# NTSB FTW95FA129: Cessna 208B, N9448B, Ardmore, OK, March 2, 1995 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Field investigation · Final report - Date: March 2, 1995, 08:15 local (14:15 UTC) - Place: Ardmore, OK - Coordinates: 34.189014, -97.110015 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=34.1890&lon=-97.1100&mi=10 - Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping) - Highest injury: Minor injuries - Injuries: 1 minor - Status: Completed, report November 30, 1995 - Report: Approved by Office Director - NTSB case key (mKey): 19214 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=FTW95FA129 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/19214/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=19214 - Page: https://openairdocs.org/ntsb/FTW95FA129 ## Probable cause THE PILOT'S CONTINUED FLIGHT INTO ADVERSE WEATHER CONDITIONS. FACTORS WERE THE ICING CONDITIONS PREVAILING AT THE DESTINATION AIRPORT, AND THE PILOT'S INABILITY TO MAINTAIN VISUAL LOOKOUT DUE TO WINDSHIELD ICING. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - In flight encounter with weather, approach - iaf to faf/outer marker (ifr) - weather condition - icing conditions (contributing factor) - weather condition - drizzle/mist (contributing factor) - flight into known adverse weather - continued, pilot in command (cause) - airframe - ice - level off - not possible, pilot in command (contributing factor) - window,flight compartment window/windshield - ice - visual lookout - not possible, pilot in command (contributing factor) - aircraft/equipment inadequate, manufacturer - In flight collision with terrain/water, emergency landing - flare - not possible, pilot in command ## Analysis STRUCTURAL ICE ACCUMULATED ON THE AIRPLANE AT A RAPID RATE WHILE THE PILOT WAS EXECUTING A PROCEDURE TURN DURING AN NDB APPROACH TO HIS DESTINATION AIRPORT. THE PILOT APPLIED MAXIMUM AVAILABLE POWER BUT WAS UNABLE TO ARREST THE RATE OF DESCENT. THE PILOT MAINTAINED 110 KNOTS DURING THE APPROACH AND AFTER BREAKING OUT INTO VISUAL CONDITIONS ELECTED TO PERFORM A FORCED LANDING IN AN OPEN FIELD 2 MILES SHORT OF THE DESTINATION AIRPORT. THE PILOT WAS UNABLE TO ARREST HIS DESCENT AND THE AIRPLANE IMPACTED THE GROUND IN A 5 DEGREE NOSE DOWN ATTITUDE. THE PILOT ALSO STATED THAT HIS FORWARD VISIBILITY WAS COMPLETELY OBSCURED BY THE ACCUMULATION OF CLEAR ICE ON THE WINDSHIELD. THE AIRPORT MANAGER INFORMED THE PILOT THAT FREEZING DRIZZLE WAS PRESENT AT THE AIRPORT WHEN THE PILOT CALLED THE UNICOM DURING THE INITIAL PORTION OF THE INSTRUMENT APPROACH. ## Factual narrative HISTORY OF FLIGHT On March 2, 1995, at 0815 central standard time, a Cessna 208B, N9448B, was substantially damaged during a forced landing near Ardmore, Oklahoma. The instrument rated commercial pilot suffered minor injuries. The airplane, operating under the callsign Martinaire 633, was owned by Cessna Finance Corporation, of Wichita, Kansas, and operated by MartinAire of Dallas, Texas. Instrument meteorological conditions prevailed for the 14 CFR Part 135 cargo flight. According to the operator, the airplane departed the Tulsa International Airport (TUL), at 0715 with a payload of 1,300 pounds of cargo, destined for the Ardmore Downtown Executive Airport (1F0). A weather briefing was received and an instrument flight plan filed. The pilot stated he was cleared for the NDB Runway 35 Approach to Ardmore while level at 5,000 feet. The pilot further stated that as he proceeded from the VOR to the NDB for the procedure turn, the airplane accumulated ice at a rapid rate. The pilot stated that he added maximum available power, as he continued to cycle the wing/strut deicing boots. The pilot stated that the airplane was configured with flaps up, airspeed at 110 knots when he broke out into visual conditions at approximately 400 feet AGL. The pilot further stated that he was unable to arrest the 400 to 500 fpm rate of descent to hold altitude. The airplane impacted in an open pasture in a nose low attitude. The nose landing gear separated, the mains collapsed, and the cargo pod was crushed. PERSONNEL INFORMATION The pilot who is home-based at Tulsa, Oklahoma, stated that he had been on duty since 2130 the previous night, and had flown a total of 4.2 hours during the same duty period. His last training session and check ride were completed on February 24, 1995. AIRCRAFT INFORMATION The 1988 model airplane was issued a normal category airworthiness certificate on September 22, 1988. The airplane was certified as a single pilot aircraft, certified for flights into known light to moderate icing conditions. The airplane was not equipped with deicing boots for the nosecap of the cargo pod or the landing gear struts. A review of the airframe and engine records by the FAA inspector, did not reveal any anomalies, uncorrected maintenance, or overdue airworthiness directives. All of the aircraft's deicing and anti-icing systems were reported as operational prior to the flight. The pilot had not reported any maintenance anomalies prior to the flight; however, during a post-accident interview the pilot stated that forward visibility through the detachable electric windshield anti-ice panel was inadequate, and his forward visibility was completely obscured by the accumulation of clear ice on the windshield. A review of the loading of the airplane revealed that at the time of the accident, the airplane was being operated within the prescribed weight and balance limits. METEOROLOGICAL INFORMATION The Automatic Weather Observation System (AWOS) weather report for Ardmore for 0700 CST was reported as sky partially obscured, 700 overcast, with a mile and a half visibility in drizzle. Temperature was 26 degrees, with a dew point of 25 degrees. The weather minimums for the NDB Runway 35 approach were 638 feet and 1 mile visibility. COMMUNICATIONS The pilot informed the airport manager on the Unicom frequency, that he had the current AWOS weather, and he was executing the NDB Runway 35 approach. The airport manager stated that he informed the pilot that freezing drizzle was present and the pilot acknowledged the transmission. His last radio transmission occurred when the pilot reported "procedure turn inbound" to the Unicom. WRECKAGE AND IMPACT INFORMATION The airplane impacted on an open pasture approximately 2 miles south of the approach end of runway 35, and one mile west of the extended centerline. Ground scars were found at the initial point of impact on a measured heading of 155 degrees. Chunks of rime and mixed ice contoured to the shape of several parts of the aircraft were found at the initial point of impact. The nose wheel strut and several other components associated with the nose wheel were found within 20 feet of the initial point of impact. After sliding for approximately 100 yards, the airplane came to rest on a measured magnetic heading of 330 degrees. All three composite blades separated at the hub. The spinner and hub assembly remained attached to the propeller shaft. The two main landing gears were found pushed aft and up, touching the respective wing strut. The belly cargo pod was crushed up and to the left. The wing flaps were found extended to 20 degrees. The elevator trim was found in the full nose up position. The engine inertial separator was found in the bypass mode. ADDITIONAL DATA The wreckage was released to the owner's representative on March 2, 1995, following completion of the field portion of the investigation. A teardown of the propeller was performed at the propeller manufacturer's facility. A copy of the examination report is enclosed. ## Aircraft - Registration: [N9448B](https://openairdocs.org/deregistered/N9448B-2020-07-27), registration cancelled 2020-07-27, S/N 208B0121, built 1988 (OpenAirDocs) - Reported make and model: CESSNA 208B - Registry model: [Cessna 208B](https://openairdocs.org/model/cessna-208b) (registry code 2073701) (OpenAirDocs) - Registry engine: [Pratt & Whitney PT6A series](https://openairdocs.org/engine/pratt-whitney-pt6a-series) (registry code 52032, turbo-prop) (OpenAirDocs) - Category: Airplane - Serial number: 208B0121 - Airframe hours: 3669 - Engines: P&W PT6A-114 600 horsepower turbo prop - Damage: Substantial damage - Flight: Part 135 - Operator: Martinaire Inc. - Registered owner: Cessna Finance Corp. - Airworthiness certificate: Standard, Normal - Last inspection: AAIP, December 15, 1994, 190 hours before - Departed: TUL, TULSA, OK - Destination: 1F0 - Flight plan: IFR ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 31; commercial, flight instructor; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 1, valid medical--no waivers/lim.; seat: left; flight hours: 4,374 total, 2,065 in this make and model, 4,110 as pilot in command, 180 in the last 90 days, 60 in the last 30 days, 4 in the last 24 hours ## Weather - Conditions: Instrument (IMC), Day - Visibility: 1.75 statute miles - Lowest ceiling: 700 ft overcast - Temperature: 27 °F, dew point 25 °F - Altimeter: 30.00 inHg ## 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 19950302004919A](https://openairdocs.org/incident/19950302004919A), Mar 2, 1995: Cessna 208B, Ardmore, OK, Substantial damage. Iced up on approach. Unable to arrest sink rate after breaking out of clouds. Impacted in pasture short of runway. ## Other investigations on N9448B (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 ANC19LA031](https://openairdocs.org/ntsb/ANC19LA031), Jul 8, 2019: Cessna 208 (N9448B), Bethel, AK, destroyed. Probable cause: The pilot’s failure to maintain adequate airspeed while maneuvering during an attempted go-around, which resulted in an exceedance of the airplane's critical angle of attack and an aerodynamic stall… ## Docket (16 files) The files NTSB released with the investigation on October 19, 1995, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=19214. 1.9 MB in all. - Supplement A (item 1, .PDF, 195 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40033190&FileExtension=.PDF&FileName=Supplement%20A-Master.PDF - Supplement B (item 2, .PDF, 293 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40033191&FileExtension=.PDF&FileName=Supplement%20B-Master.PDF - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 3, .PDF, 348 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40401616&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF - Witness Statement (item 4, .PDF, 57 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40401618&FileExtension=.PDF&FileName=Witness%20Statement-Redacted.PDF - Maps or Charts of Accident Area (item 5, .PDF, 60 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40033194&FileExtension=.PDF&FileName=Maps%20or%20Charts%20of%20Accident%20Area-Master.PDF - Weather Reports and Records (item 6, .PDF, 62 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40033195&FileExtension=.PDF&FileName=Weather%20Reports%20and%20Records-Master.PDF - Reports from Federal Agencies (item 7, .PDF, 27 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40401620&FileExtension=.PDF&FileName=Reports%20from%20Federal%20Agencies-Redacted.PDF - Other Pertinent Forms and Reports (item 8, .PDF, 227 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40033197&FileExtension=.PDF&FileName=Other%20Pertinent%20Forms%20and%20Reports-Master.PDF - Statement of Party Representatives to NTSB Investigation (item 9, .PDF, 289 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40401622&FileExtension=.PDF&FileName=Statement%20of%20Party%20Representatives%20to%20NTSB%20Investigation-Redacted.PDF - Release of Aircraft Wreckage, NTSB Form 6120.15 (item 10, .PDF, 82 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40401623&FileExtension=.PDF&FileName=Release%20of%20Aircraft%20Wreckage,%20NTSB%20Form%206120.15-Redacted.PDF - Photo 1: Left view of wreckage. (item 11, .PDF, 32 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40033200&FileExtension=.PDF&FileName=Photo%201%3A%20%20Left%20view%20of%20wreckage.-Master.PDF - Photo 2: Right frontal view of the wreckage. (item 12, .PDF, 39 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40033201&FileExtension=.PDF&FileName=Photo%202%3A%20%20Right%20frontal%20view%20of%20the%20wreckage.-Master.PDF - Photo 3: Close-up of the right front side of the wreckage. (item 13, .PDF, 30 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40033202&FileExtension=.PDF&FileName=Photo%203%3A%20%20Close-up%20of%20the%20right%20front%20side%20of%20the%20wreckage.-Master.PDF - Photo 4: Close-up of the left wing strut and tie down ring. (item 14, .PDF, 28 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40033203&FileExtension=.PDF&FileName=Photo%204%3A%20%20Close-up%20of%20the%20left%20wing%20strut%20and%20tie%20down%20ring.-Master.PDF - Photo 5: Ground scars at the accident site with wreckage in background. (item 15, .PDF, 51 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40033204&FileExtension=.PDF&FileName=Photo%205%3A%20%20Ground%20scars%20at%20the%20accident%20site%20with%20wreckage%20in%20background.-Master.PDF - Photo 6: Chunks of ice found at the initial point of impact. (item 16, .PDF, 53 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40033205&FileExtension=.PDF&FileName=Photo%206%3A%20Chunks%20of%20ice%20found%20at%20the%20initial%20point%20of%20impact.-Master.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.