# NTSB DEN91LA091: Boeing E75N1, N45747, Vail, CO, June 26, 1991

- Type: NTSB accident investigation
- Classification: Accident · Minor injuries · Limited investigation · Final report
- Date: June 26, 1991, 17:50 local (23:50 UTC)
- Place: Vail, CO
- Location: 39.6378° N, 106.3625° W: Placed by OpenAirDocs: center of Vail, CO, within about 6 miles (OpenAirDocs)
- Nearby events: https://openairdocs.org/map.md?lat=39.6378&lon=-106.3625&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: Minor injuries
- Injuries: 2 minor
- Status: Completed, report May 5, 1993
- Report: Approved by Office Director
- NTSB case key (mKey): 18105
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DEN91LA091
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/18105/pdf
- Page: https://openairdocs.org/ntsb/DEN91LA091

## Probable cause

A SEVERE DOWNDRAFT.  A FACTOR WAS:  THE PILOT'S FAILURE TO OBTAIN A WEATHER BRIEFING.

## Sequence of events

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

- In flight encounter with weather, cruise - normal
  - preflight briefing service - not obtained, pilot in command (contributing factor)
  - weather condition - downdraft (cause)
- Loss of control - in flight, descent - uncontrolled
  - aircraft control - not maintained, pilot in command
- In flight collision with terrain/water, landing - flare/touchdown
  - airport facilities,runway/landing area condition - roadway/highway
- Nose over, other

## Analysis

THE FLIGHT WAS THE BEGINNING OF A 2 MONTH AROUND THE WORLD GOODWILL FLIGHT IN AN OPEN COCKPIT BIPLANE.  COMMEMORATING THE SAME FEAT ACCOMPLISHED BY TWO RUSSIAN PILOTS IN 1937.  ABOARD THE AIRPLANE WAS THE 1982 SOVIET AEROBATIC CHAMPION AND CURRENT COACH OF THE SOVIET AEROBATIC TEAM.  THE AIRPLANE WAS FLYING BELOW THE RIDGE LINE, APPROACHING VAIL PASS (ELEVATION 10,603 FT MSL) ON THE NORTH SIDE OF I 70 AT 9200 FEET.  THE PILOT SAID THEY ENCOUNTERED A SEVERE DOWNDRAFT, DRIVING THE AIRPLANE INTO THE GROUND. A REVIEW OF WEATHER DATA SHOWED EIGHT PIREPS FILED FOR MODERATE TO SEVERE TURBULENCE OVER THE COLORADO MOUNTAINS.

## Aircraft

- Registration: [N45747](https://openairdocs.org/aircraft/N45747), registered now, S/N 75-5459, built 1943 (OpenAirDocs)
- Reported make and model: BOEING E75N1
- Registry model: [Boeing E75](https://openairdocs.org/model/boeing-e75) (registry code 1380120) (OpenAirDocs)
- Registry engine: [Lycoming R680](https://openairdocs.org/engine/lycoming-r680) (registry code 41540, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: 75-5459
- Engines: LYCOMING R-680-8 225 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Operator: Hays, Carl W.
- Registered owner: Hays, Carl W.
- Departed: 0C05, MACK, CO
- Destination: 1V5, BOULDER, CO

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 48; private; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 3, valid medical--w/ waivers/lim; seat: rear; flight hours: 1,450 total, 349 in this make and model, 1,349 as pilot in command, 38 in the last 90 days, 15 in the last 30 days, 2 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 250° at 14 knots
- Visibility: 40 statute miles
- Lowest ceiling: 10,000 ft broken
- Temperature: -0 °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 19910626024019A](https://openairdocs.org/incident/19910626024019A), Jun 26, 1991: Boeing E75, Vail, CO, Substantial damage. Encountered unrecoverable downdraft flying below mountain ridge. Made hard landing and flipped inverted.

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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