ERA22LA302

NTSB accident investigation · Air Tractor AT-502B · Center Cross, VA · July 8, 2022

Accident · No injuriesClass 3 · LimitedFinal report
Date
July 8, 2022, 15:30 local (19:30 UTC)
Place
Center Cross, VA
Injuries
1 uninjured
Damage
Substantial damage
Phase of flight
Maneuvering
Aircraft
N50075Air Tractor AT-502B
Defining event
Maneuvering-low-alt flying: Unknown or undetermined
Weather
Visual (VMC) · Day
Status
Completed
Report
Approved by Office Director
Investigation class
Class 3
NTSB office
Eastern Region Aviation
Parties
Transportation Safety Board of Canada, Pratt and Whitney Canada, FAA/FSDO
FAA report
20220708007169A
Case key
105439

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

A loss of engine power for reasons that could not be determined.

Findings · 4

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.

Engine (turbine/turboprop)Aircraft › Aircraft power plant · Unknown/Not determinedAir Tractor AT-502B: 3 casesAll aircraft: 67 casesProbable cause
Performance/control parameters: altitudeAircraft › Aircraft oper/perf/capability · Attain/maintain not possibleAir Tractor AT-502B: 19 casesAll aircraft: 1,310 cases
Performance/control parameters: landing flareAircraft › Aircraft oper/perf/capability · Attain/maintain not possibleAir Tractor AT-502B: 3 casesAll aircraft: 1,285 cases
Terrain: rough terrainEnvironmental issues › Physical environment · Contributed to outcomeAir Tractor AT-502B: 3 casesAll aircraft: 442 cases

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

The pilot reported that the airplane was fueled before beginning the agricultural application flight. About an hour into the flight, the pilot was climbing the airplane following a spray pass when he heard a “bang” and the engine lost power about 350 ft above ground level (agl). The pilot maneuvered the airplane for a forced landing and stated that the airplane touched down with too much speed. It subsequently bounced and continued into trees, resulting in substantial damage to the airframe. Postaccident examination of the wreckage revealed that there was fuel on board, and examination of the engine did not reveal evidence of any mechanical anomalies that would preclude normal operation. The power turbine blade displayed some rubbing indicative of rotation of the power section at the time of impact; however, the rubbing damage was limited and was consistent with low or reduced power. The reason for the loss of power could not be determined based on the available information.

Factual narrative

On July 8, 2022, about 1530 eastern daylight time, an Air Tractor AT-502B, N50075, was substantially damaged when it was involved in an accident near Center Cross, Virginia. The commercial pilot was not injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 137 agricultural flight. According to the pilot, before the spraying operation the airplane was fueled at Crabbe Airport (3NR4) Elizabeth City, North Carolina, before he flew to the staging airport in Tappahannock, Virginia, where he topped off the airplane with fuel and had it filled it with agriculture chemicals. Shortly after completing the final spray pass of the sixth load of the day, he turned and climbed about 350 ft agl when he heard a “bang,” and he could feel the engine lose power. He was unable to maintain altitude. The pilot lowered the airplane’s nose and maneuvered for a forced landing in an open area between trees. The pilot stated that the airplane’s speed was “too high” upon touchdown; the airplane bounced, and subsequently impacted trees and terrain before coming to rest upright. Examination of the airplane by a Federal Aviation Administration (FAA) inspector revealed that the fuselage was buckled, the leading edges of both wings were crushed, and the right elevator was bent upward. The fuel tanks remained intact. When the airplane was moved during recovery, fuel flowed from the left and right wing root areas; the fuel was confirmed to be Jet-A. Flight control continuity was confirmed to all flight control surfaces from the cockpit. The rudder remained attached, and the vertical stabilizer was bent at a 90° angle to the right about midspan. The right flap was retracted, and the left flap appeared to be partially extended at a slight angle. The left wing was partially displaced. Continuity of the engine and propeller controls was confirmed. No engine debris were located within the exhaust or intakes; there was no sign of catastrophic engine failure. A detailed examination of the engine components and accessories revealed that rotation of the power section was not possible. Smooth and noise-free rotation of the compressor was possible using the accessory gear box. The pneumatic lines were found intact and secured and the filter was free of contamination. The power turbine control was in good condition. The chip detectors, oil filter, and fuel filter were free of contamination. Closer examination of the propeller blades revealed that each exhibited features consistent with some rotation at impact. Two propeller blades exhibited chordwise/rotational abrasion. One blade was bent aft and twisted towards low pitch near the tip. Another blade was bent aft about 90 deg and exhibited wave bends in the leading edge consistent with tree/branch strikes. The third blade was fractured about 10-12 inches from the tip. The damage was consistent with rotation and not feathered at impact. One blade tip of the compressor turbine was broken and found adjacent to theblade indicative of impact damage. The power turbine section was in good condition and the blade tips displayed evidence of rubbing on the adjacent turbine shroud. The compressor rotated freely and was free of any abnormal noise or limitations. There was no visible damage present. The reduction gearbox rotated freely and displayed no evidence of defect. The fuel pump and fuel control unit could not be evaluated. Fuel was discovered in the engine compartment filter drain. The fuel selector valve contained residual fuel and operated normally between the detents with no binding or limitations and the detents were distinctive. Based on the engine and component examination, there was no indication of any pre-impact mechanical anomalies.

Aircraft

Registration
N50075
Reported as
Air Tractor AT-502B
Category
Airplane
Serial number
502B-0494
Built
1998
Airframe hours
10,407
Engine
Pratt & Whitney PT6A-34AG, 500 horsepower, turbo prop
Damage
Substantial damage
Flight
Aerial application · Part 137
Operator
Bank Of Utah Trustee
Registered owner
Bank Of Utah Trustee
Airworthiness certificate
Special, Restricted (Special); Standard, Normal
Last inspection
100 hour · February 1, 2022
Departed
XSA · Tappahannock, VA
Destination
Same as departure
Equipment
Electronic multifunction display, Auto-pilot, ADS-B, Stall warning system

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
35
Injuries
Minor
Certificates
Flight instructor, Commercial
Airplane ratings
Single-engine land
Instrument ratings
Airplane
Medical
Class 2
Last flight review
March 1, 2022
Seat
Single
Restraint
4-point
Flight hours
4,900 total · 3,100 in this make and model · 100 in the last 90 days

Weather

Conditions
Visual (VMC) · Day
Wind
170° at 6 knots
Visibility
10 statute miles
Lowest ceiling
None
Temperature
84 °F, dew point 70 °F
Altimeter
30.02 inHg
Observed at
FYJ, 17 nm away
METAR
METAR KFYJ 081835Z AUTO 17006KT 10SM CLR 29/21 A3002 RMK AO1 T02910214=

Docket · 9

The files NTSB released with the investigation on July 5, 2024, on NTSB’s docket system: statements, records, photos and specialists’ reports. 240 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 N50075 · 1

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