Sweetwater, TX, USA
N8234R
BELLANCA 17-30A
The commercial pilot stated that there were no anomalies during the preflight inspection of the airplane or before departure. At the time of departure, the left- and right-wing fuel tanks were ½ full, and the fuselage (rear) auxiliary tank was empty. About 18 minutes after departure, both communication radios began to flicker, followed by a loss of electrical power to the avionics; none of the circuit breakers were tripped. While troubleshooting, the pilot reset the alternator circuit breaker, but it did not restore electrical power. He then diverted the flight to an alternate airport, and, during final approach, the engine lost total power. The pilot located a field encircled by trees to perform a forced landing. During the approach to the field, he attempted twice to start the engine but was unsuccessful. The pilot said that he was unable to reach the field, and the airplane impacted trees with the left wing during the approach. Postaccident examination revealed the airplane's fuel tanks were intact, and the fuel caps were in place and secure. The fuel tank filler necks and bottom of the fuel caps were brown in color consistent with corrosion. The cockpit fuel tank selector was positioned to OFF, and the cockpit auxiliary fuel tank selector was positioned to RIGHT WING. The right-wing tank contained about 9 gallons of fuel; the right-wing auxiliary tank was empty; the left-wing tank contained about 1 gallon of fuel, which was an unusable amount; the left-wing auxiliary tank contained about 8 gallons of fuel; and the rear auxiliary tank was empty. The pilot did not report the positions of the fuel selectors that he had used during the flight. The fuel lines between the fuel pump and the fuel metering unit and the fuel line between the fuel metering unit and the fuel manifold valve contained no fuel. The fuel manifold cap was removed, and no fuel was present in the manifold housing. The manifold screen did not contain debris, the diaphragm was intact, and the plunger displayed no anomalies. Testing of the fuel tank sending units revealed inaccuracies in their resistive values that would have resulted in fuel gauge indication inaccuracies. The left-wing auxiliary fuel tank sending unit had no change in resistive value with float position, and the right-wing auxiliary fuel tank sending unit had minimal difference in resistive value between mid- and upper-level float positions. The left- and right-wing fuel tank sending units' resistive values at the upper limit of float travel were similar. The resistive specifications for the airplane were unknown. There was no record that the fuel senders had been replaced since the manufacture of the airplane. Both magnetos were unable to produce a spark when rotated by hand and during bench testing due to long-term wear of the magneto pick-up brushes. A degraded performance of the magneto should have been evident to the pilot during a preflight run-up check by a greater-than-normal reduction in engine speed when operating on one magneto. There was no record of a magneto inspection in accordance with the magneto manufacturer's maintenance instructions for continued airworthiness. Although it is possible that the pilot starved the engine of fuel due to improper fuel management or that the magnetos had degraded performance, based on the available information, the investigation could not determine the exact reason for the loss of engine power.
HISTORY OF FLIGHTOn October 6, 2017, at 1329 central daylight time, a Bellanca 17-30A, N8234R, experienced a total loss of electrical power, and about 18 minutes later, a total loss of engine power during cruise flight. The pilot performed a forced landing to a field near Sweetwater, Texas, where the airplane impacted trees and terrain. The pilot and passenger on board were not injured and the airplane sustained substantial damage. The airplane was registered to an individual and operated by the pilot under the Title 14 Code of Federal Regulations Part 91 as a personal flight that was operating on a visual flight rules flight plan. Visual meteorological conditions prevailed at the time of the accident. The flight originated from Midland International Air and Space Port Airport (MAF), Midland, Texas, at 1230 and was destined to Abilene Regional Airport (ABI), Abilene, Texas but diverted to Avenger Field Airport (SWW), Sweetwater, Texas, after the loss of engine power. A written statement from the pilot regarding the accident was provided to the Federal Aviation Administration. A National Transportation Safety Board Pilot/Operator Aircraft Accident/Incident Report, Form 6120.1, was not received from the pilot. The pilot stated that there were no anomalies during the preflight inspection of the airplane, the taxi, runup, and departure climb from MAF. He stated that at the time of departure, the left- and right-wing fuel tanks were ½ full, and the fuselage auxiliary tank was empty. About 18 minutes after departure, both communication radios began to flicker followed by a loss of electrical power to the avionics; none of the circuit breakers were tripped. In troubleshooting, the pilot reset the alternator circuit breaker, which did not restore electrical power. He then diverted the flight to SWW and entered a right downwind for runway 17 at 700 feet above the airport traffic pattern altitude. He said that he attempted but was unable to extend the flaps and did not receive a landing gear down and locked indication. He extended the downwind leg and slowed the airplane to 90 knots indicated airspeed to perform an emergency landing gear extension. He pressed the emergency gear release lever several times but felt/heard no indications that the landing gear extended. The pilot then flew an extended final and about 8 miles from runway 17, the airplane experienced a total loss of engine power. He located a field encircled by trees to perform a forced landing. During the approach to the field, he attempted twice to start the engine but was unsuccessful. The pilot said that he was unable to attain the field and the airplane impacted trees with the left wing during the approach. The airplane turned and yawed left, impacted the ground, and slid to a stop. AIRCRAFT INFORMATIONThe airplane was equipped with left- and right-wing tanks that each had a 19-gallon capacity, each of which had a 15 gallons useable capacity. The airplane was equipped with left and right auxiliary wing tanks outboard of the wing tanks with a 17-gallon capacity, each of which had a 17 gallons useable capacity. The airplane also had a fuselage auxiliary fuel tank with a total and useable capacity of 20 gallons. The airplane underwent annual inspections in 2012, 2016, and on June 17, 2017 at a total airframe time of 3,401.82 hours, an engine time since overhaul of 970.82 hours, and a tachometer time of 3,401.82 hours. The tachometer time at the time of the accident was 3,407.2 hours. AIRPORT INFORMATIONThe airplane was equipped with left- and right-wing tanks that each had a 19-gallon capacity, each of which had a 15 gallons useable capacity. The airplane was equipped with left and right auxiliary wing tanks outboard of the wing tanks with a 17-gallon capacity, each of which had a 17 gallons useable capacity. The airplane also had a fuselage auxiliary fuel tank with a total and useable capacity of 20 gallons. The airplane underwent annual inspections in 2012, 2016, and on June 17, 2017 at a total airframe time of 3,401.82 hours, an engine time since overhaul of 970.82 hours, and a tachometer time of 3,401.82 hours. The tachometer time at the time of the accident was 3,407.2 hours. WRECKAGE AND IMPACT INFORMATIONPost-accident examination of the airplane revealed that the flaps and landing gear were retracted. The propeller was attached to the engine crankshaft, and all three propeller blades were attached to the propeller hub. All the propeller blades exhibited chordwise scratches consistent with rotation. The propeller blades were able to be rotated in the hub by hand, which was consistent with broken pitch change links. Flight control continuity was confirmed from the flight control surfaces to the cockpit controls. The airplane fuel tanks were intact and not broken open. The fuel caps were in place and secure. The fuel tank filler necks and bottom of the fuel caps were brown in color consistent with corrosion. The cockpit fuel tank selector was positioned to OFF, and the cockpit auxiliary fuel tank selector was positioned to RIGHT WING. The pilot did not report the positions of the fuel selectors that he had used during the flight. During the salvage recovery of the airplane, the right-wing tank contained about 9 gallons of fuel, the right-wing auxiliary tank was empty, the left-wing tank contained about 1 gallon of fuel, and the left-wing auxiliary tank contained about 8 gallons of fuel. The rear auxiliary tank was empty. The wings had either separated from the fuselage during the accident or removed during recovery. All the fuel tank sending units were of the resistive type and were not annotated with information identifying a manufacturer, part number, or serial number. The sending units were removed, examined and tested with an Ohm meter. All the sending units' float arms moved freely under hand pressure, no binding was noted, and their electrical connections were secure and in place. The resistive test measurements yielded the following approximate resistive values for the fuel sender float positions at bottom limit of travel, mid-range, and upper limit of travel positions: Test meter resistance - 2 ohms Left wing fuel tank: bottom limit – 4 ohms, mid-range – 18 ohms, upper limit – 45 ohms Left auxiliary fuel tank: bottom limit, mid-range, upper limit – 35 ohms Right main fuel tank: bottom limit – 3 ohms, mid-range – 16 ohms, upper limit – 38 ohms Right auxiliary fuel tank: bottom limit – 6 ohms, mid-range – 37 ohms, upper limit – 49 ohms The resistive specifications for the airplane were unknown at the time this report was written. There was no record that the fuel senders had been replaced since the manufacture of the airplane. When electrical power was placed on the airplane, the communication and navigation radios powered up and no circuit breakers tripped. Electrical continuity from the battery to the alternator was confirmed. The alternator was attached, secure and had its drive belt in place, which exhibited normal belt tension. The alternator was removed, and bench tested without anomalies. The loss of electrical power was not duplicated during the examination. Post-accident engine examination revealed the fuel lines were attached and secure. The fuel lines between the fuel pump and the fuel metering unit contained no fuel. The fuel line between the fuel metering unit and the fuel manifold valve contained no fuel. The fuel manifold cap was removed, and no fuel was present in the manifold housing. The manifold screen did not contain debris, the diaphragm was intact, and the plunger displayed no anomalies. Borescope examination of the cylinders revealed no mechanical anomalies. Engine drive and valve train continuity to the accessory section was confirmed during hand rotation of the propeller with the top spark plugs removed. The top sparkplugs displayed color consistent with a lean mixture. The spark plugs displayed no lead or carbon fouling, and the electrodes displayed a normal-worn condition. During crankshaft rotation, there was a repetitive audible sound consistent with the magneto impulse coupling operation. After neither magneto produced an electrical spark, they were removed for bench testing and disassembly. The right magneto was a Slick Aircraft Products, model 6310, serial number 00091452, and the left magneto was a Slick Aircraft Products, model 6310, serial number 00091465. The head of the magneto case screw adjacent to the P-lead connection partially contained a yellow-colored material placed upon the screw head during manufacturing of the magneto. Both magnetos were placed on a test bench and rotated at 3,600 rpm and no electrical spark was produced from any of the distributor block leads due to wear of magneto pick-up brushes. The coil and condenser from both magnetos were tested using a coil and condenser tester, which resulted in no test anomalies. Slick Service Bulletin SB3-08, was issued for the mandatory inspections on all Slick 4300/6300 and LASAR 4700/6700 magnetos with serial numbers beginning with 0409XXXX and up. The Service Bulletin stated: "Field reports indicate operators have experienced premature carbon brush wear. Premature brush wear can lead to failure of the magneto to provide consistent spark and possible loss of engine power. This bulletin describes an inspection schedule for specific serial number ranges and magneto and brush operating times due to observed variations in premature wear rates. The actions required by this Service Bulletin do not provide a solution or terminating action but are aimed at detecting wear signs before damage grows and results in magneto failure." A review of the airplane and engine records for magneto maintenance revealed that the most recent recorded maintenance for either magneto was the installation of the right magneto dated October 26, 2010 as recorded on a blue tag at a tachometer time of 2,944.04 hours. There were no subsequent records showing an overhaul/inspection of either magneto.
The loss of engine power during a precautionary approach for landing for reasons that could not be determined based on the available information.
Source: NTSB Aviation Accident Database
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