# NTSB MIA91LA043: Piper PA-28-151, N4480F, Jupiter, FL, December 12, 1990

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: December 12, 1990, 16:57 local (21:57 UTC)
- Place: Jupiter, FL
- Coordinates: 26.919586, -80.099159 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=26.9196&lon=-80.0992&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 4 uninjured
- Status: Completed, report December 14, 1992
- Report: Approved by Office Director
- NTSB case key (mKey): 32803
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=MIA91LA043
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/32803/pdf
- Page: https://openairdocs.org/ntsb/MIA91LA043

## Probable cause

PARTIAL LOSS OF ENGINE POWER DUE TO FAILURE OF AN EXHAUST VALVE, DUE TO A VALVE GUIDE THAT WAS WORN BEYOND SPECIFICATIONS.

## Sequence of events

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

- Loss of engine power(partial) - mech failure/malf, cruise - normal
  - engine assembly,valve,exhaust - failure,total (cause)
- Forced landing, descent - emergency
- In flight collision with terrain/water, landing
  - terrain condition - water

## Analysis

DURING CRUISE FLT ABOUT 1/2 MILE OFFSHORE AT AN ALT OF 500 FT, THE PLT STATED THAT HE HEARD A KNOCKING SOUND & THE ENG LOST POWER. UNABLE TO MAINTAIN ALT, HE DITCHED THE ACFT. THE ACFT WAS RECOVERED & THE ENG WAS REMOVED FOR FURTHER EXAM. EXAM OF THE ENG REVEALED THAT THE NO.2 CYL EXHAUST VALVE FAILED DUE TO A WORN VALVE GUIDE. THE INTERNAL DIAMETER OF THE VALVE GUIDE AT THE TOP MEASURED .539' & THE BOTTOM MEASURE .563'. FACTORY SPECIFICATIONS ARE .4985' TO .4995'. THE ENG LOGBOOKS WERE INSIDE THE ACFT & WERE NOT RECOVERED.

## Aircraft

- Registration: [N4480F](https://openairdocs.org/deregistered/N4480F-1996-09-13), registration cancelled 1996-09-13, S/N 287715036 (OpenAirDocs)
- Reported make and model: PIPER PA-28-151
- Registry model: [Piper PA-28-151](https://openairdocs.org/model/piper-pa-28-151) (registry code 7102805) (OpenAirDocs)
- Category: Airplane
- Serial number: 28-7715036
- Airframe hours: 5740
- Engines: LYCOMING O-320-E3D 150 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Operator: Zimmerman, Barry L.
- Registered owner: Zimmerman, B. L. & Patricia L
- Departed: FXE, FORT LAUDERDALE, FL
- Destination: SUA, STUART, FL

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 27; flight instructor, commercial; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 2, valid medical--no waivers/lim.; seat: right; flight hours: 1,510 total, 200 in this make and model, 1,200 as pilot in command, 200 in the last 90 days, 50 in the last 30 days, 5 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 120° at 9 knots
- Visibility: 10 statute miles
- Lowest ceiling: 30,000 ft broken
- Temperature: -0 °F, dew point -0 °F
- Altimeter: 30.00 inHg
- Observed at: PBI, 31 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 19901212053899A](https://openairdocs.org/incident/19901212053899A), Dec 12, 1990: Piper PA28151, Jupiter, FL, Substantial damage. Engine knock and power loss flying low offshore. Ditched in ocean. NR2 cylinder exhaust valve failed. Worn guide.

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.