# NTSB CHI98LA239: Robinson R-44, N8329B, Cassville, MO, July 2, 1998 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Limited investigation · Final report - Date: July 2, 1998, 14:15 local (19:15 UTC) - Place: Cassville, MO - Coordinates: 36.670566, -93.860252 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=36.6706&lon=-93.8603&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Highest injury: Minor injuries - Injuries: 2 minor - Status: Completed, report February 15, 2001 - Report: Approved by Office Director - NTSB case key (mKey): 10951 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CHI98LA239 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/10951/pdf - Page: https://openairdocs.org/ntsb/CHI98LA239 ## Probable cause The pilot in command's inadequate preflight planning/preparation and weather evaluation that resulted in flight into adverse weather conditions. Factors to the accident were a preflight briefing service not being used and the transmission wire. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - In flight collision with object, descent - preflight planning/preparation - inadequate, pilot in command (cause) - weather evaluation - inadequate, pilot in command (cause) - flight into adverse weather - encountered, pilot in command (cause) - preflight briefing service - not used, pilot in command (contributing factor) - object - wire,transmission (contributing factor) - Loss of control - in flight, descent - In flight collision with terrain/water, descent - uncontrolled ## Analysis The pilot and his passenger were enroute to their destination when they became aware that they were approaching a line of thunderstorms from behind. The pilot decided to make a precautionary landing due to the convective weather in the area and wait for the line of thunderstorms to move further from their route. During approach to the landing area, the aircraft struck a power line, approximately 35' above ground level (agl), and the pilot executed a run-on landing. The aircraft impacted the ground resulting in substantial damage to the landing skids, rotor blades, and tail boom. The pilot stated that he was aware of the thunderstorms from watching a television weather broadcast, but thought the line of storms had moved past his route of flight when he had made his departure. There were no Flight Service Station (FSS) or Direct User Access Terminal System (Duats) pilot briefings given for the aircraft in question. The pilot stated that there were no aircraft mechanical problems related to the accident. ## Factual narrative On July 2, 1998, at 1415 central daylight time (cdt), a Robinson R-44, N8329B, piloted by a private pilot, received substantial damage when it contacted wires and impacted the ground during a precautionary landing, in the Roaring River State Park, near Cassville, Missouri. The pilot stated that the precautionary landing was attempted due to deteriorating weather in the area, resulting from thunderstorms, lightning, and lowered visibility. Visual meteorological conditions prevailed at the time of the accident. The personal 14 CFR Part 91 flight was not operating on a flight plan. The pilot and one passenger reported minor injuries. The flight departed from a private helipad, near Tulsa, Oklahoma, at time unknown, with the intended destination of M. Graham Clark Airport, near Point Lookout, Missouri. According to the pilot's written statement, the pilot and his passenger were enroute to their destination when they became aware that they were approaching a line of thunderstorms from behind. The pilot stated that he decided to make a precautionary landing due to the convective weather in the area and wait for the line of thunderstorms to move further from their route. The pilot decided to land on a gravel bar in a river that ran through the Roaring River State Park. During approach to the landing area, the aircraft struck a power line, approximately 35' above ground level (agl), and the pilot executed a run-on landing. The aircraft impacted the ground resulting in substantial damage to the landing skids, rotor blades, and tail boom. In a telephone conversation with a Federal Aviation Administration (FAA) inspector, the pilot stated that he had asked his passenger to help him watch for wires, but he did not see them until it was too late to avoid them. The pilot stated that there were no aircraft mechanical problems related to the accident. The pilot stated, in a phone conversation with the Investigator in Charge (IIC), that he was aware of the thunderstorms from watching a television weather broadcast, but thought the line of storms had moved past his route of flight when he had made his departure. There were no Flight Service Station (FSS) or Direct User Access Terminal System (Duats) pilot briefings given for the aircraft in question. ## Aircraft - Registration: [N8329B](https://openairdocs.org/deregistered/N8329B-2003-12-24), registration cancelled 2003-12-24, S/N 0219, built 1995 (OpenAirDocs) - Reported make and model: Robinson R-44 - Registry model: [Robinson Helicopter R44](https://openairdocs.org/model/robinson-helicopter-r44) (registry code 7640120) (OpenAirDocs) - Registry engine: [Lycoming 0-540 series](https://openairdocs.org/engine/lycoming-0-540-series) (registry code 41532, reciprocating) (OpenAirDocs) - Category: Helicopter - Serial number: 0219 - Airframe hours: 700 - Engines: Lycoming VO-540 225 horsepower reciprocating - Damage: Substantial damage - Flight: Business, Part 91 - Registered owner: William Ray Stokely - Airworthiness certificate: Standard, Normal - Last inspection: 100 hour, March 24, 1998, 15 hours before - Departed: PVT, TULSA, OK - Destination: PLK, BRANSON, MO ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 55; private; medical: class 2, valid medical--w/ waivers/lim; seat: right; flight hours: 4,700 total, 4,700 as pilot in command, 38 in the last 90 days, 10 in the last 30 days ## Weather - Conditions: Visual (VMC), Day - Wind: 340° at 15 knots - Visibility: 8 statute miles - Lowest ceiling: 3,500 ft broken - Temperature: 73 °F, dew point 64 °F - Altimeter: 30.00 inHg - Observed at: ASG, 51 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 19980702015889A](https://openairdocs.org/incident/19980702015889A), Jul 2, 1998: Robsin R44, Cassville, MO, Substantial damage. Helicopter was attempting to land due to bad weather, struck a power line and crashed, Cassville, MO. (.4)the pilot and his passenger were enroute to their… ## Other investigations on N8329B (1) 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. - [NTSB LAX03LA235](https://openairdocs.org/ntsb/LAX03LA235), Jul 17, 2003: Robinson R44 (N8329B), Happy Jack, AZ, substantial damage. Probable cause: the partial loss of engine power due to an excessively lean mixture for undetermined reasons during cruise flight. 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.