# NTSB LAX88FA215: Cessna 421C, N98683, Shaver Lake, CA, May 29, 1988

- Type: NTSB accident investigation
- Classification: Accident · Fatal · Field investigation · Final report
- Date: May 28, 1988, 19:10 local (May 29, 1988, 02:10 UTC)
- Place: Shaver Lake, CA
- Coordinates: 37.130432, -119.220542 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=37.1304&lon=-119.2205&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: Fatal
- Injuries: 4 fatal
- Status: Completed, report July 9, 1990
- Report: Approved by Office Director
- NTSB case key (mKey): 25838
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX88FA215
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/25838/pdf
- Page: https://openairdocs.org/ntsb/LAX88FA215

## Probable cause

INFLIGHT ENCOUNTER WITH FORCASTED SEVERE ICING AND TURBULENCE BEYOND THE CAPABILITY OF EITHER THE AIRCRAFT OR THE PILOT , WHICH LED TO AN INFLGIHT LOSS OF CONTROL. FACTORS IN THE ACCIDENT WERE THE PILOTS LACK OF UNDERSTANDING OF HIGH ALTITUDE FLIGHT ASPECTS AND METEROLOGICAL PHENOMENA.

## Sequence of events

In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf).

- In flight encounter with weather, cruise - normal
  - weather condition - icing conditions (contributing factor)
  - weather condition - mountain wave (contributing factor)
  - weather condition - turbulence (contributing factor)
  - preflight briefing service - issued, nws personnel
  - lack of total experience in type operation, pilot in command (contributing factor)
  - weather evaluation - not understood, pilot in command (cause)
  - flight into known adverse weather - attempted, pilot in command (cause)
  - in-flight planning/decision - poor, pilot in command (contributing factor)
- Loss of control - in flight, cruise - normal
  - aircraft performance - exceeded (cause)
  - aircraft control - inadequate, pilot in command (cause)
  - stall/spin - inadvertent, pilot in command (cause)
- In flight collision with terrain/water, descent - uncontrolled

## Analysis

THE PLT BOUGHT THE ACFT ABOUT 1 MONTH PRIOR TO THE ACCIDENT. HE HAD LIMITED EXP IN THE ACFT, AND LIMITED EXP WITH HIGH ALT FLT AND ITS WX PHENOMONA. THE PLT OBTAINED TWO WX BREIFINGS FOR THE FLT. DURING BOTH, HE WAS ADVISED OF THE FORECAST AND PLT REPORTED CONDITIONS OF MODERATE TO SEVERE MIXED ICING AND TURBULENCE ASSOCIATED WITH A MTN WAVE ON THE EASTERN SIDE OF THE SIERRA NEVADA MTNS. INSTEAD OF FLYING ALONG HIS INTENDED ROUTE ON THE WESTERN SIDE OF THE MTNS, HE CHOSE A DIRECT ROUTE, WHICH PLACED THE ACFT ON THE EASTERN SIDE OF THE MTNS. THE TRACK OF THE ACFT WAS ESTABLISHED BY RECORDED RADAR DATA. THE DATA SHOWED THE ACFT IN CRUISE AT 16,500 FT UNTIL ABOUT 1 MIN PRIOR TO THE ACCIDENT. THE ACFT WAS SHOWN TO CLIMB TO 17,200 FEET BEFORE IT DISAPPEARED. THE LAST RADAR TARGET WAS OBSERVED ABOUT 2 MILES FROM THE IMPACT LOCATION. THE ACFT IMPACTED IN A STEEP NOSE DOWN DESCENT.

## Aircraft

- Registration: [N98683](https://openairdocs.org/deregistered/N98683-2017-02-17), registration cancelled 2017-02-17, S/N 421C0209, built 1976 (OpenAirDocs)
- Reported make and model: CESSNA 421C
- Registry model: [Cessna 421C](https://openairdocs.org/model/cessna-421c) (registry code 2076016) (OpenAirDocs)
- Registry engine: [Continental TSIO-360 series](https://openairdocs.org/engine/continental-tsio-360-series) (registry code 17019, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: 421C0209
- Airframe hours: 2575
- Engines: CONTINENTAL GTSI0-520L 375 horsepower reciprocating
- Damage: Destroyed
- Fire: On-Ground
- Flight: Personal, Part 91
- Operator: John D. Mac Donald
- Registered owner: Brooks Products, Inc.
- Airworthiness certificate: Standard, Normal
- Last inspection: Annual, September 21, 1987, 35 hours before
- Departed: L67, RIALTO, CA
- Destination: TRK, TRUCKEE, CA

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 47; private; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 3, valid medical--w/ waivers/lim; seat: left; flight hours: 3,060 total, 15 in this make and model, 2,950 as pilot in command, 25 in the last 90 days, 15 in the last 30 days, 1 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Dusk
- Wind: 200° at 35 knots, gusting 45
- Visibility: 50 statute miles
- Lowest ceiling: none
- Temperature: 61 °F
- Altimeter: 29.00 inHg
- Observed at: MMH, 15 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 19880528023329A](https://openairdocs.org/incident/19880528023329A), May 28, 1988: Cessna 421C, Shaver Lake, CA, Destroyed, 4 fatal. Lost control in area of mountain wave,severe turbulence and icing. Crashed out of control. Weather notamed for area.

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.

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