IAD02LA079

NTSB accident investigation · Beech A-36 · West Mifflin, PA · August 1, 2002

Accident · No injuriesLimited investigationFinal report
Date
July 31, 2002, 20:45 local (Aug 1, 2002, 00:45 UTC)
Place
West Mifflin, PA
Injuries
1 uninjured
Damage
Substantial damage
Phase of flight
Takeoff
Aircraft
N3869ZBeech A-36
Weather
Visual (VMC) · Dusk
Status
Completed · report August 26, 2003
Report
Approved by Office Director
Parties
FAA/FSDO
FAA report
20020731022249A
Case key
55351

From the NTSB’s public API. By law, NTSB reports can’t be used as evidence in lawsuits over the accident.

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Probable cause

The failure of the alternator. A factor was the pilot's inability to manually extend the landing gear.

Sequence of events

NTSB’s coding before 2008: each occurrence and phase of flight, and the causes and factors under it. The codes are defined in NTSB’s coding manual.

Airframe/component/system failure/malfunctionTakeoff
Electrical system,alternator - failure,totalCause
Miscellaneous/otherCruise
Gear extension - not successfulPilot in commandFactor
On ground/water collision with objectEmergency landing
Object - airport sign/marker

Analysis

The pilot reported that immediately after takeoff, he lost the use of the radios and other electrical equipment. The red landing gear position light remained dimly illuminated, which indicated that the landing gear was neither securely stowed or in the down and locked position. The red alternator-out warning light was also illuminated, and the ammeter registered a discharge. The pilot contacted a 911 dispatcher on his cell phone, reported his landing intentions and proceeded toward the airport. He attempted to manually extend the landing gear with the emergency landing gear extension hand crank located behind his seat, but was unable to engage the hand crank handle. Once at the airport, the pilot flew by the control tower and a controller confirmed that the landing gear were not fully extended. The pilot then flew several traffic pattern circuits before landing on a grassy area next to a runway. Upon touchdown, the airplane continued on a straight path until it collided with a runway marker, veered left, and stopped. Examination of the alternator revealed an open rotor circuit between the F1 and F2 terminals. In addition, alternator disassembly revealed an open rotor between the rotor and slip rings. According to the airplane's pilot operating handbook, an inoperative alternator would have placed the entire electrical system operation of the airplane except engine ignition on the battery, and would have been indicated by the illumination of the ALT OUT warning light and a discharge on the ammeter.

Factual narrative

On July 31, 2002, at 2045 eastern daylight time, a Beech A-36, N3869Z, was substantially damaged during an emergency landing at Allegheny County Airport (AGC), West Mifflin, Pennsylvania. The certificated private pilot was not injured. No flight plan was filed for the flight that originated at Arnold Palmer Regional Airport (LBE), Latrobe, Pennsylvania, about 2010. Visual meteorological conditions prevailed for the business flight conducted under 14 CFR Part 91.

The pilot stated that immediately after takeoff, he lost use of the radios and other electrical equipment. He noted that the red landing gear position light remained dimly illuminated, which indicated that the landing gear was neither securely stowed or in the down and locked position. The red alternator-out warning light was also illuminated, and the ammeter registered a discharge.

The pilot contacted a 911 dispatcher on his cell phone, who then contacted the Allegheny County Airport Control Tower. The pilot reported his intentions of landing at Allegheny County Airport and proceeded toward it. While en route, he attempted to manually extend the landing gear with the emergency landing gear extension hand crank located at the rear of both front seats. However, he was unable to engage the hand crank handle.

Once at the airport, the pilot flew by the control tower and a controller confirmed that the landing gear were not fully extended. The pilot then flew several traffic pattern circuits before landing on the grass area next to runway 28. Upon touchdown, the airplane continued on a straight path until it collided with a runway marker, veered left, and stopped.

A witness, who flew for a major airline, was standing on the airport ramp when he saw the airplane fly overhead about 200 feet above ground level (agl). He said all three landing gear were "three-quarters" of the way extended. The witness observed the airplane make three more passes over the airport, each time with the landing gear in the same position. On the fifth pass, the airplane approached the grass area next to runway 28 and landed. As the airplane touched down, the left main landing gear collapsed and the airplane turned left. Then, the right main landing gear and nose gear collapsed. The witness said the airplane slid for a few hundred feet before it came to rest perpendicular to the runway.

Three Federal Aviation Administration (FAA) inspectors performed an examination of the airplane after the accident. According to an inspector, the fuselage was twisted. External examination of the alternator and voltage regulators revealed that all components were intact and securely installed.

According to a mechanic, during the recovery process, the airplane was raised on jacks, and the landing gear was lowered by the manual extension system hand crank. The airplane was then towed to a hangar.

The alternator was removed and examined under FAA supervision. Examination of the alternator revealed that there was an open rotor circuit between the F1 and F2 terminals. Additionally, when the alternator was disassembled, there was an open rotor between the rotor and slip rings.

A review of aircraft maintenance records revealed that the alternator was last overhauled on April 25, 2002, and had accumulated less than 3 hours since installation.

Two voltage regulators were also removed and examined under FAA supervision. Examination of both regulators revealed no anomalies.

According to the Beechcraft Bonanza A36 Pilot Operating Handbook (POH), page 3-8, "An inoperative alternator will place the entire electrical system operation of the airplane except engine ignition on the battery. An alternator failure will be indicated by the illumination of the ALT OUT warning light, located on the instrument panel below the flight instruments."

"The warning light will not illuminate until the alternator output is almost zero. A verification of alternator malfunction would be a discharge on the ammeter."

The pilot reported a total of 1,846 flight hours, of which, 1,134 hours were in make and model.

Weather at the time of the accident included winds from 340 degrees at 5 knots, visibility 10 statute miles, scattered clouds at 5,500 feet, and broken clouds at 25,000 feet.

Aircraft

Registration
N3869Z
Reported as
Beech A-36
Category
Airplane
Serial number
E-1788
Airframe hours
2,398
Engine
Teledyne Continental IO-520-BB, 285 horsepower, reciprocating
Damage
Substantial damage
Flight
Business · Part 91
Registered owner
Daniel M. Rooney
Airworthiness certificate
Standard, Normal
Last inspection
Annual · July 27, 2002 · 3.6 hours before
Departed
LBE · Latrobe, PA
Destination
AGC · West Mifflin, PA
Airport
AGC · Allegheny County, runway 28, 1,500 × 100 ft, concrete

Flight crew

As NTSB recorded them. NTSB leaves out names.

Role
Pilot
Age
70
Injuries
None
Certificate
Private
Airplane ratings
Single-engine land
Instrument ratings
Airplane
Medical
Class 3, Valid Medical--w/ waivers/lim
Last flight review
April 14, 2002
Seat
Left
Flight hours
1,846 total · 1,134 in this make and model · 1,337 as pilot in command · 26 in the last 90 days · 17 in the last 30 days

Weather

Conditions
Visual (VMC) · Dusk
Wind
340° at 5 knots
Visibility
10 statute miles
Lowest ceiling
25,000 ft broken
Temperature
84 °F, dew point 70 °F
Altimeter
29.97 inHg
Observed at
AGC

Docket · 3

The files NTSB released with the investigation on June 24, 2003, on NTSB’s docket system: statements, records, photos and specialists’ reports. 214 KB in all.

FAA reports on this event · 1

The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.