# NTSB DEN87FA153: Concept 70, N23405, Durango, CO, June 17, 1987

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Field investigation · Final report
- Date: June 17, 1987, 17:00 local (23:00 UTC)
- Place: Durango, CO
- Coordinates: 37.269832, -107.880004 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=37.2698&lon=-107.8800&mi=10
- Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed, report October 6, 1988
- Report: Approved by Office Director
- NTSB case key (mKey): 17113
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DEN87FA153
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/17113/pdf
- Page: https://openairdocs.org/ntsb/DEN87FA153

## Sequence of events

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

- Airframe/component/system failure/malfunction, maneuvering
  - aerobatics - attempted, pilot in command (cause)
  - overconfidence in aircraft's ability, pilot in command (cause)
  - design stress limits of aircraft - exceeded, pilot in command (cause)
  - wing,bracing strut - overload (contributing factor)
  - flight control,elevator attachment - overload (contributing factor)
  - performance data - disregarded, pilot in command (cause)
- In flight collision with terrain/water, descent - uncontrolled

## Analysis

THE PLT REPORTED THAT HE HAD BEEN FLYING FOR ONE HOUR AND HAD BEEN DOING ACROBATICS. HE HAD STARTED AN INSIDE LOOP AND DURING PULL UP, HE REPORTED INDICATING 5.5 G'S ON HIS NEW G METER. THE PLT REPORTED THAT BOTH WINGS LEFT THE ACFT AND HE JETTISONED THE CANOPY. HE BAILED OUT AND LANDED SAFELY IN TREES. THE ACFT FUSELAGE IMPACTED IN A FIELD AND WAS DESTROYED. THE WINGS AND OTHER WRECKAGE WERE SCATTERED OVER FARM LAND IN A ONE HALF MILE PATH.

## Aircraft

- Registration: [N23405](https://openairdocs.org/deregistered/N23405-2013-04-15), registration cancelled 2013-04-15, S/N 01, built 1975 (OpenAirDocs)
- Reported make and model: CONCEPT 70
- Registry model: [Concept Sailplanes CONCEPT-70](https://openairdocs.org/model/concept-sailplanes-concept-70) (registry code 0564770) (OpenAirDocs)
- Registry engine: [NONE](https://openairdocs.org/engine/none) (registry code 00000, none) (OpenAirDocs)
- Category: Glider, amateur-built
- Serial number: 01
- Airframe hours: 500
- Engines: NONE NONE unknown
- Damage: Substantial damage
- Flight: Personal, Part 91
- Operator: Donald E. Howard
- Registered owner: Coe A.D.
- Airworthiness certificate: Special, Experimental (Special)
- Last inspection: Annual, June 1, 1984
- Departed: 9C08, DURANGO, CO

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 39; private; seat: center; flight hours: 133 total, 133 in this make and model, 98 as pilot in command, 2 in the last 90 days, 2 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: calm
- Visibility: 50 statute miles
- Lowest ceiling: none
- Temperature: 64 °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 19870617072969A](https://openairdocs.org/incident/19870617072969A), Jun 17, 1987: Amtrbs CONCEPT70, Durango, CO, Destroyed. Inflight breakup during a loop. Exceeded the g load. Glider out of annual and non acrobatic. Pilot bailed out.

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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