-Failure
  • Aircraft-Aircraft systems-Landing gear system-Main landing gear-Inoperative

Verbatim from NTSB's published report. Source file NTSB_2021_WPR21LA323.txt. Findings + structured fields enriched from FAA avall.mdb. Full investigation docket on data.ntsb.gov ↗.

Related research

What the literature says.

Academic papers and agency reports matching this event's aircraft type or causal vocabulary (maintenance). Sourced from NASA NTRS, NTSB Safety Studies, FAA CAMI, AOPA Air Safety Institute, Embry-Riddle Scholarly Commons, arXiv, and the Semantic Scholar academic graph.

Browse the full corpus — academia portal ↗