N8910UBeech 95-B55 (T42A) · 1965

On July 24, 2019, about 1420 mountain daylight time, a Beech 95-B55 airplane, N8910U, was destroyed when it was involved in an accident near Chadron, Nebraska. The pilot, pilot-rated-passenger, and second passenger were fatally injured. The airplane was operated as a Title 14 Code of Federal Regulations (CFR) Part 91 personal flight.

The airplane departed Fond du Lac County Airport (FLD), Fond du Lac, Wisconsin, for the 640 nautical mile (nm) cross-country flight to Chadron Municipal Airport (CDR), Chadron, Nebraska. A witness watched the accident airplane depart from FLD and reported that the airplane taxied for takeoff and that, due to airplane traffic on the ground, there was a slight delay taxiing of more than 10 minutes.

Flight track data revealed portions of the flight from FLD to CDR. The flightpath proceeded through areas of poor radar coverage, and some of the flight track was not recorded. At 1022, the flight track was recorded 1.25 nm northwest of FLD at 1,475 ft mean sea level (msl), heading west. The track continued generally west at a cruise altitude of about 8,000 ft msl until 1348, when the track data was lost about 22 nm northwest of Valentine, Nebraska. About 1408, the flight track resumed for less than 3 minutes, during which time the airplane’s altitude decreased from 8,125 ft msl to 7,300 ft msl and its ground speed was 174 kts. About 1417, the track resumed about 12 nm northeast of CDR with the airplane’s altitude at 6,050 ft msl and ground speed at 158 kts.

The pilot was in contact with air traffic control during the flight. The pilot reported 40 nm east of CDR and requested to descend to 6,000 ft, advising that he could provide his own terrain avoidance. The controller instructed the pilot to descend to 6,000 ft. The pilot stated he had the CDR weather and would be requesting the visual approach to runway 21. The pilot reported CDR in sight and canceled the instrument flight rules (IFR) flight plan. The controller acknowledged the IFR cancellation and instructed the pilot to squawk VFR. There were no further communications with the pilot.

A witness who was near the main terminal at CDR stated that he observed the airplane in the traffic pattern on the east side of runway 21. The airplane appeared to be on the left base leg for runway 21 as it made a left turn. At the end of the left turn, the airplane nosed straight down and did not pull up. The airplane wreckage was located just outside of the airport property.

Another witness who was in her residence 0.24 nm northeast of the accident site stated that she heard the airplane’s engine “sputter” as if it lost power. She added that the sound from the airplane was a lot louder than the normal airplane traffic over her house.

The fuel system consisted of a 142-gallon (136 usable gallon), noninterconnected design with two inboard main fuel tanks (37 gallons per tank) and two outboard auxiliary fuel tanks (31 gallons per tank). Each tank contained two independent float-type transmitter units, which provided indications to the cockpit fuel quantity gauges. The gauges indicated the amount of the fuel in either the main or auxiliary tanks for their respective wings. A two-position selector switch on the pilot subpanel determined the tanks, main or auxiliary, to which the indicators were connected. Therefore, one gauge shows the fuel quantity for main or auxiliary at one time, and the pilot must use the switch to change the gauges to the other set of tanks. All four fuel tank quantities cannot be viewed simultaneously.

A review of the airplane’s maintenance records did not show any logbook entries related to the fuel gauges or transmitters.

The airplane was equipped with a Shadin fuel flow indicator, which is a digital fuel management system designed to provide fuel management information under real-time flight conditions to the flight crew. The unit did not interface with the airplane’s fuel quantity indicating system and required the flight crew to enter the initial fuel on board the airplane.

The pilot had completed a weight-and-balance calculation for the accident flight, which included 259 lbs of cargo in four separate locations and a takeoff weight of 4,823.98 lbs. The calculated center of gravity was 85.43 inches aft of datum, which was within the limitations of the flight envelope.

A line service employee at FLD stated that on July 22, he drove the fuel truck at FLD and serviced the airplanes with green fuel cards attached. The accident airplane had a green card hanging on the propeller, on which the pilot requested that the main and auxiliary fuel tanks be topped off. The employee noted on the fuel card that the auxiliary tanks were already full. He added that because he made the notation “aux were full” on the fuel card, the pilot likely wasn’t present at the time; otherwise, he would have just told him in person and not made the notation.

Historical winds aloft along the route of flight showed a left quartering headwind, which varied from 10 to 18 kts, for most of the flight.

The fuel system consisted of a 142-gallon (136 usable gallon), noninterconnected design with two inboard main fuel tanks (37 gallons per tank) and two outboard auxiliary fuel tanks (31 gallons per tank). Each tank contained two independent float-type transmitter units, which provided indications to the cockpit fuel quantity gauges. The gauges indicated the amount of the fuel in either the main or auxiliary tanks for their respective wings. A two-position selector switch on the pilot subpanel determined the tanks, main or auxiliary, to which the indicators were connected. Therefore, one gauge shows the fuel quantity for main or auxiliary at one time, and the pilot must use the switch to change the gauges to the other set of tanks. All four fuel tank quantities cannot be viewed simultaneously.

A review of the airplane’s maintenance records did not show any logbook entries related to the fuel gauges or transmitters.

The airplane was equipped with a Shadin fuel flow indicator, which is a digital fuel management system designed to provide fuel management information under real-time flight conditions to the flight crew. The unit did not interface with the airplane’s fuel quantity indicating system and required the flight crew to enter the initial fuel on board the airplane.

The pilot had completed a weight-and-balance calculation for the accident flight, which included 259 lbs of cargo in four separate locations and a takeoff weight of 4,823.98 lbs. The calculated center of gravity was 85.43 inches aft of datum, which was within the limitations of the flight envelope.

A line service employee at FLD stated that on July 22, he drove the fuel truck at FLD and serviced the airplanes with green fuel cards attached. The accident airplane had a green card hanging on the propeller, on which the pilot requested that the main and auxiliary fuel tanks be topped off. The employee noted on the fuel card that the auxiliary tanks were already full. He added that because he made the notation “aux were full” on the fuel card, the pilot likely wasn’t present at the time; otherwise, he would have just told him in person and not made the notation.

The accident site was located 0.25 nm north-northeast of runway 21 in a tree line next to a field. The wreckage debris path was scattered on a 270° heading, and the airplane came to rest aligned on a 180° heading. The figure shows an aerial view of the main wreckage as it came to rest upright.

Figure – Aerial view of accident site

Examination of the wreckage revealed that the airplane descended into the tree line in a left-wing-low, nose-down flight attitude and then impacted the field. Large pieces of the flight control surfaces were found in the trees and in the wreckage path. The right wing remained in one piece and was partially attached to the fuselage. The fuel tanks were all breached. There was no odor of fuel at the accident site and no fuel blighting around the wreckage. The left fuel gauge was impact separated from the instrument panel and was found in the grass next to the fuselage. The left fuel gauge indicated empty, and the right fuel gauge indicated slightly above empty. The left fuel selector valve was found positioned to the left main fuel tank. The right fuel selector valve was found positioned on the right main fuel tank. About 3 ounces of fuel were drained from the right fuel strainer assembly. The left fuel strainer assembly was not examined due to impact damage.

A small amount of fuel was observed in both of the fuel manifold valves for each engine. The right engine throttle body/fuel metering unit screen was removed and free of obstruction. A very small amount of fuel was observed coming from the metering unit. About 1-2 ounces of fuel were found in the left engine-driven fuel pump supply line. The left engine throttle body/fuel metering unit screen was removed and free of obstruction; no fuel was noted. Disassembly and examination of each engine did not reveal any mechanical malfunctions that would have precluded normal operation.

The left propeller remained attached to the engine. One blade remained straight and exhibited light chordwise scratches and paint burnishing on the cambered side. The other blade was bent aft around the cowling; outboard of the bend, the blade remained straight with no twisting or curling. The right propeller had separated from the right engine and came to rest under the fuselage embedded in soil. One blade was straight and exhibited no rotational impact signatures. The other blade was bent aft around the cowling; it remained straight outboard of the bend and did not exhibit rotational impact signatures.

The fuel system, fuel quantity transmitters, and fuel bladders were examined. Several of the fuel cell liner to stringer clips were found unclipped. The transmitters were old and likely original to the airplane. The transmitter safety wires were not consistent; some had the wrong wire, and some had Phillips-head screws, which were incorrect for securing safety wire. The fuel quantity transmitters were measured for proper resistance during range of travel; of the 19 different transmitter electrical resistance checks, only 3 were within the manufacturer’s specified design limits.

The cargo from the wreckage was weighed, the weight and balance was recalculated based on the pilot's calculations and the approximate location of where the cargo was found in the airplane. The total cargo weight was about 410 lbs. With the additional cargo weight, the airplane would have still remained within the limitations of the flight envelope.

Shadin Fuel Flow Indicator

When the Shadin fuel flow indicator was powered on in the National Transportation Safety Board Vehicle Recorders Laboratory, the device showed the value of "0.0" for both fuel used and fuel remaining. Due to the extensive damage to the device, the preaccident operating condition of the device could not be determined.

Garmin GPS

The Garmin device did not contain any track data, as the track recording capability of the device had been turned off.

Fuel Planning

For flight in day visual flight rules (VFR) conditions, 14 CFR 91.151 states that no person may begin a flight unless (considering wind and forecast weather conditions) there is enough fuel to fly to the first point of intended landing and, assuming normal cruising speed, to fly after that for at least 30 minutes.

The airplane consumed 24 to 30 gallons per hour (gph) depending on the stage of the flight and about 26 gph at normal cruising speed. The pilot's flight planning navigation logs showed that he would depart with 134 gallons, then planned for a fuel stop at either Gordon Municipal Airport (GRN), Gordon, Nebraska, or CDR. The flight to GRN was about 40 nm shorter than to CDR, and according to his flight planning, would have required 8 less gallons of fuel than if he chose CDR. The estimated fuel consumption to CDR was 117 gallons, which would have left 17 gallons remaining.

Postaccident calculations of the fuel required for the VFR flight indicated that a minimum of 117 gallons was needed, with 13 gallons in reserve, for a total of 130 gallons.

Fuel Quantity System Maintenance Guidance

The Beech 55 annual inspection guide specified checking "for proper operation and unusual fluctuations" of fuel quantity gauges. The Beech maintenance manual recommended fuel quantity transmitters be overhauled or replaced as necessary.

The NTSB is aware that, based on this accident and other fuel-related accidents involving resistance-type fuel quantity gauging systems, the FAA is working on an Special Airworthiness Information Bulletin (SAIB) addressing all aircraft with such systems.

American Bonanza Society Magazine Article

In June 2019, the American Bonanza Society Magazine published an article titled “What I Won’t Do” reminding pilots of prudent actions when refueling and noting the following:

Whenever possible, personally fuel your airplane, or watch it being refueled. Ensure that the proper type and quantity of fuel is added in the tanks you want it put into. Compare the fuel bill to your expectations. Check the amount of fuel that was added against the amount you thought you would need. If there is a big discrepancy, figure it out, whether less fuel than you expected was put in or you needed more than you thought because your fuel tracking was flawed on prior flights.

Ensure your fuel gauges are accurate. Our Australian friends are required to have their fuel gauges calibrated .... and a placard next to the gauges that show the instrument error for each marking on the gauges (similar in concept to a compass correction card). It is possible for our fuel gauges to be reliable.

An autopsy of the pilot was performed by Western Pathology Consultants, PC, Scottsbluff, Nebraska. The cause of death was multiple blunt force injuries. Toxicology testing of specimens from the pilot performed by the FAA Forensic Sciences Laboratory did not identify any drugs or tested-for substances.

An autopsy of the pilot-rated-passenger was performed by Western Pathology Consultants, PC, Scottsbluff, Nebraska. The cause of death was multiple blunt force injuries. Toxicology testing of specimens from the pilot-rated-passenger performed by the FAA Forensic Sciences Laboratory did not identify any drugs or tested-for substances.