# NTSB DEN91LA053: Rockwell 112B, N1241J, Nederland, CO, March 18, 1991

- Type: NTSB accident investigation
- Classification: Accident · Serious injuries · Limited investigation · Final report
- Date: March 18, 1991, 13:00 local (20:00 UTC)
- Place: Nederland, CO
- Coordinates: 39.959167, -105.499938 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=39.9592&lon=-105.4999&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: Serious injuries
- Injuries: 2 serious
- Status: Completed, report May 3, 1993
- Report: Approved by Office Director
- NTSB case key (mKey): 18076
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DEN91LA053
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/18076/pdf
- Page: https://openairdocs.org/ntsb/DEN91LA053

## Probable cause

DETERIORATED IGNITION HARNESS AND IGNITION LEAD ARCING. FACTORS WERE THE HIGH DENSITY ALTITUDE AND 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(partial) - mech failure/malf, climb
  - weather condition - high density altitude (contributing factor)
  - ignition system,ignition harness - deteriorated (cause)
  - ignition system,ignition lead - arcing (cause)
- Forced landing, descent - emergency
- In flight collision with terrain/water, landing - flare/touchdown
  - terrain condition - none suitable (contributing factor)
  - terrain condition - mountainous/hilly
  - terrain condition - snow covered

## Analysis

AS THE AIRPLANE ENTERED A MOUNTAIN PASS, THE PILOT NOTICED DECREASING ENGINE MANIFOLD PRESSURE. UNABLE TO CLEAR HIGHER TERRAIN, HE MADE A FORCED LANDING IN DEEP SNOW. POST-ACCIDENT EXAMINATION REVEALED THE RIGHT IGNITION HARNESS WAS DETERIORATED AND THE IGNITION LEADS HAD ARCED. THE LEFT IGNITION HARNESS (SLICK 1200 SERIES) HAD BEEN ALTERED WITH THE USE OF UNAPPROVED BENDIX 'PANCAKE' GROMMETS. THE AIRPLANE HAD FLOWN 129 HRS SINCE THE LAST ANNUAL INSPECTION. CONDITIONS PREVENTED RECOVERY OF THE WRECKAGE UNTIL 6/27/91. TOTAL TIME ON THE ENGINE WAS 1,714 HRS. RECOMMENDED OVERHAUL INTERVAL WAS 1,800 HRS.

## Aircraft

- Registration: [N1241J](https://openairdocs.org/deregistered/N1241J-1992-10-23), registration cancelled 1992-10-23, S/N 504 (OpenAirDocs)
- Reported make and model: Rockwell 112B
- Registry model: [Rockwell International 112B](https://openairdocs.org/model/rockwell-international-112b) (registry code 7630303) (OpenAirDocs)
- Category: Airplane
- Serial number: 504
- Engines: LYCOMING IO-360-C1D6 200 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Operator: Berger, Henry M. & June H.
- Registered owner: Berger, Henry M. & June H.
- Departed: BJC, BROOMFIELD, CO
- Destination: SBS, STEAMBOAT SPRIN, CO
- Flight plan: VFR

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 68; commercial; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 3, valid medical--w/ waivers/lim; flight hours: 7,241 total, 317 in this make and model, 7,129 as pilot in command, 31 in the last 90 days, 17 in the last 30 days, 4 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: calm
- Visibility: 30 statute miles
- Lowest ceiling: none
- Temperature: -0 °F, dew point -0 °F
- Observed at: SBS, 65 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 19910318005659A](https://openairdocs.org/incident/19910318005659A), Mar 18, 1991: Gulstm 112B, Nederland, CO, Substantial damage. Rough mag and downdraft near mountain pass. Turned back. Unable clear terrain.

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.