# NTSB LAX98IA097: Beech BE99, N20FW, Oakland, CA, February 24, 1998 - Type: NTSB incident investigation - Classification: Incident · No injuries · Incident investigation · Final report - Date: February 24, 1998, 11:41 local (19:41 UTC) - Place: Oakland, CA - Coordinates: 37.770366, -122.209136 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=37.7704&lon=-122.2091&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report February 16, 2001 - Report: Approved by Office Director - NTSB case key (mKey): 29967 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX98IA097 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/29967/pdf - Page: https://openairdocs.org/ntsb/LAX98IA097 ## Probable cause Water accumulation in the tail section of the aircraft that froze around the elevator control cables which restricted the movement of the elevator. Contributing factors were the accumulation of debris in the limbers and drain hole for the affected area. A finding was the fact that this area cannot be easily inspected by the pilot due to the need for hand tools to gain visual access. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of control - in flight, cruise - elevator - restricted, pilot in command - weather condition - icing conditions (contributing factor) - fluid,water - flow restricted (contributing factor) - fluid,water - frozen (cause) - Forced landing, cruise - precautionary landing - performed, pilot in command ## Analysis The aircraft encountered elevator control problems while en route and landed safely at his destination. During a post-landing inspection, ice formation was found in the tail section of the aircraft in an area surrounding the elevator control cables. The water drain hole and limbers that evacuate this area were found clogged with fuzz-like fibers. ## Factual narrative On February 24, 1998, at 1141 hours Pacific standard time, the airline transport pilot of a Beech BE99, N20FW, encountered elevator control problems and landed safely at his destination. There was no aircraft damage or injury to the pilot, the sole occupant. The flight departed from Burbank, California, on a 14 CFR Part 135 air cargo flight to Oakland, California, and was being operated by Ameriflight, Incorporated, on an instrument flight plan. Visual meteorological conditions prevailed for the landing site. During a postflight inspection, ice was observed in the tail section of the fuselage in an area that surrounded the elevator control cables. The "limbers" and water drain hole that evacuate this area were found clogged with small "fuzz-like" fibers. (See the sketch in Section 10.00 attached to this report.) ## Aircraft - Registration: [N20FW](https://openairdocs.org/aircraft/N20FW), registered now, S/N U-111, built 1969 (OpenAirDocs) - Reported make and model: Beech BE99 - Registry model: [Beech B-99](https://openairdocs.org/model/beech-b-99) (registry code 1154004) (OpenAirDocs) - Registry engine: [U/A Canada PT6 SER 578HP](https://openairdocs.org/engine/u-a-canada-pt6-ser-578hp) (registry code 61501, turbo-prop) (OpenAirDocs) - Category: Airplane - Serial number: U-111 - Engines: U/A Canada PT6 SER 578HP 550 horsepower turbo prop - Damage: No damage - Flight: Part 135 - Operator: Ameriflight, Inc. - Registered owner: National Leasing Corp - Airworthiness certificate: Standard, Normal - Departed: BUR, BURBANK, CA - Destination: OAK, OAKLAND, CA - Flight plan: IFR ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 29; airline transport, flight instructor; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 1, valid medical--w/ waivers/lim; seat: left; flight hours: 5,000 total, 300 in this make and model ## Weather - Conditions: Visual (VMC), Day - Visibility: 20 statute miles - Lowest ceiling: none - Temperature: 16 °F ## FAA reports on this event (1) The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs). - [Incident 19980224012269I](https://openairdocs.org/incident/19980224012269I), Feb 24, 1998: Beech 99, Oakland, CA. Narrative: on February 24, 1998, Mr. Jason p. doyle was the pilot in command of Beechcraft BE-99, N20FW, (amflight 125). Amflight 125 was on an IFR flight from… ## Other investigations on N20FW (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 SEA75FYG18](https://openairdocs.org/ntsb/SEA75FYG18), Feb 4, 1975: Beech 99A (N20FW), Pullman, WA, substantial damage 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.