No fatalities

Landing Gear Collapse After Diversion Due to Oil Pressure and Gear Indicator Issue (N9724B)

Fort Smith, AR, US

On September 12, 1999, a Cessna 172RG (registration N9724B) operated by Flight Works Inc. was involved in an aviation accident near Fort Smith, AR. No fatalities were reported. Investigators recorded the probable cause as: The failure of the electric pump motor/hydraulic power pack resulting in the collapse of the right main landing gear upon landing. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.

Sourcesthe U.S. National Transportation Safety Board (NTSB) historical archivePrimary reportUpdated 2026-07-04Data APIEditorial standards

A pilot diverted to Fort Smith, Arkansas, after oil pressure exceeded limits and landing gear indicator light failed. Tower confirmed gear extended but not locked; upon landing, right main gear collapsed. Investigation found electric pump motor/hydraulic power pack failure.

Incident Overview

The right main landing gear of an airplane collapsed during landing after the pilot diverted to Fort Smith, Arkansas. The pilot was operating under an IFR flight plan from Oklahoma City, Oklahoma, to Little Rock, Arkansas. During the flight, the pilot observed that the oil pressure exceeded the green range and subsequently diverted to Fort Smith.

Landing Gear Extension Issue

When the pilot extended the landing gear, the indicator light did not illuminate. To assess the gear position, the pilot performed a low flyby over the airport, allowing controllers in the control tower to visually inspect the landing gear. The tower controllers confirmed that the gear appeared to be extended but could not determine whether it was locked in position.

Landing and Failure

Upon landing, the right main landing gear collapsed. Post-incident examination of the airplane revealed that the electric pump motor/hydraulic power pack had failed. The component was replaced, and following replacement, the landing gear system operated within manufacturer's specifications.

Frequently asked questions

What happened in the 12 Sept 1999 Cessna 172RG accident near Fort Smith, AR?

A pilot diverted to Fort Smith, Arkansas, after oil pressure exceeded limits and landing gear indicator light failed. Tower confirmed gear extended but not locked; upon landing, right main gear collapsed. Investigation found electric pump motor/hydraulic power pack failure.

Were there any fatalities in the 12 Sept 1999 Cessna 172RG accident?

No fatalities were recorded in this accident.

What aircraft was involved and where did it happen?

The accident on 12 Sept 1999 involved a Cessna 172RG, registration N9724B, operated by Flight Works Inc., at Fort Smith, AR.

What was the probable cause of the accident?

The failure of the electric pump motor/hydraulic power pack resulting in the collapse of the right main landing gear upon landing.

Investigation report by the U.S. National Transportation Safety Board (NTSB) historical archive. Original record: https://carol.ntsb.gov/event/20001212X19767. This page is a structured re-presentation; facts and quotes are in the National Transportation Safety Board (NTSB), United States.