# NTSB MIA87LA266: Aero Commander 720, N4100S, 50 Nw San Juan, PR, September 30, 1987

- Type: NTSB accident investigation
- Classification: Accident · Serious injuries · Limited investigation · Final report
- Date: September 30, 1987, 08:51 local (12:51 UTC)
- Place: 50 Nw San Juan, PR
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: Serious injuries
- Injuries: 1 serious, 1 minor
- Status: Completed, report May 16, 1989
- Report: Approved by Office Director
- NTSB case key (mKey): 31974
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=MIA87LA266
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/31974/pdf
- Page: https://openairdocs.org/ntsb/MIA87LA266

## Sequence of events

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

- Loss of engine power, cruise - normal
  - 1 engine
  - reason for occurrence undetermined (cause)
- Forced landing, descent - emergency
- Ditching, landing - flare/touchdown

## Analysis

FIFTEEN MINUTES AFTER A NORTHWEST DEPARTURE FROM SAN JUAN INTERNATIONAL ARPT THE PLT REPORTED THAT THE FLT WAS RETURNING TO LAND AFTER SECURING THE RT ENG DUE TO REPORTED PROBLEMS. UNABLE TO MAINTAIN ALTITUDE THE ACFT WAS DITCHED APRX 50 MILES NORTHWEST OF THE ARPT. DENSITY ALTITUDE WAS COMPUTED TO BE 1900 FT AT THE ARPT 1 MINUTE AFTER THE DITCHING. ACCORDING TO THE ACFT OPERATING MANUAL, AT THE DESIGNED GROSS WEIGHT WITH A PROPERLY SECURED ENGINE AT THE ABOVE COMPUTED DENSITY ALTITUDE, THE SINGLE ENGINE RATE OF CLIMB WOULD BE 212 FEET PER MINUTE. THE ACFT & LOGBOOKS HAVE NOT BEEN RECOVERED THEREFORE THE CAUSE OF THE REPORTED ENG FAILURE & MAINTENANCE INFORMATION COULD NOT BE DETERMINED & OBTAINED RESPECTIVELY.

## Aircraft

- Registration: [N4100S](https://openairdocs.org/deregistered/N4100S-2012-11-19), registration cancelled 2012-11-19, S/N 720-660-7, built 1960 (OpenAirDocs)
- Reported make and model: AERO COMMANDER 720
- Registry model: [Aero Commander 720](https://openairdocs.org/model/aero-commander-720) (registry code 0141802) (OpenAirDocs)
- Registry engine: [Lycoming GSO&IGSO-480 series](https://openairdocs.org/engine/lycoming-gso-igso-480-series) (registry code 41529, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: 720-660-7
- Engines: LYCOMING GSO-480-B1A6 340 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Registered owner: Carlo Claro
- Airworthiness certificate: Standard, Normal
- Departed: 5IG, SAN JUAN, PR
- Destination: FLL, FT. LAUDERDALE, FL
- Flight plan: VFR

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 56; commercial; airplane ratings: multi-engine land, single-engine land, multi-engine sea, single-engine sea; instrument ratings: airplane; medical: class 2, valid medical--w/ waivers/lim; seat: left; flight hours: 4,080 total, 43 in this make and model, 24 in the last 90 days, 1 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 130° at 9 knots
- Visibility: 15 statute miles
- Lowest ceiling: none
- Temperature: 88 °F, dew point 75 °F
- Altimeter: 29.00 inHg
- Observed at: SJU, 50 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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