# NTSB CHI91LA299: Piper PA-23-250, N915PM, Boscobel, WI, September 20, 1991

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: September 20, 1991, 16:23 local (21:23 UTC)
- Place: Boscobel, WI
- Coordinates: 43.130714, -90.700698 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=43.1307&lon=-90.7007&mi=10
- Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 2 uninjured
- Status: Completed, report May 3, 1993
- Report: Approved by Office Director
- NTSB case key (mKey): 15190
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CHI91LA299
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/15190/pdf
- Page: https://openairdocs.org/ntsb/CHI91LA299

## Probable cause

IMPROPER REMEDIAL ACTION BY THE PILOT-IN-COMMAND (PIC), AND INADEQUATE MONITORING BY THE DESIGNATED PILOT EXAMINER (DPE) DURING A SIMULATED EMERGENCY PROCEDURE.  FACTORS RELATED TO THE ACCIDENT WERE: THE LOSS OF POWER IN ONE ENGINE DUE TO AN UNDETERMINED REASON, AND OBSTRUCTIONS IN THE EMERGENCY LANDING AREA THAT REQUIRED A DELAY OF GEAR EXTENSION IN ORDER TO REACH A CLEAR AREA.

## Sequence of events

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

- Miscellaneous/other, go-around (vfr)
  - go-around - performed, pilot in command
  - raising of flaps - not performed, pilot in command
  - emergency procedure - simulated, designated examiner
- Loss of engine power, climb
  - 1 engine
  - reason for occurrence undetermined (contributing factor)
- Forced landing, maneuvering - turn to landing area (emergency)
  - aircraft performance,engine out capability - exceeded
  - remedial action - improper, pilot in command (cause)
  - monitoring - inadequate, designated examiner (cause)
- Nose gear collapsed, landing - roll
  - terrain condition - high obstruction(s) (contributing factor)
  - gear extension - delayed

## Analysis

PURPOSE OF THE FLT WAS FOR THE PIC TO GET A MULTI-ENG (ADD-ON) RATING. DRG A 2 ENG GO-ARND, THE DESIGNATED PLT EXAMINER (DPE) SIMULATED AN ENG FAILURE BY RETARDING THE L THROTTLE. SOON THEREAFTER, THE AIRSPEED DECREASED & THE PIC ADZD THE DPE THAT HE WAS UNABLE TO MAINT ALT OR ATTITUDE. THE L THROTTLE WAS RE-ADVANCED WITH NO APPARENT EFFECT. THE PIC WAS UNABLE TO RESTORE PWR IN THE L ENG & RELINQUISHED THE FLT CTLS TO THE DPE. THE ACFT WAS PREPARED FOR AN APCH TO THE ARPT. WITH THE L ENG (& HYD SYS) INOP, THE PIC USED THE MANUAL HAND PUMP TO OPER THE GEAR & FLAPS (AFTER ASSURING THE ACFT WOULD CLR OBSTACLES). HE CONTD PUMPING, BUT THE ACFT WAS FORCED TO LND SHORT OF THE RWY & THE NOSE GEAR COLLAPSED DRG TCHDWN BFR IT WAS FULLY EXTDD. THE WING FLAPS WERE FND EXTDD. THE LNDG GEAR & WING FLAPS OPERD FM THE SAME HYD SYS; EITHER COULD HAVE BEEN ACTUATED INDEPENDENTLY OF THE OTR. THE HYD SYS WAS BUILT SO THAT WHEN THE GEAR & FLAPS WERE ENGAGED AT THE SAME TIME, THE GEAR WOULD COMPLETE ITS OPN BFR THE FLAPS OPERD. NO REASON FND FOR LOSS OF PWR IN L ENG.

## Aircraft

- Registration: [N915PM](https://openairdocs.org/deregistered/N915PM-2015-06-29), registration cancelled 2015-06-29, S/N 27-7305030, built 1973 (OpenAirDocs)
- Reported make and model: PIPER PA-23-250
- Registry model: [Piper PA-23-250](https://openairdocs.org/model/piper-pa-23-250) (registry code 7102308) (OpenAirDocs)
- Registry engine: [Lycoming TI0-540 series](https://openairdocs.org/engine/lycoming-ti0-540-series) (registry code 41533, turbo-prop) (OpenAirDocs)
- Category: Airplane
- Serial number: 27-7305030
- Airframe hours: 2594
- Engines: LYCOMING TIO-540 250 horsepower reciprocating
- Damage: Substantial damage
- Flight: Part 91
- Operator: Thomas G. Pelz
- Registered owner: Thomas G. Pelz
- Airworthiness certificate: Standard, Normal
- Last inspection: Annual, August 20, 1991, 13 hours before
- Airport: 47C, Boscobel, runway 1, 3,710 × 58 ft, asphalt

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 49; private; airplane ratings: single-engine land; medical: class 3, valid medical--no waivers/lim.; seat: left; flight hours: 544 total, 38 in this make and model, 450 as pilot in command, 2 in the last 30 days, 1 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Visibility: 15 statute miles
- Lowest ceiling: none
- Temperature: 54 °F

## 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 19910920046829A](https://openairdocs.org/incident/19910920046829A), Sep 20, 1991: Piper PA23250, Boscobel, WI, Substantial damage. On MEL flight test. Gave engine out. Reported power loss. Unable to detect which engine. Misused emergency gear.

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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