Casualties unknown

Witness Reports No Engine Noise Before Airplane Collides with Water and Sinks (N7148L)

Lower Brule, SD, US

On August 10, 1997, a Grumman American AA-5 (registration N7148L) was involved in an aviation accident near Lower Brule, SD. Investigators recorded the probable cause as: undetermined due to the accident airplane not being available for examination. 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 witness observed an airplane flying low with no engine noise before it struck water, nosed over, and sank. The aircraft had departed with full fuel, and its estimated range far exceeded the distance flown. No debris, fuel, or oil slick was seen. The wreckage was not recovered.

Accident Overview

A witness fishing in the area reported that an airplane passed overhead at low altitude and produced no engine noise. The aircraft subsequently collided with the water, nosed over, and sank shortly thereafter. The event occurred after the airplane had departed an airport located approximately 180 miles from the accident site with a full fuel load.

Aircraft Performance Information

According to the pilot’s flight instructor, following a full fuel service, the airplane’s no‑wind range was estimated to be between 586 and 625 miles. The range varied depending on the altitude flown and the power setting selected. The distance from the departure airport to the accident location was well within that estimated range.

Post‑Accident Observations

Witnesses at the scene reported seeing no debris, fuel, or oil slick on the water where the airplane sank. Due to prevailing water conditions, the aircraft was not retrieved.

Frequently asked questions

What happened in the 10 Aug 1997 Grumman American AA-5 accident near Lower Brule, SD?

A witness observed an airplane flying low with no engine noise before it struck water, nosed over, and sank. The aircraft had departed with full fuel, and its estimated range far exceeded the distance flown. No debris, fuel, or oil slick was seen. The wreckage was not recovered.

What aircraft was involved and where did it happen?

The accident on 10 Aug 1997 involved a Grumman American AA-5, registration N7148L, at Lower Brule, SD.

What was the probable cause of the accident?

undetermined due to the accident airplane not being available for examination.

Investigation report by the U.S. National Transportation Safety Board (NTSB) historical archive. Original record: https://carol.ntsb.gov/event/20001208X08568. This page is a structured re-presentation; facts and quotes are in the National Transportation Safety Board (NTSB), United States.