# NTSB NYC83FU009: American Aerolights Eagle XL, Mayville, NY, August 6, 1983

- Type: NTSB accident investigation
- Classification: Accident · Fatal · Final report
- Date: August 5, 1983, 20:30 local (Aug 6, 1983, 00:30 UTC)
- Place: Mayville, NY
- Coordinates: 42.250232, -79.499702 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=42.2502&lon=-79.4997&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: Fatal
- Injuries: 1 fatal
- Status: Completed
- Report: Approved by Office Director
- NTSB case key (mKey): 35132
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=NYC83FU009
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/35132/pdf
- Page: https://openairdocs.org/ntsb/NYC83FU009

## Sequence of events

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

- Airframe/component/system failure/malfunction, cruise - normal
  - reduction gear assy - other (cause)
  - maintenance,installation - improper, other maintenance personnel (cause)
  - acft/equip,inadequate design, production/design personnel (cause)
  - reduction gear assy - failure,total (cause)
  - reduction gear assy - disconnected (contributing factor)
  - propeller system/accessories - vibration (contributing factor)
  - wing - failure,partial (contributing factor)
- Loss of control - in flight, cruise
- In flight collision with terrain/water, descent - uncontrolled

## Analysis

ACCORDING TO WITNESSES, THE ULTRALIGHT WAS IN LEVEL FLT AT APRX 150 TO 200 FT AGL WHEN THEY HEARD A LOUD BANG. SHORTLY THEREAFTER, THE ENG NOISE CEASED & THE VEHICLE ENTERED A SPIRALING DESCENT & CRASHED. A RIP IN THE WING CENTER SECTION WAS SEEN PRIOR TO IMPACT. AN EXAM REVEALED THAT THE LARGE REDUCTION ASSEMBLY, DRIVE PULLEY HAD SEPARATED FROM THE DRIVE SHAFT. 2 OF 4 CONNECTING BOLTS WERE FOUND FRACTURED & THE OTHER 2 HAD SEPARATED WITHOUT FRACTURING. THERE WAS EVIDENCE OF LOOSENESS & FRETTING PRIOR TO THE BOLT FAILURES. RED PAINT HAD TRANSFERRED FROM THE PROP TIPS TO THE WING STRUTS. THEPROP TIPS HAD SEPARATED & THE WING FABRIC HAD TORN AT THE WING ROOTS ON EACH SIDE OF THE CENTER SECTION. THE FAILED & MISSING BOLTS HAD BEEN INSTALLED DURING A DRIVE SHAFT PULLEY ADAPTER HUB RETROFIT, APRX 3 FLT HRS PRIOR TO THE ACCIDENT,BEFORE THE PLT PURCHASED THE ULTRALIGHT FROM A PREVIOUS OWNER. NO WASHERS, TORQUE VALUES OR SAFETYING REQUIREMENTS WERE SPECIFIED FOR THE BOLTS IN THE RETROFIT INSTRUCTIONS & THE BOLTS HAD NOT BEEN SAFETY WIRED.

## Aircraft

- Registration: UNREG (not matched to a registry record)
- Reported make and model: AMERICAN AEROLIGHTS EAGLE XL
- Category: Ultralight, amateur-built
- Serial number: 20029
- Engines: CUYUNA 430R 30 horsepower reciprocating
- Damage: Destroyed
- Flight: Personal, Part 103
- Registered owner: William Phillips II
- Departed: D79, MAYVILLE, NY
- Airport: D79, Dart

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 41; airplane ratings: single-engine land; medical: unknown; seat: front; toxicology performed; flight hours: 10 total, 1 in this make and model, 1 as pilot in command, 1 in the last 90 days, 1 in the last 30 days, 1 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 40° at 4 knots
- Visibility: 3 statute miles
- Lowest ceiling: none
- Temperature: 77 °F, dew point 70 °F
- Altimeter: 30.00 inHg
- Observed at: BUF, 53 nm away

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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