# NTSB BFO88FA067: de Havilland DHC-6-200, N7267, Chantilly, VA, July 20, 1988

- Type: NTSB accident investigation
- Classification: Accident · Fatal · Field investigation · Final report
- Date: July 20, 1988, 16:08 local (20:08 UTC)
- Place: Chantilly, VA
- Location: 38.9445° N, 77.4558° W: Placed by OpenAirDocs at Washington Dulles International Airport (IAD), within about a mile (OpenAirDocs)
- Nearby events: https://openairdocs.org/map.md?lat=38.9445&lon=-77.4558&mi=10
- Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping)
- Highest injury: Fatal
- Injuries: 1 fatal
- Status: Completed, report June 11, 1990
- Report: Approved by Office Director
- NTSB case key (mKey): 11372
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=BFO88FA067
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/11372/pdf
- Page: https://openairdocs.org/ntsb/BFO88FA067

## Probable cause

THE PILOT INADVERTENTLY MISUSED THE FLAPS, BY FAILING TO SET THE FLAPS TO THE PROPER SETTING. THE FLAPS WERE SET FULL DOWN. THIS CAUSED THE AIRCRAFT TO PITCH UP STEEPLY AFTER LIFTOFF. ADDITIONALLY, THE FLIGHT CONTROL LOCK WAS PROBABLY INSTALLED DURING SOME PORTION, IF NOT THE ENTIRE FLIGHT, WHICH PREVENTED FLIGHT CONTROL OPERATION. THE PILOT SUBSEQUENTLY FAILED TO MAINTAIN ADEQUATE FLYING SPEED AND THE AIRCRAFT STALLED. CONTRIBUTING FACTORS ARE THE PILOT'S INATTENTION AND HIS FAILURE TO ADEQUATELY USE THE CHECKLIST.

## Sequence of events

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

- Loss of control - in flight, takeoff - initial climb
  - raising of flaps - not performed, pilot in command (cause)
  - inattentive, pilot in command (contributing factor)
  - checklist - not used, pilot in command (contributing factor)
  - procedures/directives - not followed, pilot in command (contributing factor)
  - removal of control/gust lock(s) - inadvertent use, pilot in command (contributing factor)
- In flight collision with terrain/water, descent - uncontrolled

## Analysis

THIS WAS THE FIRST FLIGHT AFTER A MAINTENANCE INSPECTION. THE FLAPS WERE LEFT FULL DOWN AFTER A POST-INSPECTION BY COMPANY MECHANICS, BEFORE THE FLIGHT. WITNESSES STATED THE FLAPS WERE DOWN WHEN THE AIRCRAFT TAXIED TO TAKEOFF ON RWY 19L. WITNESSES STATED THE AIRCRAFT CLIMBED STEEPLY AFTER IT LIFTED OFF WITH A PITCH ATTITUDE UP TO 60 DEGREES. ACCORDING TO WITNESSES, THE AIRCRAFT CLIMBED TO 200 TO 500 FT AGL, BEFORE IT STALLED AND DESCENDED NOSE DOWN IN A LEFT TURN. THE AIRCRAFT CRASHED ABOUT 300 FT LEFT OF AND 2000 FT DOWN THE RWY. EXAMINATION OF THE AIRCRAFT REVEALED THE FLAPS WERE FULL DOWN. THE SCROLL TYPE CHECKLIST WAS POSITIONED AT THE BEGINNING OF THE TAKEOFF CHECK. THE FLIGHT MANUAL RECOMMENDS A 10 DEGREE FLAP SETTING FOR TAKEOFF AND PROHIBITS FLAP FULL DOWN TAKEOFF. REVIEW OF PREVIOUS DHC-6 ACCIDENTS INVOLVING FLAP FULL DOWN RESULTED IN A STEEP TAKEOFF CLIMB AND EXCESSIVE PITCH ATTITUDE FOLLOWED BY A STALL. THE POSITION OF THE CONTROL LOCK SUGGESTS IT MAY HAVE BEEN IN THE LOCKED POSITION DRG THE TKOF.

## Aircraft

- Registration: [N7267](https://openairdocs.org/deregistered/N7267-2013-07-23), registration cancelled 2013-07-23, S/N 195, built 1968 (OpenAirDocs)
- Reported make and model: de Havilland DHC-6-200
- Registry model: [Dehavilland DHC-6 TWIN OTTER](https://openairdocs.org/model/dehavilland-dhc-6-twin-otter) (registry code 2802606) (OpenAirDocs)
- Registry engine: [Pratt & Whitney Canada PT6A-60A](https://openairdocs.org/engine/pratt-whitney-canada-pt6a-60a) (registry code 52043, turbo-prop) (OpenAirDocs)
- Category: Airplane
- Serial number: 195
- Airframe hours: 10513
- Engines: P&W PT-6A-20A 579 horsepower turbo prop
- Damage: Destroyed
- Fire: On-Ground
- Flight: Ferry, Part 91
- Registered owner: Fairways Corp.
- Airworthiness certificate: Standard, Normal
- Last inspection: AAIP, July 19, 1988, 1 hours before
- Destination: DCA, WASHINGTON, DC
- Flight plan: IFR
- Airport: IAD, Dulles Int'L, runway 19L, 11,500 × 150 ft, concrete

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 50; commercial, airline transport; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane, helicopter; medical: class 1, valid medical--w/ waivers/lim; seat: left; toxicology performed; flight hours: 12,400 total, 120 in the last 90 days, 28 in the last 30 days

## Weather

- Conditions: Visual (VMC), Day
- Wind: 150° at 10 knots
- Visibility: 8 statute miles
- Lowest ceiling: 3,400 ft broken
- Temperature: 86 °F, dew point 75 °F
- Altimeter: 29.00 inHg
- Observed at: IAD

## 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 19880720027129A](https://openairdocs.org/incident/19880720027129A), Jul 20, 1988: Dhav DHC6200, Washington, DC, Destroyed, 1 fatal. Flaps left full down after inspection. Took off flaps down pitched up stalled. Nosed down. Control lock also on.

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.