# NTSB DEN85FTE01: Ultralight Flight Phantom II, Erie, CO, April 13, 1985

- Type: NTSB accident investigation
- Classification: Accident · Fatal · Final report
- Date: April 13, 1985, 11:03 local (18:03 UTC)
- Place: Erie, CO
- Coordinates: 40.020984, -105.040458 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=40.0210&lon=-105.0405&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: Fatal
- Injuries: 2 fatal
- Status: Completed
- Report: Approved by Office Director
- NTSB case key (mKey): 16563
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DEN85FTE01
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/16563/pdf
- Page: https://openairdocs.org/ntsb/DEN85FTE01

## Sequence of events

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

- Airframe/component/system failure/malfunction, descent
  - wing,bracing wire - fatigue (cause)
  - maintenance,installation - improper, pilot in command (cause)
  - wing - buckled
- In flight collision with terrain/water, descent - uncontrolled

## Analysis

THE ULTRALIGHT DESCENDED UNCONTROLLED TO GROUND IMPACT FOLLOWING A FAILURE OF THE OUTBOARD FORWARD WING SUPPORT CABLE/SWAGE. WITNESSES REPORTED THE ULTRALIGHT TURNED FROM NORTH TO SOUTH AND UPON LEVELING OUT, THE LEFT WING SNAPPED UPWARD, THE RIGHT WING COLLAPSED AND THE ULTRALIGHT ENTERED A DIVING TURN TO THE GROUND. POST ACCIDENT TESTS DISCLOSED ALL 4 CABLE ASS'Y WERE MANUFACTURED WITH THE NICROPRESS OVAL M SLEEVE BUT WERE SWAGED WITH THE WRONG SWAGING TOOL (SLIGHTLY LARGER) FOR THE OVAL P. THE CABLE SHOWED EVIDENCE OF FAILURE AT THE NICROPRESS SWAGED CONNECTIONS. TENSILE TESTS REVEALED THE IMPROPERLY SWAGED CONNECTIONS FAILED PREMATURELY DUE TO SLIPPAGE AT THE CONNECTIONS.

## Aircraft

- Registration: UNREG (not matched to a registry record)
- Reported make and model: ULTRALIGHT FLIGHT PHANTOM II
- Category: Ultralight, amateur-built
- Serial number: 2008
- Airframe hours: 12
- Engines: ROTAX 503 2-CYCLE 46 horsepower reciprocating
- Damage: Destroyed
- Flight: Instructional, Part 91
- Registered owner: Leonard Marnewecke
- Airworthiness certificate: Special, Experimental (Special); Special, Restricted (Special)
- Departed: 48V, ERIE AIRPARK, CO

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 42; private; airplane ratings: single-engine land; medical: class 3, valid medical--no waivers/lim.; seat: left

## Weather

- Conditions: Visual (VMC), Not reported
- Wind: 130° at 6 knots
- Visibility: 75 statute miles
- Lowest ceiling: none
- Temperature: 55 °F, dew point 28 °F
- Altimeter: 30.00 inHg

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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