# NTSB CHI97LA114: Olsen Acro Sport II, N52260, Monon, IN, April 27, 1997 - Type: NTSB accident investigation - Classification: Accident · Serious injuries · Limited investigation · Final report - Date: April 27, 1997, 10:33 local (14:33 UTC) - Place: Monon, IN - Coordinates: 40.859699, -86.869163 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=40.8597&lon=-86.8692&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Highest injury: Serious injuries - Injuries: 2 serious - Status: Completed, report February 28, 2000 - Report: Approved by Office Director - NTSB case key (mKey): 10552 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CHI97LA114 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/10552/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=10552 - Page: https://openairdocs.org/ntsb/CHI97LA114 ## Probable cause The loss of engine power for undetermined reasons. Low altitude flight is a contributing factor. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of engine power, maneuvering - reason for occurrence undetermined, pilot in command (cause) - Forced landing, maneuvering - In flight collision with object, descent - emergency - object - tree(s) - low altitude flight/maneuver - performed, pilot in command (contributing factor) - In flight collision with terrain/water, descent - uncontrolled ## Analysis Witnesses reported seeing the airplane flying at an altitude of less than 200 feet above the ground just prior to the accident. They stated the airplane banked between 45 and 80 degrees and descended into the trees prior to contacting the terrain. In addition, witnesses reported hearing a loss of engine power just prior to the airplane contacting the trees. ## Factual narrative On April 27, 1997 at 1033 eastern daylight time (edt), a Acro Sport II, N52260, was substantially damaged near Monon, Indiana. The pilot was reported to be flying at low altitude when witnesses reported the airplane sustained a loss of power. One witness believed that the airplane was less than 200 feet above the ground when the loss of power occurred. After the loss of power the airplane contacted trees, and collided with the terrain during an uncontrolled descent. The commercial rated pilot, and passenger were seriously injured in the accident. The 14 CFR Part 91 flight was operating in visual meteorological conditions, and no flight plan had been filed. A post flight examination of the airplane was conducted by a representative from the Federal Aviation Administration (FAA). The representative reported that at least two witnesses to the accident reported that the engine sustained a loss of power prior to impact. The representative reported that the airplane's propeller blades were both straight, and showed no signs of chordwise scratching. The representative stated that one witnesses went up to the airplane following the accident and used dirt to plug a fuel line which was leaking fuel. No flight control abnormalities were reported by the FAA representative. The airplane was removed from the accident site and was stored at a private airstrip. Before the airplane's engine was examined by a representative of the FAA or the IIC the aircraft wreckage was released to the son of the pilot of the airplane, who removed the airplane and engine from the private airstrip. The IIC left messages on the sons answering machine, and sent certified letters requesting an inspection of the aircraft's engine. No correspondence was received by the IIC from the son of the pilot. ## Aircraft - Registration: [N52260](https://openairdocs.org/deregistered/N52260-2013-08-06), registration cancelled 2013-08-06, S/N 384, built 1984 (OpenAirDocs) - Reported make and model: OLSEN ACRO SPORT II (ACRO SPORT) - Registry model: [Olsen James M ACRO SPORT II](https://openairdocs.org/model/olsen-james-m-acro-sport-ii) (registry code 05655QG) (OpenAirDocs) - Registry engine: [Lycoming 0-320 series](https://openairdocs.org/engine/lycoming-0-320-series) (registry code 41508, reciprocating) (OpenAirDocs) - Category: Airplane, amateur-built - Serial number: 384 - Engines: Lycoming O-235 115 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Operator: Charles H. Klopfenstein - Registered owner: Chris G. Walter - Airworthiness certificate: Special, Experimental (Special) - Departed: UNKNOWN ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 53; commercial; airplane ratings: single-engine land; seat: rear; flight hours: 5,000 total ## Weather - Conditions: Visual (VMC), Day - Wind: variable at 6 knots - Visibility: 8 statute miles - Lowest ceiling: 6,500 ft overcast - Temperature: 55 °F, dew point 39 °F - Altimeter: 29.00 inHg - Observed at: LAF, 30 nm away ## FAA reports on this event (1) The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs). - [Accident 19970427006609A](https://openairdocs.org/incident/19970427006609A), Apr 27, 1997: Amtr ACROSPORT, Monon, IN, Substantial damage. Aircraft lost power, clipped trees, crashed in a wheat field. (-23)aircraft lost power while in a steep turn and struck tree tops. The aircraft then impacted… ## Docket (2 files) The files NTSB released with the investigation on June 28, 2023, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=10552. 173 KB in all. - Supplement s (item 1, PDF, 1 page, 64 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=15372483&FileExtension=pdf&FileName=Supplement%20S-Master-Rel.pdf - Witness statements (item 2, PDF, 2 pages, 109 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=15371729&FileExtension=pdf&FileName=Witness%20Statements-Master-Rel.pdf From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.