# NTSB CHI82DA237: Waco UPF-7, N39714, Popular Grove, IL, July 4, 1982

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Final report
- Date: July 3, 1982, 20:00 local (Jul 4, 1982, 01:00 UTC)
- Place: Popular Grove, IL
- Coordinates: 42.360042, -88.819572 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=42.3600&lon=-88.8196&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 2 uninjured
- Status: Completed, report July 3, 1983
- Report: Approved by Office Director
- NTSB case key (mKey): 72283
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CHI82DA237
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/72283/pdf
- Page: https://openairdocs.org/ntsb/CHI82DA237

## Sequence of events

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

- Loss of engine power(total) - mech failure/malf, cruise - normal
  - propeller system/accessories,blade - separation (cause)
  - propeller system/accessories,blade - fatigue (cause)
  - propeller system/accessories,blade - overload (cause)
- Hard landing, landing - flare/touchdown

## Analysis

THE PILOT EXPERIENCED SEVERE ENGINE VIBRATION DURING CRUISE FLIGHT. THE PILOT PERFORMED AN EMERGENCY LANDING IN A FIELD. BECAUSE OF THE LENGTH OF THE FIELD THE PILOT LANDED HARD AND THE LEFT MAIN GEAR COLLAPSED. THE SEPARATED GEAR STRUCK AND FRACTURED THE LEFT WING SPAR. INVESTIGATION REVEALED THE ENGINE VIBRATION WAS INDUCED BY THE SEPARATION OF SIX INCHES OF THE BLADE TIP OF THE ALUMINUM CONSTRUCTED CURTIS-REED PROPELLER.

## Aircraft

- Registration: [N39714](https://openairdocs.org/aircraft/N39714), registered now, S/N 5847, built 1942 (OpenAirDocs)
- Reported make and model: WACO UPF-7
- Registry model: [Waco UPF-7](https://openairdocs.org/model/waco-upf-7) (registry code 9601302) (OpenAirDocs)
- Registry engine: [Continental W670 series](https://openairdocs.org/engine/continental-w670-series) (registry code 17018, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: 5847
- Airframe hours: 26518
- Engines: CONTINENTAL W-6706A 220 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Operator: William C. Thomas
- Registered owner: Richard Thomas
- Departed: BELVIDERE, IL
- Destination: BELVIDERE, IL

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 28; private; airplane ratings: single-engine sea, single-engine land; medical: class 3, valid medical--no waivers/lim.; flight hours: 774 total, 39 in this make and model, 703 as pilot in command, 52 in the last 90 days, 2 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 180° at 4 knots
- Visibility: 10 statute miles
- Lowest ceiling: 25,000 ft broken
- Temperature: 172 °F
- Altimeter: 29.00 inHg
- Observed at: RFD, 25 nm away

## 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 19820703028499A](https://openairdocs.org/incident/19820703028499A), Jul 3, 1982: Waco UPF7, Popular Grove, IL, Substantial damage. Crash occurred during emergency landing after six inches of one propeller blade broke off.

## Other investigations on N39714 (2)

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 CHI07LA005](https://openairdocs.org/ntsb/CHI07LA005), Oct 8, 2006: Waco UPF7 (N39714), Lake Village, IN, minor damage. Probable cause: Inadequate visual lookout by the pilot. A factor associated with the accident was that neither airplane was equipped with communications equipment.
- [NTSB NYC86LA008](https://openairdocs.org/ntsb/NYC86LA008), Oct 14, 1985: Waco UPF-7 (N39714), Norwood, MA, substantial 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.

---
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.