# NTSB ANC97TA152: Piper PA-18, N2355H, Coldfoot, AK, September 18, 1997 - Type: NTSB accident investigation - Classification: Accident · No injuries · Final report - Date: September 18, 1997, 13:30 local (21:30 UTC) - Place: Coldfoot, AK - Coordinates: 64.810867, -147.719802 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=64.8109&lon=-147.7198&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report November 6, 1998 - Report: Approved by Office Director - NTSB office: Alaska Regional Office - NTSB case key (mKey): 3086 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ANC97TA152 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/3086/pdf - Page: https://openairdocs.org/ntsb/ANC97TA152 ## Probable cause The overservicing/pressurizing of the hydraulic brake system by maintenance personnel that locked the brake system and prevented directional control. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of control - on ground/water, landing - flare/touchdown - landing gear,normal brake system - pressure excessive (cause) - maintenance,100-hour inspection - improper, other maintenance personnel (cause) - landing gear,normal brake system - locked (cause) - directional control - not possible, pilot in command - ground loop/swerve - inadvertent, pilot in command ## Analysis The airplane had just received a 100-hour inspection from a contract maintenance facility. The pilot was landing the tundra tire, tailwheel-equipped airplane on a gravel runway. During the flight, the pilot utilized a short section of tubing to direct heater air at his feet. During the landing touchdown, the pilot discovered the brakes were locked. The tires skidded on the gravel surface of the runway and the left wing struck the ground. The pilot indicated the brakes remained locked for about 2 hours after the accident. At that time, the wheels turned normally. The airplane utilizes a separate master brake cylinder/brake pedal assembly for each main wheel brake. The master cylinder/brake pedals are located on the cockpit floor, adjacent to the rudder pedals. The brake cylinders are normally serviced by adding hydraulic brake fluid through a small cap on the top of each cylinder. Maintenance personnel from the operator reported that overservicing of the brake cylinders, and heating of the cylinder assembly produced a locked brake condition. ## Factual narrative On September 18, 1997, about 1330 Alaska daylight time, a tundra tire equipped Piper PA-18, N2355H, crashed during landing at the Coldfoot Airport, Coldfoot, Alaska. The airplane was being operated as a visual flight rules (VFR) cross-country government flight under Title 14 CFR Part 91 when the accident occurred. The airplane, operated by the State of Alaska, Department of Public Safety, Division of Fish and Wildlife Protection, sustained substantial damage. The certificated private pilot, the sole occupant, was not injured. Visual meteorological conditions prevailed. VFR flight following procedures were in effect. The flight originated at the Fairbanks International Airport, Fairbanks, Alaska, about 1030. The operator reported the airplane had just received a 100 hour inspection from a contract maintenance facility in Fairbanks, Alaska, and the pilot was returning to his post in Coldfoot. During the flight, the pilot utilized a short section of tubing to direct heater air to his feet. The pilot landed on runway 19 at Coldfoot. When the airplane touched down, the pilot discovered the brakes were locked. The tires skidded on the gravel surface of the runway, and the left wing struck the ground. The pilot indicated the brakes remained locked for about 2 hours after the accident. At that time, the wheels turned normally. The airplane manufacturer reported the airplane utilizes a separate master brake cylinder/brake pedal assembly for each main wheel brake. The master cylinder/brake pedals are located on the cockpit floor, adjacent to the rudder pedals. The brake cylinders are normally serviced by adding hydraulic brake fluid through a small cap on the top of each cylinder. Maintenance personnel from the operator reported that over-servicing of the brake cylinders, and heating of the cylinder assembly produced a locked brake condition. ## Aircraft - Registration: [N2355H](https://openairdocs.org/aircraft/N2355H), registered now, S/N 18-7909175, built 1979 (OpenAirDocs) - Reported make and model: Piper PA-18 - Registry model: [Piper PA-18-150](https://openairdocs.org/model/piper-pa-18-150) (registry code 7101828) (OpenAirDocs) - Registry engine: [Lycoming 0-320 series](https://openairdocs.org/engine/lycoming-0-320-series) (registry code 41508, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 18-7909175 - Airframe hours: 2948 - Engines: Lycoming O-320-B2B 160 horsepower reciprocating - Damage: Substantial damage - Flight: Part 91 - Registered owner: State Of Alaska - Airworthiness certificate: Standard, Normal - Last inspection: 100 hour, September 16, 1997, 3 hours before - Departed: FAI, FAIRBANKS, AK - Destination: CXF - Flight plan: Company VFR - Airport: CXF, Coldfoot, runway 19, 4,000 × 100 ft, gravel ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 42; private; airplane ratings: single-engine sea, single-engine land; instrument ratings: airplane; medical: class 2, valid medical--w/ waivers/lim; seat: front; flight hours: 1,550 total, 1,100 in this make and model, 1,435 as pilot in command, 97 in the last 90 days, 40 in the last 30 days, 5 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 150° at 6 knots - Visibility: 40 statute miles - Lowest ceiling: 5,000 ft overcast - Temperature: 45 °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). - [Accident 19970918029279A](https://openairdocs.org/incident/19970918029279A), Sep 18, 1997: Piper PA18150, Coldfoot, AK, Substantial damage. (.4)The airplane had just received a 100-hour inspection from a contract maintenance facility. The pilot was landing the tundra tire, tailwheel-equipped… ## Other investigations on N2355H (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 ANC07TA093](https://openairdocs.org/ntsb/ANC07TA093), Sep 3, 2007: Piper PA-18-150 (N2355H), Valdez, AK, substantial damage. Probable cause: The pilot's selection of unsuitable terrain for takeoff. A factor contributing to the accident was an inadvertent stall/mush. 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.