# NTSB LAX90LA221: Grumman G21A, N86640, Long Beach, CA, June 16, 1990 - Type: NTSB accident investigation - Classification: Accident · Serious injuries · Limited investigation · Final report - Date: June 16, 1990, 13:30 local (20:30 UTC) - Place: Long Beach, CA - Coordinates: 33.810718, -118.180709 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=33.8107&lon=-118.1807&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Highest injury: Serious injuries - Injuries: 1 serious, 1 minor - Status: Completed, report June 8, 1993 - Report: Approved by Office Director - NTSB case key (mKey): 26841 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX90LA221 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/26841/pdf - Page: https://openairdocs.org/ntsb/LAX90LA221 ## Probable cause THE PILOT'S FAILURE TO RETRACT THE LANDING GEAR RESULTING IN AN INADVERTENT WHEELS-DOWN LANDING IN WATER. IN ADDITION, A LOSS OF ELEVATOR CONTROL WAS ENCOUNTERED DUE TO A STRESS CORROSION FAILURE OF AN ELEVATOR CONTROL CABLE TURNBUCKLE AS A RESULT OF INADEQUATE MAINTENANCE AND INSPECTION. FACTORS WHICH CONTRIBUTED TO THE ACCIDENT WERE: A PREVIOUS HARD LANDING AS A RESULT OF AN IMPROPER LEVEL-OFF, AND THE PILOT'S LACK OF RECENT EXPERIENCE IN THE MAKE AND MODEL AIRPLANE. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Hard landing, landing - flare/touchdown - level off - improper, pilot in command (contributing factor) - Airframe/component/system failure/malfunction, cruise - flt control syst,elevator control cable/rod - corroded (cause) - maintenance,inspection - inadequate, other maintenance personnel (cause) - flt control syst,elevator control cable/rod - stress corrosion (cause) - maintenance,annual inspection - not performed, pilot in command (cause) - Gear not retracted, landing - flare/touchdown - precautionary landing - performed, pilot in command - gear retraction - not selected, pilot in command (cause) - lack of recent experience, pilot in command (contributing factor) - wheels down landing in water - inadvertent, pilot in command (cause) - Nose over, landing - flare/touchdown ## Analysis DURING THE 18-MONTH PERIOD PRIOR TO THIS FLIGHT THE ACFT HAD BEEN REBUILT. THIS WAS THE FIRST FLIGHT TO LEAK-CHECK THE HULL BEFORE PAINTING. SEVERAL WATER LANDINGS WERE MADE; THE LAST BEING REFERRED TO BY A WITNESS 'IT HIT THE WATER'. THE PILOT STATED THAT WHILE RETURNING TO LONG BEACH ALL ELEVATOR CONTROL WAS LOST. HE ELECTED TO LAND BACK IN THE WATER, AND FORGOT THE WHEELS WERE DOWN. THE LANDING WAS MADE USING POWER AND ELEV TRIM, AND THE ACFT NOSED OVER NEAR THE SHORELINE. INVESTIGATION REVEALED A DISCOLORED & CORRODED ELEV CONTROL CABLE TURNBUCKLE THAT HAD FAILED DUE TO STRESS CORROSION CRACKING, WITH THE FINAL FAILURE MODE OF TENSILE OVERLOAD. THE PILOT STATED THAT HE HAD NOT MADE A WATER LANDING IN OVER ONE YEAR. ABOUT 2-1/2 HRS AFTER THE OCCURRENCE THE PILOT'S BLOOD ALCOHOL LEVEL WAS 0.022%. ## Aircraft - Registration: [N86640](https://openairdocs.org/deregistered/N86640-2013-09-17), registration cancelled 2013-09-17, S/N 1160, built 1942 (OpenAirDocs) - Reported make and model: GRUMMAN G21A - Registry model: [Grumman G-21A](https://openairdocs.org/model/grumman-g-21a) (registry code 3951204) (OpenAirDocs) - Registry engine: [Pratt & Whitney R-985 series](https://openairdocs.org/engine/pratt-whitney-r-985-series) (registry code 52008, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 1160 - Engines: P&W R-985 450 horsepower reciprocating - Damage: Substantial damage - Flight: Part 91 - Operator: Richard Probert - Airworthiness certificate: Standard, Normal ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 40; commercial; airplane ratings: single-engine land, multi-engine sea, multi-engine land; instrument ratings: airplane; medical: class 3, expired; toxicology performed; flight hours: 1,600 total, 300 in this make and model, 1,500 as pilot in command, 30 in the last 90 days, 5 in the last 30 days ## Weather - Conditions: Visual (VMC), Day - Wind: 250° at 5 knots - Visibility: 15 statute miles - Lowest ceiling: none - Temperature: 70 °F, dew point -0 °F ## 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 19900616021249A](https://openairdocs.org/incident/19900616021249A), Jun 16, 1990: Grumav G21A, Long Beach, CA, Substantial damage. Elevator turnbuckle failed from corrosion. No current airworthy inspection. Pilot not current in type. No medical. ## Other investigations on N86640 (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 MIA740KT73](https://openairdocs.org/ntsb/MIA740KT73), Apr 24, 1974: Grumman G-21A (N86640), Nassau, Burkina Faso, 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.