# NTSB ANC08LA030: Piper PA-22-150, N7637D, North Pole, AK, December 26, 2007 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: December 26, 2007, 15:58 local (19:58 UTC) - Place: North Pole, AK - Coordinates: 65.765274, -147.390548 - Nearby events: https://openairdocs.org/map.md?lat=65.7653&lon=-147.3905&mi=10 - Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed, report December 11, 2008 - Report: Approved by Office Director - NTSB office: Alaska Regional Office - Parties: Federal Aviation Administration - NTSB case key (mKey): 67442 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ANC08LA030 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/67442/pdf - Page: https://openairdocs.org/ntsb/ANC08LA030 ## Probable cause A loss of engine power for an undetermined reason during an attempted go-around, resulting in a forced landing and a collision with snow-covered terrain. A factor associated with the accident was the lack of suitable terrain for a forced landing. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of engine power, go-around (vfr) - reason for occurrence undetermined (cause) - Forced landing, emergency descent/landing - In flight collision with terrain/water, emergency landing - terrain condition - none suitable (contributing factor) ## Analysis A certificated flight instructor (CFI) was providing flight instruction to a student pilot during civil twilight. The CFI reported that while on approach to an unlighted, snow-covered gravel runway, he instructed the student pilot to go-around when he realized that the airplane was not lined up with the runway. He said that his verbal command to immediately applying full engine power and initiate a go-around was followed, but the engine did not respond. The CFI took control of the airplane, confirmed that the throttle was at maximum, and then he landed the airplane in the deep snow. As the main and nose wheels touched down in the deep snow, the airplane decelerated rapidly, and the nose landing gear collapsed. The airplane sustained substantial damage to the fuselage and wings. An FAA airworthiness inspector reported that his postaccident inspection of the airplane disclosed a number of maintenance deficiencies, but found none that would have accounted for the loss of engine power. ## Factual narrative On December 26, 2007, about 1558 Alaska standard time, a Piper PA-22-150 airplane, N7637D, sustained substantial damage during a forced landing following a reported loss of engine power while on approach to the Bradley Sky-Ranch Airport, North Pole, Alaska. The certificated flight instructor and the student pilot/airplane owner were not injured. The airplane was being operated as a visual flight rules (VFR) instructional flight under Title 14, CFR Part 91 when the accident occurred. Visual meteorological conditions prevailed at the time of the accident, and a VFR flight plan was in effect. The flight originated at the Fairbanks International Airport, Fairbanks, Alaska, about 1542. During a telephone conversation with the National Transportation Safety Board investigator-in-charge on January 29, the flight instructor reported that while on approach to runway 33, an unlighted, snow-covered gravel runway, he instructed the student pilot to go-around when he realized that the airplane was not lined up with the runway. He said that the student pilot followed his verbal command by immediately applying full engine throttle, but the engine did not respond. The instructor said that he then took control of the airplane, confirmed that the throttle was maximum, then pulled aft on the control yoke to cushion the landing on the snow-covered terrain. He said that when the main and nose wheels touched deep snow, the airplane decelerated rapidly, and the nose landing gear collapsed. The airplane sustained substantial damage to the fuselage and wings. The accident occurred during the hours of sunset, which began at 1444. Civil twilight for North Pole ended at 1608, or 10 minutes after the accident occurred. A Federal Aviation Administration (FAA) airworthiness inspector from the Fairbanks Flight Standards District Office (FSDO) responded to the accident scene shortly after the accident, and examined the airplane prior to recovery efforts. The inspector reported that during his inspection of the airplane, he noticed a placard on the airplane's instrument panel, mounted just above the engine throttle that said: "2 second delay, advance throttle slowly." In the flight instructor's written statement to the NTSB he noted that either carburetor icing, or an incorrect fuel mixture adjustment may have contributed to the loss of engine power. After the airplane was recovered from the accident site, the FAA inspector reported that throughout his postaccident inspection of the airplane he discovered a number of maintenance deficiencies, but found none that would have accounted for the loss of engine power. The closest weather observation facility is Fairbanks, which is 12 miles west of the accident site. On December 26, 2007, at 1553, an Aviation Routine Weather Report (METAR) was reporting, in part: Wind, 040 degrees at 4 knots; Visibility, 10 miles; ceiling, 4,100 feet broken; temperature, 0 degrees F; dew point, minus 8 degrees F; altimeter, 29.93 inHg. ## Aircraft - Registration: [N7637D](https://openairdocs.org/deregistered/N7637D-2018-02-20), registration cancelled 2018-02-20, S/N 22-5346, built 1957 (OpenAirDocs) - Reported make and model: PIPER PA-22-150 - Registry model: [Piper PA-22-150](https://openairdocs.org/model/piper-pa-22-150) (registry code 7102210) (OpenAirDocs) - Registry engine: [Lycoming 0-320 series](https://openairdocs.org/engine/lycoming-0-320-series) (registry code 41508, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 22-5346 - Airframe hours: 4913.5 - Engines: Lycoming O-320 150 horsepower reciprocating - Damage: Substantial damage - Flight: Instructional, Part 91 - Operator: Forest M. Kirst - Registered owner: Robert Allen & Gary Baumgartner - Airworthiness certificate: Standard, Normal - Last inspection: Annual, October 1, 2007, 35 hours before - Departed: FAI, FAIRBANKS, AK - Destination: FAI, FAIRBANKS, AK - Flight plan: VFR - Airport: 95Z, Bradley Sky-Ranch Airport, runway 33, 4,100 × 60 ft, snow ## Flight crew As NTSB recorded them. NTSB leaves out names. - Flight instructor; age 56; injuries: none; commercial, flight instructor; airplane ratings: single-engine land, single-engine sea; instrument ratings: airplane; medical: class 2, with waivers/limitations; last flight review August 1, 2007; seat: right; flight hours: 833 total, 30 in this make and model, 461 as pilot in command, 4 in the last 90 days, 13 in the last 30 days, 1 in the last 24 hours - Student pilot; age 56; injuries: none; student; medical: class 3, with waivers/limitations; seat: left; flight hours: 30 total, 20 in this make and model, 6 as pilot in command, 22 in the last 90 days, 9 in the last 30 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Dusk - Wind: 40° at 4 knots - Visibility: 10 statute miles - Lowest ceiling: 4,100 ft broken - Temperature: -0 °F, dew point -8 °F - Altimeter: 29.93 inHg - Observed at: PAFA, 12 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 20071226829429A](https://openairdocs.org/incident/20071226829429A), Dec 26, 2007: Piper PA22150, North Pole, AK, Substantial damage. (-23) During a practice VFR low approach to the left side off of runway 33 at Bradley field, North Pole Alaska, full power was applied for the go around. The… 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.