# NTSB FTW95LA237: Stokes Smith DSA-1, N33BS, Brookshire, TX, June 8, 1995 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Limited investigation · Final report - Date: June 8, 1995, 15:15 local (20:15 UTC) - Place: Brookshire, TX - Coordinates: 29.779571, -95.949829 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=29.7796&lon=-95.9498&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 November 8, 1995 - Report: Approved by Office Director - NTSB case key (mKey): 19448 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=FTW95LA237 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/19448/pdf - Page: https://openairdocs.org/ntsb/FTW95LA237 ## Probable cause OWNER/BUILDER'S INADEQUATE MAINTENANCE RESULTING IN A LOSS OF ENGINE POWER DUE TO CORRODED MAGNETO COILS. A FACTOR WAS THE LACK OF SUITABLE TERRAIN FOR THE FORCED LANDING. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of engine power(total) - mech failure/malf, takeoff - initial climb - ignition system,magneto - corroded (cause) - maintenance - inadequate, owner/builder (cause) - Forced landing, descent - emergency - On ground/water encounter with terrain/water, landing - roll - terrain condition - none suitable (contributing factor) - terrain condition - dirt bank/rising embankment ## Analysis THE PILOT REPORTED THAT THE ENGINE LOST POWER DURING THE INITIAL CLIMB AFTER TAKEOFF AND COLLIDED WITH A RICE LEVEE DURING THE FORCED LANDING. THE BUILDER/OWNER/PILOT HOLDS AN FAA AIRCRAFT REPAIRMAN CERTIFICATE AND PERFORMED THE MAINTENANCE ON THE AIRPLANE INCLUDING THE LAST ANNUAL INSPECTION THE DAY BEFORE THE ACCIDENT. THE FACTORY REMANUFACTURED MAGNETOS (BENDIX MODEL S4LN21 P/N 10- 51360-30; S/N 321336 AND 321337) HAD BEEN INSTALLED SINCE JUNE 10, 1988. FOLLOWING A LOSS OF ENGINE POWER, EXAMINATION OF THE MAGNETOS REVEALED 'HEAVILY CORRODED COILS.' THE LEFT MAGNETO COIL 'FAILED THE RESISTANCE CHECK.' GROUND LEAD TO HIGH TENSION RESISTANCE 'READ .85 OHM'; ACCORDING TO THE MANUFACTURER IT SHOULD READ '12,000 TO 16,000 OHMS.' THIS WAS THE PILOT'S 'THIRD FORCED LANDING DUE TO ENGINE FAILURE.' PRIOR TROUBLESHOOTING BY THE BUILDER DID NOT LEAD TO MAGNETO TEARDOWN. ## Factual narrative On June 8, 1995, at 1515 central daylight time, a Stokes, SMITH DSA-1, homebuilt airplane, N33BS, sustained substantial damage during a forced landing following a loss of engine power near Brookshire, Texas. The commercial pilot received minor injuries. Visual meteorological conditions prevailed for the local personal flight conducted under Title 14 CFR Part 91. During interviews, conducted by the Federal Aviation Administration (FAA) inspector, the pilot reported that after refueling, the flight departed a private airstrip near Waller, Texas, at 1525. A witness (statment enclosed) observed the airplane at 300 to 350 feet above the ground and "heard the aircraft mag cross firing." The pilot reported that the engine lost power. During the landing roll, the main gear hit a rice levee, the airplane cartwheeled and came to rest nose down. Horizontal stabilizer, vertical stabilizer, wing spars and engine components were damaged. A review of FAA records and the airplane maintenance logbooks revealed that the airplane was built by the current pilot/owner. Bendix model S4LN21 (P/N 10-51360-30) factory remanufactured left magneto (S/N 321336) and right magneto (S/N 321337) were installed on June 10, 1988. The airplanes's first flight was conducted on January 2, 1989, and on November 16, 1989, an FAA airworthiness certificate was issued without a geographic operation limitation. The builder holds an aircraft repairman certificate issued by the FAA on December 1, 1988. Records indicate that he performed the maintenance for N33BS including the last annual inspection on June 7, 1995. The magnetos were examined at C & D Aviation at Waller, Texas, and the FAA inspector reported that the teardown of the Bendix magnetos revealed that both magnetos had "heavily corroded coils." The left magneto coil "failed the resistance check." Ground lead to high tension resistance "read .85 ohm"; according to the manufacturer it should read "12,000 to 16,000 ohms." This was the pilot's "third forced landing due to engine failure" and prior troubleshooting by the builder did not lead to magneto teardown. Numerous attempts were made by the investigator-in-charge to obtain the Pilot/Operator Report (NTSB Form 6120.1/2). To date this report has not been received. ## Aircraft - Registration: [N33BS](https://openairdocs.org/deregistered/N33BS-1995-12-08), registration cancelled 1995-12-08, S/N 100 (OpenAirDocs) - Reported make and model: STOKES SMITH DSA-1 (SMITH DSA-) - Registry model: [Stokes William G SMITH DSA1](https://openairdocs.org/model/stokes-william-g-smith-dsa1) (registry code 8350257) (OpenAirDocs) - Category: Airplane, amateur-built - Serial number: 100 - Engines: LYCOMING O-320-A2B 150 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Registered owner: William G. Stokes - Airworthiness certificate: Special, Experimental (Special) - Last inspection: Annual, June 7, 1995 - Departed: NONE, WALLER, TX ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 74; commercial; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 3, valid medical--w/ waivers/lim; seat: center; flight hours: 3,300 total ## Weather - Conditions: Visual (VMC), Day - Wind: 150° at 15 knots - Visibility: 6 statute miles - Lowest ceiling: none - Temperature: 93 °F, dew point 73 °F - Altimeter: 29.00 inHg - Observed at: DWH, 20 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 19950608014409A](https://openairdocs.org/incident/19950608014409A), Jun 8, 1995: Amtrsm DSA1, Brookshire, TX, Substantial damage. Lost power on climbout. Hit levee landing worn corroded magnetos. Pilot mechanic had recently annualed the dsai. 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.