# NTSB ANC99FA074: Piper PA-31-350, N41078, Tanana, AK, June 11, 1999 - Type: NTSB accident investigation - Classification: Accident · Fatal · Field investigation · Final report - Date: June 11, 1999, 07:23 local (15:23 UTC) - Place: Tanana, AK - Coordinates: 65.179054, -152.069946 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=65.1791&lon=-152.0699&mi=10 - Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping) - Highest injury: Fatal - Injuries: 1 fatal - Status: Completed, report November 2, 2000 - Report: Approved by Office Director - NTSB office: Alaska Regional Office - NTSB case key (mKey): 46563 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ANC99FA074 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/46563/pdf - Page: https://openairdocs.org/ntsb/ANC99FA074 ## Probable cause Undetermined. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of engine power, takeoff - initial climb - 1 engine - reason for occurrence undetermined (cause) - Forced landing, emergency landing after takeoff - In flight collision with object, emergency landing after takeoff - object - tree(s) - In flight collision with terrain/water, descent - uncontrolled - terrain condition - water ## Analysis A twin-engine airplane on a scheduled passenger/cargo flight, departed a rural airport located along the north shore of the Yukon River with only the pilot aboard. The airplane appeared to depart normally, but remained low, flying over the river, about 200 feet above the ground. About five minutes after departure, the pilot contacted a local weather observation facility on the common traffic advisory frequency (CTAF), and reported he was having a problem with the airplane, stating he may have to ditch. He did not describe the nature of the problem. The pilot then said he was clipping trees, and was attempting to return to the runway. The airplane collided with several trees located on a gravel bar in the Yukon River, separating the outboard end of the left wing. The airplane then collided with the river and sank, about 1.5 miles south of the airport. A fast river current, and silty water conditions hampered recovery efforts, but the left wing, the left engine, and the fuselage were recovered from the river. The left engine propeller appeared to be feathered. The right wing and the right engine were not recovered. Postaccident examination of the left engine disclosed no evidence that it was producing power upon impact, or any evidence of any preimpact mechanical malfunction. Inspection of the airframe disclosed no evidence of any preimpact mechanical malfunction. ## Factual narrative HISTORY OF FLIGHT On June 11, 1999, about 0723 Alaska daylight time, a Piper PA-31-350 airplane, N41078, was destroyed by impact with trees and the Yukon River, about 1.5 miles southwest of Tanana, Alaska. The airplane was being operated as Flight 1604 from Fairbanks, Alaska, to Tanana, to Galena, Alaska, as a visual flight rules (VFR) scheduled passenger/cargo flight under Title 14, CFR Part 135. The airplane was operated by Larry's Flying Service Inc., Fairbanks. The certificated airline transport pilot, the sole occupant, received fatal injuries. Visual meteorological conditions prevailed. VFR company flight following procedures were in effect. Flight 1604 departed Fairbanks about 0631 and was carrying cargo only. The flight landed at the Ralph M. Calhoun Memorial Airport, Tanana about 0712. According to the operator's records, 109 pounds of cargo was unloaded. About 1,236 pounds of cargo remained on the airplane. The airplane departed runway 24 about 0718 for Galena. A witness at the airport saw the airplane arrive in Tanana. He said the engines sounded normal. When the engines were started for departure, he noted the right engine was started first after extended cranking. Once started, the right engine ran at a high idle. The left engine was then immediately started. It ran at a lower rpm, and sounded normal. The witness saw the airplane depart, and said that after the landing gear retracted, the airplane leveled off and stayed low over the river. The airplane turned to follow the Yukon River instead of climbing. A village agent for the operator reported he heard the airplane arrive in Tanana, and it sounded normal. He departed the airport before the airplane took off. About five minutes after he left the airport, he heard a loud noise from the river area. He heard a loud bang, followed by a loud screeching noise, and then quiet. About five minutes after departure, the pilot contacted a local weather observation service at Tanana on the common traffic advisory frequency (CTAF). The pilot radioed that he was having a problem with the airplane, and stated he may have to ditch. He did not describe the nature of the problem. About 15 seconds later, the pilot radioed that he was over the river, the airplane was clipping trees, and he was attempting to return to the runway. The airplane collided with several trees located on a small island in the Yukon River, separating the outboard end of the left wing. The airplane then collided with the water and sank. The accident occurred during the hours of daylight at latitude 65 degrees, 09.5 minutes north, and longitude 152 degrees, 09.4 minutes west. CREW INFORMATION The pilot held an airline transport pilot certificate with an airplane multiengine land rating. He held commercial pilot privileges with airplane single-engine land and sea ratings. The most recent first-class medical certificate was issued to the pilot on February 25, 1999, and contained no limitations. The pilot was an enlisted member of the U.S. Air Force. His previous 72 hour military schedule was provided by personnel from the Eielson Air Force Base, Fairbanks. The pilot was on duty with the Air Force from 1800, June 7, to 0600, June 8. He was scheduled to be off duty from June 9, to June 11. According to flight and duty records provided by the operator, the pilot logged 2.4 hours of flight time for the operator on June 9, from 0830 to 1100. On June 10, he logged 4.3 hours from 0630 to 1330. His anticipated flight time on June 11, was to be a repeat of the previous day. The pilot's personal flight logs were not located. The pilot was hired by the operator on March 7, 1996. According to the operator, the pilot had accrued 3,226.7 hours of total experience, 861.2 of which were in the accident airplane make and model. In the previous 12 months before the accident, the pilot accrued 826.7 hours, of which 611.2 were in the accident airplane make and model. In the previous 30 days, the pilot accrued 51.2 hours, and 48.7 in the accident airplane. In the previous 24 hours, the pilot accrued 5.3 hours in the accident airplane. AIRCRAFT INFORMATION The airplane was maintained on a phase inspection program, as part of a Federal Aviation Administration (FAA) approved aviation inspection program (AAIP). A complete inspection of the airplane consists of four event inspections, each accomplished every 55 hours, for a total of 220 hours for the entire cycle. A complete inspection cycle is required to be accomplished within a 12 calendar month period, and qualifies as an annual inspection for the airplane. Each event inspection consists of detail items, and routine items. According to the AAIP, A routine inspection consists of a visual examination or check of items, as practical, without disassembly. A detailed inspection consists of an examination necessitating disassembly of items, as required. Each event inspection includes maintenance discrepancy items that are in addition to those specifically listed in the AAIP. The most recent inspection of the airplane was an Event Four inspection, conducted on June 4, 1999. The inspection consisted of a detailed inspection of the right engine, the right propeller, the right engine turbocharger, and the landing gear. A routine inspection of the left engine, the left propeller, the left engine turbocharger, and fuselage, was also part of the Event Four inspection. At the last inspection, the airplane had accrued 15,208.9 hours total time. The left and right engines had 1290.3 hours since overhaul. Both engines were overhauled by the operator on February 14, 1998. The left propeller had accrued 2128.6 hours since overhaul. The right propeller had accrued 1871.8 hours since overhaul. Since the last inspection, until the airplane departed for Tanana on the day of the accident, the airplane accrued an additional 20.5 hours. Examination of the maintenance records revealed no uncorrected discrepancies since the last inspection. Examination of the maintenance records disclosed several fuel system related discrepancies from January 1999, to June, 1999. During an Event Four inspection on January 4, 1999, the right engine fuel pump had evidence of a slight leak. It was retorqued. The right wing fuel sump drain was leaking. The sump valve was replaced. During an Event One inspection on January 22, 1999, the airplane fuel regulator was leaking. It was replaced. During an Event Two inspection on February 22, 1999, fuel stains were noted in the left engine accessory section. The fuel line to the fuel pump was tightened. During an Event Three inspection on March 18, 1999, the right engine's number one cylinder induction tube had signs of a fuel leak. New gaskets were installed. During an Event Four inspection on April 6, 1999, the right engine fuel pump had signs of fuel leaking around the adjustment head. The pump was retorqued. The left engine fuel pump had signs of fuel staining. A fitting on the pump was cleaned and resealed. During an Event Two inspection on May 6, 1999, a fuel leak was noted on the number 2 cylinder on the left engine. A bolt was replaced on the intake pipe flange. The fuel line to the airplane heater had signs of fuel staining. The fuel line fitting was tightened. During an Event Three inspection on May 23, 1999, the number three and number five cylinder induction tubes on the right engine were leaking. The gaskets were replaced. The maintenance records note that during the Event Four inspection on April 6, 1999, a discrepancy was noted that stated, "left engine - wrench sticking out of engine by alternator." The sign-off for the discrepancy was, "removed wrench and returned to proper location." The pilot's operating handbook for the accident airplane specifies the use of zero flaps for a normal takeoff, and 15 degrees of flaps for a short field takeoff. After takeoff, the flap ## Aircraft - Registration: [N41078](https://openairdocs.org/deregistered/N41078-2000-05-04), registration cancelled 2000-05-04, S/N 31-8352017 (OpenAirDocs) - Reported make and model: Piper PA-31-350 - Registry model: [Piper PA-31-350](https://openairdocs.org/model/piper-pa-31-350) (registry code 7103110) (OpenAirDocs) - Category: Airplane - Serial number: 31-8352017 - Airframe hours: 15229 - Engines: Lycoming TIO-540-J2BD 350 horsepower reciprocating - Damage: Destroyed - Flight: Part 135 - Operator: Larry'S Flying Service Inc. - Registered owner: Chartercraft Leasing - Airworthiness certificate: Standard, Normal - Last inspection: AAIP, June 4, 1999, 21 hours before - Departed: PATA - Destination: PAGA, GALENA, AK - Flight plan: Company VFR - Airport: PATA, Tanana ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 37; airline transport, commercial; airplane ratings: single-engine sea, single-engine land, multi-engine land; instrument ratings: airplane; medical: class 1, valid medical--no waivers/lim.; seat: left; toxicology performed; flight hours: 3,227 total, 861 in this make and model, 52 in the last 30 days ## Weather - Conditions: Visual (VMC), Day - Wind: calm - Visibility: 40 statute miles - Lowest ceiling: none - Temperature: 55 °F, dew point 48 °F - Altimeter: 29.00 inHg - Observed at: PAT, 1 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 19990611021989A](https://openairdocs.org/incident/19990611021989A), Jun 11, 1999: Piper PA31350, Tanana, AK, Destroyed, 1 fatal. (.19) On June 11, 1999, about 0723 Alaska daylight time, a Piper PA-31-350 airplane, N41078, was destroyed by impact with trees and the yukon river, about 1.5… ## Other investigations on N41078 (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 ANC86IA069](https://openairdocs.org/ntsb/ANC86IA069), Jun 10, 1986: Piper PA-31-350 (N41078), Nulato, AK, incident, minor 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.