WPR20LA308

NTSB accident investigation · Piper PA 30 · Billings, MT · September 12, 2020

Accident · Serious injuriesClass 3 · LimitedFinal report
Date
September 12, 2020, 11:43 local (17:43 UTC)
Place
Billings, MT
Injuries
1 serious
Damage
Substantial damage
Phase of flight
Approach
Aircraft
N7602YPiper PA 30
Defining event
Approach: Fuel exhaustion
Weather
Visual (VMC) · Day
Status
Completed
Report
Approved by Office Director
Investigation class
Class 3
NTSB office
Western Pacific Region
Parties
Piper Aircraft, Federal Aviation Administration
FAA report
20200912012809A
Case key
101981

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

On this page

Probable cause

The pilot’s improper fuel planning, which resulted in a total loss of engine power due to fuel exhaustion.

Findings · 2

NTSB’s coded findings. Those marked are part of the probable cause; the rest are factors or other findings. Under each, the cases with the same finding.

Fluids: fuelAircraft › Fluids/misc hardware · Fluid managementPiper PA-30: 14 casesAll aircraft: 1,695 casesProbable cause
Planning/preparation: fuel planningPersonnel issues › Task performance · PilotPiper PA-30: 5 casesAll aircraft: 719 casesProbable cause

Sequence of events

The events NTSB coded, in order, by phase of flight. The defining event is the one that best describes the accident. Under each, the cases with the same event anywhere in their sequence.

Analysis

According to the FAA, the pilot contacted the air traffic control tower at the destination airport and requested clearance to land on runway 28. The pilot mentioned that the airplane had one engine “out” but did not share details, nor did he declare an emergency. As the airplane was on short final, the pilot made another radio call to the tower indicating that he lost the second engine. The airplane landed short of the runway against a cliffside. On scene law enforcement reported that they did not smell fuel at the accident site, nor was fuel present in the unbreeched fuel tanks. Postaccident examination of the airframe and both engines did not reveal any anomalies that would have precluded normal operations. The pilot does not recall the accident; however, he recalls that he had an issue with the right engine and had to shut it down. Estimated fuel calculations were completed assuming the fuel tanks were full and 75% power was used. The airplane would have consumed 77.4 gallons of the 84 usable gallons during the 4.5 hr accident flight. The calculations did not account for variables such as engine leaning, wind, climb, or descent. Taking those variables into account, it is likely that the airplane did not have enough fuel to complete the flight.

Factual narrative

On September 12, 2020, about 1143 mountain daylight time, a Piper PA-30 airplane, N7602Y, was substantially damaged when it was involved in an accident near Billings Logan International Airport (BIL). The airline transport pilot was seriously injured. The airplane was operated as a Title 14 Code of Federal Regulations (CFR) Part 91 personal flight. The pilot does not recall the accident; however, he recalls that he had an issue with the right engine and had to shut it down. The airplane departed Lake Elmo Airport (21D), St. Paul, Minnesota, and was destined for BIL. According to the FAA, the pilot contacted the BIL air traffic control tower asking for clearance to land on runway 28. In addition, the pilot mentioned that the airplane had one engine “out” but did not share details, nor did he declare an emergency. As the airplane was on short final, the pilot made another radio call to the tower indicating that he lost the second engine. The airplane landed short of the runway against a cliffside. On-scene law enforcement reported that they did not smell fuel at the accident site, nor was fuel present in the fuel tanks. Postaccident examination of the airframe did not reveal any anomalies that would have precluded normal operations. Flight control continuity was established throughout. All of the fuel caps were loose in their filler necks; however, the cap seals were pliable and undamaged. No fuel was present in any of the fuel bladders. The fuel strainers were drained, and a small amount of uncontaminated fuel exited. The strainer bowls were removed, and no anomalies were noted. The fuel selector valve hands were undamaged; they moved freely by hand and exhibited normal detents. The auxiliary pumps would not operate when the switch was in the ON position. The airplane structure near the pumps exhibited extensive damage and the pumps were unable to be examined. Examination of both engines did not reveal any anomalies that would have precluded normal operations. All upper spark plugs were removed and exhibited normal operating wear signatures. All cylinder rocker covers were removed, and the valves were lubricated with a light brown oil. The crankshaft was rotated by hand on both engines; thumb compression was obtained on all cylinders and the valves moved accordingly. In addition, spark was obtained from each ignition lead. The right engine propeller assembly was found in the feathered position, and the spinner exhibited impact damage to one side. One blade was bent about midspan and exhibited multidirectional scuffing near its leading edge. The other propeller blade exhibited damage consistent with recovery. The left engine propeller assembly was found in the low pitch position. One blade was bent aft near the shank and exhibited scuff marks on its cambered side near the leading edge. The other blade was unremarkable. Estimated fuel calculations were completed for full fuel tanks. The accident flight was about 4 hours and 31-minutes long.According to the Piper Twin Comanche Owner’s Handbook, the airplane’s fuel capacity is 84 gallons of usable fuel, and it would have consumed about 77.4 gallons when operated at 75% power. The calculations did not account for variables such as engine leaning, wind, climb, or descent.

Aircraft

Registration
N7602Y
Reported as
Piper PA 30 (No Series)
Category
Airplane
Serial number
30-672
Built
1964
Airframe hours
4,736
Engines
Lycoming IO-320 SERIES, 160 hp, reciprocatingLycoming IO-320 SERIES, 160 hp, reciprocating
Damage
Substantial damage
Flight
Personal · Part 91
Airworthiness certificate
Standard, Normal
Last inspection
Annual · May 15, 2020
Departed
21D · St. Paul, MN
Destination
Same as departure
Flight plan
IFR
Airport
KBIL · Billings Logan International Airport, runway 28R, 10,518 × 150 ft, asphalt
Equipment
ADS-B

Matched to the registry by N-number and the event date; the registry’s history has gaps, so older matches can be wrong. Compare the reported make and model.

Flight crew

As NTSB recorded them. NTSB leaves out names.

Role
Pilot
Age
67
Injuries
Serious
Certificates
Commercial, Airline transport
Airplane ratings
Multi-engine land, Single-engine land
Instrument ratings
Airplane
Medical
Class 1, With waivers/limitations
Last flight review
March 23, 2020
Seat
Left
Restraint
Lap only
Flight hours
18,024 total · 820 in this make and model · 15 in the last 90 days · 15 in the last 30 days · 0 in the last 24 hours

Weather

Conditions
Visual (VMC) · Day
Wind
210° at 9 knots
Visibility
10 statute miles
Lowest ceiling
None
Temperature
75 °F, dew point 32 °F
Altimeter
30.04 inHg
Icing
Clear
Observed at
BIL, 1 nm away

Docket · 10

The files NTSB released with the investigation on June 22, 2022, on NTSB’s docket system: statements, records, photos and specialists’ reports. 214 MB 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.

Other investigations on N7602Y · 2

Matched to the same aircraft by N-number and date.