# NTSB LAX97LA171: Cessna 140, N2031N, Palo Alto, CA, April 30, 1997 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Limited investigation · Final report - Date: April 30, 1997, 16:20 local (23:20 UTC) - Place: Palo Alto, CA - Coordinates: 37.449863, -122.100601 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=37.4499&lon=-122.1006&mi=10 - Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping) - Highest injury: Minor injuries - Injuries: 1 minor - Status: Completed, report May 21, 1998 - Report: Approved by Office Director - NTSB case key (mKey): 29781 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX97LA171 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/29781/pdf - Page: https://openairdocs.org/ntsb/LAX97LA171 ## Probable cause the pilot's failure to obtain and/or maintain adequate airspeed during initial climb after takeoff, which resulted in an inadvertent stall and collision with the terrain. A factor relating to the accident was: the degraded climb performance due to an unauthorized modification of the airplane, which increased the airplane's maximum fuel tank capacity and stall speed. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of control - in flight, takeoff - initial climb - fuel system - other - maintenance,modification - improper, company/operator management - aircraft performance,takeoff capability - impeded (contributing factor) - airspeed - not obtained/maintained, pilot in command (cause) - stall - inadvertent, pilot in command (cause) - In flight collision with terrain/water, descent - uncontrolled ## Analysis The pilot, who was the owner/operator of the airplane, applied engine power for takeoff, and the airplane accelerated and climbed approximately 50 feet above the runway. Suddenly, the airplane banked right, and the pilot attempted to lower the left wing by applying opposite aileron. His efforts were inadequate. He lost control of the airplane as the nose pitched down, and the airplane crashed. The airplane came to rest in an open dirt field about 150 feet from the runway's edge. The pilot reported that no mechanical malfunction or failures were experienced during the flight. An examination of the airplane revealed it had been modified by the addition of fuel tanks which increased the total fuel tank capacity from 25 gallons (standard) to about 60 gallons. The pilot reported that this modification, which was performed under his direction, had increased the airplane's stall speed by 6 mph. The FAA had not approved the modification. ## Factual narrative On April 30, 1997, at 1620 hours Pacific daylight time, a Cessna 140, N2031N, owned and operated by the pilot, crashed during an attempted takeoff from runway 30 at the Palo Alto Airport of Santa Clara County, Palo Alto, California. The airplane was destroyed, and the commercial pilot received minor injuries. Visual meteorological conditions prevailed during the personal flight, and no flight plan was filed. The flight was originating at the time of the accident. According to the pilot, he applied engine power and the airplane accelerated normally. Upon reaching an altitude approximately 50 feet above the runway, the airplane suddenly banked right. The pilot attempted to lower the left wing by applying opposite aileron. He stated that his efforts were not adequate, and he lost control of the airplane as the nose pitched down. The airplane's right wing and engine then contacted the ground. The engine separated from the airframe, and the propeller separated from the engine. The airplane came to rest in an upright attitude in an open dirt field about 150 feet from the runway's edge. The pilot reported that no mechanical malfunction or failures were experienced during the flight. The Federal Aviation Administration coordinator (FAA) examined the airplane wreckage. According to the FAA, the airplane's fuel system had been modified by the addition of outboard wing fuel tanks. The airplane's total fuel tank capacity had been increased from the standard 25 gallons to about 60 gallons. The pilot reported having about 55 gallons of fuel onboard during the attempted takeoff. This added capacity raised the airplane's gross weight, and the stall speed increased by 6 miles per hour. The pilot additionally reported to the FAA that the airframe modification had been performed under his direction. No logbook maintenance entries were found relating to the work. The FAA reported that it had not approved the modification. ## Aircraft - Registration: [N2031N](https://openairdocs.org/deregistered/N2031N-2013-08-07), registration cancelled 2013-08-07, S/N 12267, built 1947 (OpenAirDocs) - Reported make and model: Cessna 140 - Registry model: [Cessna 140](https://openairdocs.org/model/cessna-140) (registry code 2071602) (OpenAirDocs) - Registry engine: [Lycoming 0-290 series](https://openairdocs.org/engine/lycoming-0-290-series) (registry code 41506, 4 cycle) (OpenAirDocs) - Category: Airplane - Serial number: 12267 - Airframe hours: 2800 - Engines: Lycoming O-290 140 horsepower reciprocating - Damage: Destroyed - Flight: Personal, Part 91 - Registered owner: Lester J. Mattner - Airworthiness certificate: Standard, Normal - Last inspection: Annual, May 1, 1996 - Departed: PAO - Destination: 0O3, SAN ANDREAS, CA - Airport: PAO, Palo Alto, runway 30, 2,500 × 65 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 49; commercial; airplane ratings: single-engine land; medical: class 2, valid medical--w/ waivers/lim; seat: left; flight hours: 1,400 total, 1,400 in this make and model, 7 in the last 30 days ## Weather - Conditions: Visual (VMC), Day - Wind: 290° at 16 knots - Visibility: 15 statute miles - Lowest ceiling: 8,000 ft broken - Temperature: 66 °F, dew point 52 °F - Altimeter: 30.00 inHg - Observed at: PAO ## 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 19970430007179A](https://openairdocs.org/incident/19970430007179A), Apr 30, 1997: Cessna 140, Palo Alto, CA, Destroyed. Aircraft appeared to lose power on takeoff, turned right, crashed into a grassy area off right side of runway. (.4)the pilot, who was the owner/operator of… ## Other investigations on N2031N (2) 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 LAX76FUA27](https://openairdocs.org/ntsb/LAX76FUA27), Apr 27, 1976: Cessna 140 (N2031N), Dana Point, CA, substantial damage - [NTSB LAX71FUA40](https://openairdocs.org/ntsb/LAX71FUA40), Dec 11, 1970: Cessna 140 (N2031N), Long Beach, CA, 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.