# NTSB ANC00LA092: Cessna 150F, N6296R, Anchorage, AK, July 20, 2000 - Type: NTSB accident investigation - Classification: Accident · Serious injuries · Limited investigation · Final report - Date: July 20, 2000, 12:30 local (20:30 UTC) - Place: Anchorage, AK - Coordinates: 61.160923, -149.990798 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=61.1609&lon=-149.9908&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Highest injury: Serious injuries - Injuries: 2 serious - Status: Completed, report July 10, 2001 - Report: Approved by Office Director - NTSB office: Alaska Regional Office - NTSB case key (mKey): 49807 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ANC00LA092 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/49807/pdf - Page: https://openairdocs.org/ntsb/ANC00LA092 ## Probable cause The failure of the pilot-in-command (CFI) to adequately supervise the instructional flight. Factors in the accident were an inadvertent spin entry by the student, and the pilot-in-command's failure to utilize adequate altitude for a stall demonstration. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of control - in flight, maneuvering - stall - intentional, pilot in command(cfi) - altitude - inadequate, pilot in command(cfi) (contributing factor) - stall/spin - inadvertent, dual student (contributing factor) - supervision - inadequate, pilot in command(cfi) (cause) - use of inappropriate medication/drug, pilot in command(cfi) - In flight collision with terrain/water, descent - uncontrolled - terrain condition - ground ## Analysis According to the first pilot, a flight instructor and owner of the accident airplane, he was providing flight instruction to his daughter in a float-equipped Cessna 150F airplane. He was demonstrating an approach to landing stall about 2,000 feet mean sea level. The airplane was configured with 20 degrees of flaps. When the airplane stalled, the student pilot cross-controlled the airplane. The left wing dropped and the airplane entered an uncommanded, inverted left spin. The instructor was able to recover the airplane to an upright attitude about 300 feet above the ground by adding engine power. The airplane continued to descend in a nose down attitude during the recovery, and struck the ground. The airplane had numerous modifications, including a 160 horsepower engine. The airplane had fixed floats installed, and qualified for the float installation when the previous owner/mechanic designated that the airplane be operated as a Cessna 150G. Changes from wheels to floats resulted in several configuration changes including propellers, and propeller spacers, larger wheels and tires, and the use of a heavier than normal nose wheel strut assembly. As a floatplane, the airplane was required to be operated in the normal category, with intentional spins prohibited. No data was available to the pilot about the consequences, or recovery techniques for an inadvertent spin. A center of gravity calculation of the accident flight placed the airplane within weight and balance limits. The presence of an over-the-counter antihistamine, and a prescription anti-depression medication, were found in the pilot's toxicological samples. ## Factual narrative HISTORY OF FLIGHT On July 20, 2000, about 1230 Alaska daylight time, a float-equipped Cessna 150F airplane, N6296R, sustained substantial damage when it collided with the ground, about 18 miles northwest of Anchorage, Alaska, about latitude 61 degrees, 21.47 minutes north, and longitude 150 degrees, 26.88 minutes west. The airplane was being operated as a visual flight rules (VFR) local area instructional flight, when the accident occurred. The airplane was owned and operated by the first pilot/flight instructor. The first pilot, seated in the right seat, and the student pilot, seated in the left seat, received serious injuries. Visual meteorological conditions prevailed. The flight originated at the Lake Hood Seaplane Base, Anchorage, about 1200. During an interview with a National Transportation Safety Board (NTSB) investigator on July 21, 2000, the first pilot reported that he was providing flight instruction to his daughter near the area of Figure Eight Lake. He said he was demonstrating an approach to landing stall about 2,000 feet mean sea level, and the student pilot was following on the controls. The airplane was configured with 20 degrees of flaps. The pilot said that when the airplane stalled, the student pilot cross-controlled the flight controls. The left wing dropped and the airplane entered an uncommanded, inverted left spin. The pilot said he attempted a variety of recovery techniques without success, but finally utilized full engine power to regain elevator authority. The pilot was able to recover the airplane to an upright attitude, and stop the spin about 300 feet above the ground. The airplane continued to descend in a nose down attitude during the recovery process, and struck the ground. AIRCRAFT INFORMATION The maintenance records of the accident airplane note numerous modifications that were accomplished before the pilot owned the airplane. An alteration to an aircraft requires a Federal Aviation Administration (FAA) Form 337, (major repair and alteration). An FAA airworthiness inspector's signature is not required on an FAA Form 337 if the repair or alteration is based on approved data, such as an approved supplemental type certificate (STC), or airworthiness directives (AD), or type certificate data sheets, etc. A major repair or alteration based on acceptable data, such as advisory circulars, manufacturer's technical data, or other FAA field approvals, etc., does require an inspector's signature. The maintenance records contain several FAA Form 337's with the date of March 31, 1993, as the date of alteration. Each of the reviewed 337's had an approval date for return to service, signed by the same mechanic who performed the alterations. The mechanic who performed the alterations holds an FAA Inspection Authorization (IA). The first Form 337 reflected installation of a nose wheel fork assembly from a Cessna 182, along with a 6.00 by 6 nose tire, and 8.50 by 6 main landing gear tires. A second FAA Form 337 reflected the installation of a Lycoming O-320 E2D engine (150 horsepower), in accordance with STC SA1034SW, issued to Air Mod Engineering, Oklahoma City, OK. This Form 337 was the only one without an airworthiness inspector's signature. STC SA1034SW is applicable to Cessna 150D through 150L models, and contains two limitations, one of which required a placard which states, "Intentional Spins Prohibited." The installation instructions also required the elimination of all references to spins on existing cockpit placards. Another Form 337 reflected work performed on April 21, 1993, to install a McCauley model 1C160/CTM 7553 propeller (for wheelplane operations), along with a machining of a propeller spacer and the installation of a propeller bolt kit. The installation of the nose fork, the propeller, and the Lycoming engine had a return to service date of April 23, 1993. A Form 337 with March 31, 1993, as the date of alteration, reflected a change from a Cessna 150F, to a Cessna 150G, and the installation of EDO 88A fixed floats. The language utilized on the Form 337, stated, in part: "Structurally and aerodynamically the 150F and the 150G are identical. The aircraft is to be operated as per the limitations for the 150G." The 337 included a reference to engineering drawings contained in STC SA1052SW, issued to Air Mod Engineering, for installing a Lycoming O-320 E2D engine, in accordance with STC SA1034SW, for Cessna 150G, 150H, and 150J floatplanes, and reflected a change from utility to normal category for a floatplane configuration. According to the Air Mod personnel, STC SA1052SW provides for the installation of an O-320 engine on floatplanes. The Cessna Aircraft Company reported that a 150F model Cessna is not eligible for the installation of fixed floats, but a 150G model is eligible for floats. Airplane type certificate data for a Cessna 150F, lists only landplane information with a maximum gross weight of 1,600 pounds. Type certificate data for a Cessna 150G, lists the same gross weight of 1,600 pounds for a landplane, and also lists gross weight data for a seaplane of 1,650 pounds. Another FAA Form 337, dated March 31, 1993, reflected the removal of a previously installed McCauley model 1C160/CTM propeller, and the installation of a McCauley model 1A175/ETM 8042 propeller (for floatplane operations). Alterations listed in this paragraph had a return to service date of June 8, 1993. A review of the accident airplane weight and balance data revealed that changes in the landing gear, (floats to wheels to floats) did not reflect the changes in propeller installations (each utilized different spacers and bolt kits), and the use of a heavier, Cessna 182 nose wheel strut. A weight and balance data sheet, completed July 28, 1993, reflected the installation of a float equipment kit, and a Lycoming O-320 engine. The computations were based on original aircraft data from June 23, 1965. The empty weight of the airplane was increased from 1,095.5 to 1,163.2 pounds, with a center of gravity of 33.29 inches. The maximum gross weight for a wheelplane, as stated on the form, was 1,600 pounds. A separate weight and balance data sheet for a floatplane indicated an empty weight of 1,264.7 pounds, with a center of gravity of 33.5 inches, with a floatplane gross weight of 1,700 pounds. On August 13, 1993, citing STC SA4795SW, the weight and balance data sheets reflected an increase in the gross weight of the airplane to 1,760 pounds. The empty weights and center of gravity for the wheelplane and floatplane configurations remained unchanged. According to Aircraft Conversion Technologies personnel, STC SA4795SW, kit number 287, was an upgrade package for airplanes that already had a 150 horsepower engine installed. The STC kit was sold to the airplane's previous owner/installer, in August, 1993. The upgrade package included a gross weight increase to 1,760 pounds, data sheets, and modifications to the engine cowl, nose bowl, and spinner. An FAA Form 337 was located in the maintenance records that documented the installation of a Lycoming O-320-E2D engine under STC SA4795SW. It had a date of alteration of October 24, 1995, with a return to service date of November 10, 1995. The 337 notes that "no flight manual supplement required as per STC SA4795SW." The 337 also states that the fuel fillers were placarded for 100/130 octane fuel, and the engine was converted to 160 horsepower in accordance with STC SE3692SW, which included the remarking of the engine tachometer. STC SA4795SW is currently owned by Aircraft Conversion Technologies Inc., Lincoln, California, for Cessna models 150, 150A thru 150M, A150K thru A150M, 152, and A152, for the installation of a Lycoming O-360 or O-320 engine, and an increase in airplane gross weight to 1,760 pounds. The STC contains limitations and conditions that state, in part, "Cessna model 150, 150A thru 150C, A150K thru A150M ## Aircraft - Registration: [N6296R](https://openairdocs.org/deregistered/N6296R-2003-10-25), registration cancelled 2003-10-25, S/N 15061596, built 1965 (OpenAirDocs) - Reported make and model: Cessna 150F - Registry model: [Cessna 150F](https://openairdocs.org/model/cessna-150f) (registry code 2071814) (OpenAirDocs) - Registry engine: [Continental 0-200 series](https://openairdocs.org/engine/continental-0-200-series) (registry code 17020, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 15061596 - Airframe hours: 4057 - Engines: Lycoming O-320-E2D 160 horsepower reciprocating - Damage: Substantial damage - Flight: Instructional, Part 91 - Operator: Craig L. Ketchum - Registered owner: Kal:Otter88ka, LLC - Airworthiness certificate: Standard, Utility; Standard, Normal - Last inspection: Annual, March 17, 2000, 20 hours before - Departed: PALH, ANCHORAGE, AK ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 49; flight instructor, commercial; airplane ratings: single-engine sea, single-engine land, multi-engine land; instrument ratings: airplane; medical: class 2, valid medical--no waivers/lim.; seat: right; toxicology performed; flight hours: 15,500 total, 100 in this make and model, 14,500 as pilot in command, 62 in the last 90 days, 15 in the last 30 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 296° at 5 knots - Visibility: 10 statute miles - Lowest ceiling: 6,000 ft broken - Temperature: 55 °F, dew point 50 °F - Altimeter: 29.00 inHg - Observed at: PAN, 18 nm away ## Other investigations on N6296R (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 ANC70D0091](https://openairdocs.org/ntsb/ANC70D0091), Dec 17, 1969: Cessna 150F (N6296R), Willow, AK, 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.