# NTSB LAX89DUM01: Arlington Sisu 1A, N252JB, Borrego Springs, CA, October 15, 1988

- Type: NTSB accident investigation
- Classification: Accident · Fatal · Final report
- Date: October 15, 1988, 13:30 local (20:30 UTC)
- Place: Borrego Springs, CA
- Coordinates: 33.170047, -116.270523 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=33.1700&lon=-116.2705&mi=10
- Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping)
- Highest injury: Fatal
- Injuries: 1 fatal
- Status: Completed, report December 29, 1989
- Report: Approved by Office Director
- NTSB case key (mKey): 26138
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX89DUM01
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/26138/pdf
- Page: https://openairdocs.org/ntsb/LAX89DUM01

## Sequence of events

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

- Loss of control - in flight, maneuvering
  - airspeed(vs) - not maintained, pilot in command (cause)
  - stall/spin - inadvertent, pilot in command (cause)
- In flight collision with terrain/water, descent - uncontrolled

## Analysis

WHILE THERMAL SOARING, THE ACFT ENTERED A STEEP SPINNING DESCENT, THREE TURNS TO THE RIGHT FOLLOWED BY TWO TURNS TO THE LEFT AND GROUND IMPACT IN A NEAR VERTICAL ATTITUDE. NO EVIDENCE WAS FOUND OF AIRCRAFT STRUCTURAL FAILURE OR CONTROL MALFUNCTION. THE PILOT'S PARTNER IN OWNERSHIP OF THE GLIDER AND LONG-TIME CLOSE FRIEND STATED THAT HE HAD INADVERTENTLY ENTERED A SPIN IN THE AIRCRAFT SEVERAL YEARS EARLIER. HE INDICATED THAT HE HAD TROUBLE RECOVERING FROM IT, SPEED BRAKES WERE INEFFECTIVE AND HE COULD NOT RECOVER FROM IT UNTIL FLAPS WERE RETRACTED AND THE CONTROL STICK WAS PUSHED FULL FORWARD. ALTHOUGH THE WRECKAGE WAS FOUND WITH THE SPEED BRAKES RETRACTED AND FLAPS EXTENDED ABOUT 10 DEGREES, BOTH SYSTEMS DISPLAYED SUBSTANTIAL DAMAGE AND IT COULD NOT BE DETERMINED WHAT THEIR PRE-IMPACT POSITIONS WERE.

## Aircraft

- Registration: [N252JB](https://openairdocs.org/deregistered/N252JB-1988-12-06), registration cancelled 1988-12-06, S/N 105 (OpenAirDocs)
- Reported make and model: ARLINGTON SISU 1A
- Registry model: [Arlington SISU 1A](https://openairdocs.org/model/arlington-sisu-1a) (registry code 0780132) (OpenAirDocs)
- Category: Glider
- Serial number: 105
- Airframe hours: 1628
- Engines: unknown
- Damage: Substantial damage
- Flight: Personal, Part 91
- Operator: Beran, Lynda G.
- Registered owner: Beran, Lynda G
- Airworthiness certificate: Special, Experimental (Special)
- Last inspection: Unknown, April 1, 1988, 34 hours before
- Departed: L08, BORREGO SPRING, CA

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 40; private; airplane ratings: single-engine land; medical: class 3, valid medical--w/ waivers/lim; toxicology performed; flight hours: 1,011 total, 229 in this make and model, 3 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 120° at 6 knots
- Visibility: 35 statute miles
- Lowest ceiling: none
- Temperature: 90 °F, dew point 54 °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 19881015047629A](https://openairdocs.org/incident/19881015047629A), Oct 15, 1988: Amtr SISU1A, Borrego Springs, CA, Substantial damage, 1 fatal. Apparently stalled and went into a spin while soaring in a thermal. Pilot had no spin training. Failed to recover.

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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