# NTSB DEN90LA040: Boeing A75N1, N49733, Ft Collins, CO, January 12, 1990

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: January 12, 1990, 11:50 local (18:50 UTC)
- Place: Ft Collins, CO
- Coordinates: 40.550422, -105.059715 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=40.5504&lon=-105.0597&mi=10
- Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 2 uninjured
- Status: Completed, report June 28, 1991
- Report: Approved by Office Director
- NTSB case key (mKey): 17880
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DEN90LA040
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/17880/pdf
- Page: https://openairdocs.org/ntsb/DEN90LA040

## Probable cause

FAILURE OF THE PILOT TO MAINTAIN DIRECTIONAL CONTROL, WHICH RESULTED IN AN INADVERTENT GROUND SWERVE. A FACTOR RELATED TO THE ACCIDENT WAS:  THE PILOT'S LACK OF FAMILIARITY WITH THE AIRCRAFT.

## Sequence of events

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

- Loss of control - on ground/water, landing - roll
  - directional control - not maintained, pilot in command (cause)
  - ground loop/swerve - inadvertent, pilot in command (cause)
  - lack of familiarity with aircraft, pilot in command (contributing factor)
- Dragged wing,rotor,pod,float or tail/skid, landing - roll

## Analysis

THE NEW OWNER/PLT (PIC) TOOK OFF FROM DOWNTOWN FORT COLLINS AIRPARK TO PRACTICE LANDINGS WITH THE PREVIOUS OWNER ACTING AS A SAFETY PLT. AFTER PRACTICING A NUMBER OF LANDINGS, THEY LANDED AT FORT COLLINS-LOVELAND MUNI ARPT & REFUELED. THE PLTS THEN TOOK OFF TO RETURN TO THE DOWNTOWN ARPT FOR THE FINAL LANDING. WHILE LANDING IN CALM WIND, THE TAILWHEEL EQUIPPED ACFT VEERED TO THE LEFT & WENT OFF THE RWY. AS IT VEERED LEFT, THE RIGHT WING DRAGGED THE GROUND & WAS DAMAGED.

## Aircraft

- Registration: [N49733](https://openairdocs.org/aircraft/N49733), registered now, S/N 75-4276 (OpenAirDocs)
- Reported make and model: BOEING A75N1 (A75N-1)
- Registry model: [Boeing A75N1(PT17)](https://openairdocs.org/model/boeing-a75n1-pt17) (registry code 1380134) (OpenAirDocs)
- Registry engine: [Continental R670-SERIES series](https://openairdocs.org/engine/continental-r670-series-series) (registry code 17016, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: 75-4276
- Engines: CONTINENTAL W-670-6A 220 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Operator: Dennis Bruce Whitsell
- Registered owner: Unknown
- Airworthiness certificate: Standard, Utility
- Departed: FNL, FT COLLINS, CO
- Airport: 3V5, Ft Collins Downtown, runway 11, 4,700 × 48 ft, asphalt

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 32; flight instructor, commercial; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 2, valid medical--w/ waivers/lim; flight hours: 144 total, 4 in this make and model, 1,376 as pilot in command, 56 in the last 90 days, 22 in the last 30 days, 1 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: calm
- Visibility: 60 statute miles
- Lowest ceiling: none
- Temperature: 36 °F, dew point -0 °F
- Altimeter: 30.00 inHg

## 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 19900112001069A](https://openairdocs.org/incident/19900112001069A), Jan 12, 1990: Boeing A75N1, Fort Collins, CO, Substantial damage. New owner being checked out in tail dragger. Veered on landing. Check pilot also on controls resulted in ground loop

## Other investigations on N49733 (1)

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.

- [NTSB MIA69D0264](https://openairdocs.org/ntsb/MIA69D0264), Jul 25, 1968: Stearman PT-17 (N49733), Colquitt, GA, minor damage

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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