# NTSB SEA86MA018: Gates Learjet 24D, N456JA, Juneau, AK, October 23, 1985

- Type: NTSB accident investigation
- Classification: Accident · Fatal · Major investigation · Final report
- Date: October 22, 1985, 20:43 local (Oct 23, 1985, 04:43 UTC)
- Place: Juneau, AK
- Location: 58.2960° N, 135.3421° W: Placed by OpenAirDocs from NTSB’s distance and direction from JUNEAU INTL (JNU), within about 8 miles (OpenAirDocs)
- Nearby events: https://openairdocs.org/map.md?lat=58.2960&lon=-135.3421&mi=10
- Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping)
- Highest injury: Fatal
- Injuries: 4 fatal
- Status: Completed
- Report: Approved by Office Director
- NTSB case key (mKey): 40507
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA86MA018
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/40507/pdf
- Page: https://openairdocs.org/ntsb/SEA86MA018

## Analysis

DRG ARRIVAL TO PICK UP A MED-EVAC PATIENT, THE FLT WAS CLRD FOR AN LDA-1 RWY 8 APCH VIA THE ASORT TRANSITION. THUS, THE PLT SHOULD HAVE CONTD SE ON J-541 TWD THE SSR VORTAC & INTERCEPTED THE LOCALIZER (LOC) AT ASORT; THEN TRACK INBND ON THELOC (062 DEG), USING I-JDL FREQ 109.9 MHZ (FREQ FOR LOC & CO-LOCATED DME). AFTER ASORT, MIN ALT WAS 6500' TO DIBOL INTX,5100' TO LYNNS INTXN & 3400' TO THE FAF AT BARLO INTXN. DME FM I-JDL TO THE INTXNS WAS: 18.2, 13.5 & 8 MI. DME FM SSR (SOUTH OF LOC TRACK) TO THE INTXNS WAS 11.2, 12.7 & APRX 16 MI. FLT RPRTD ASORT INBND WHILE DSCNDG THRU APRX 9500'. LASTRDO CALL WAS 30 SEC LATER WHILE DSCNDG THRU 8200', 14 MI WEST OF DIBOL. APRX 4 MI WEST OF DIBOL, ACFT IMPACTED MTN SIDE AT 3500' MSL. NO PREIMPACT MECH MALFUNCTION WAS FND. THERE WAS EVIDENCE THAT BOTH NAV'S WERE TUNED TO 109.9 MHZ, BUT DME CTL HEAD WAS INADVERTENTLY LEFT IN 'HOLD' PSN (LOCKING DME TO SSR RATHER THAN I-JDL) & CREW BEGAN A PREMATURE DSCNT.JUNEAU WX WAS IN PART: 600' SCATTERED, 3000' OVERCAST, 7 MI VISIBILITY. PIC WAS CURRENTLY FLYING BOTH LEARJET & DHC-7.

## Sequence of events

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

- In flight collision with terrain/water, approach - iaf to faf/outer marker (ifr)
  - comm/nav equipment,distance measuring eqpt(dme) - not switched (contributing factor)
  - flight/navigation instrument(s) - improper use of (cause)
  - habit interference, pilot in command (contributing factor)
  - became lost/disoriented - inadvertent, pilot in command (cause)
  - descent - premature (cause)
  - unsafe/hazardous condition - not identified, copilot/second pilot (cause)
  - light condition - dark night (contributing factor)
  - weather condition - clouds (contributing factor)
  - terrain condition - mountainous/hilly (contributing factor)
  - proper altitude - not maintained, pilot in command (cause)
  - terrain condition - rising (contributing factor)

## Aircraft

- Registration: N456JA (not matched to a registry record)
- Reported make and model: GATES LEARJET 24D
- Category: Airplane
- Serial number: 265
- Airframe hours: 6303
- Engines: GE CJ-610-6 2950 lbs thrust turbo jet
- Damage: Destroyed
- Flight: Part 135
- Registered owner: Era Helicopters, Inc
- Airworthiness certificate: Standard, Transport
- Last inspection: AAIP, September 19, 1985, 82 hours before
- Departed: ANC, ANCHORAGE, AK
- Destination: JNU, JUNEAU, AK
- Flight plan: IFR
- Airport: JNU, Juneau Intl, runway 8, 8,456 × 150 ft, asphalt

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 27; flight instructor, airline transport; airplane ratings: multi-engine land, single-engine sea, single-engine land; instrument ratings: airplane; medical: class 1, valid medical--no waivers/lim.; seat: left; toxicology performed; flight hours: 5,578 total, 547 in this make and model, 3,680 as pilot in command, 231 in the last 90 days, 47 in the last 30 days, 1 in the last 24 hours

## Weather

- Conditions: Night/dark
- Wind: calm
- Visibility: 7 statute miles
- Temperature: 34 °F, dew point 34 °F
- Altimeter: 29.00 inHg
- Observed at: JNU, 24 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 19851022076929A](https://openairdocs.org/incident/19851022076929A), Oct 22, 1985: Lear 24D, Juneau, AK, Destroyed, 2 fatal. Relying solely on the incorrectly tuned DME for distance resulted in an early descent and impact with mountainside.

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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