ERA09LA450

NTSB accident investigation · Stump Bradley Kolb · Calhoun, TN · August 8, 2009

Accident · FatalLimited investigationFinal report
Date
August 8, 2009, 10:15 local (15:15 UTC)
Place
Calhoun, TN
Injuries
2 fatal
Damage
Substantial damage
Phase of flight
Maneuvering
Aircraft
N2456Stump Bradley Kolb
Defining event
Maneuvering-aerobatics: Loss of control in flight
Weather
Visual (VMC) · Day
Status
Completed · report January 7, 2011
Report
Approved by Office Director
NTSB office
Eastern Region Aviation
Parties
FAA/FSDO
FAA report
20090808016439A
Case key
74476

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 pilot’s decision to perform aerobatics at a low altitude and his failure to maintain control of the airplane while performing aerobatics.

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.

Performance/control parameters: altitudeAircraft › Aircraft oper/perf/capability · Incorrect use/operationStump Bradley KOLB M3X: 1 caseAll aircraft: 1,310 casesProbable cause
Performance/control parametersAircraft › Aircraft oper/perf/capability · Not attained/maintainedStump Bradley KOLB M3X: 1 caseAll aircraft: 1,269 casesProbable cause
Aircraft capabilityAircraft › Aircraft oper/perf/capability · Capability exceededStump Bradley KOLB M3X: 1 caseAll aircraft: 57 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 a witness, he observed the airplane climb straight up and then do a “cartwheel” and come straight down before leveling out. He watched as the airplane did this maneuver two more times. On the third time the airplane went straight up and flipped over backwards, and at about 200 feet above ground level started to spin before colliding with the ground. The airplane was not certificated for aerobatics. Examination of the airframe, engine and system components revealed no evidence of preimpact mechanical failure or malfunction. Toxicological testing detected a prescription painkiller, a prescription anti-nausea medication, and an over-the-counter antihistamine in specimens from the pilot. No blood was available, so it was not possible to estimate when the substances might have most recently been used or whether the pilot may have been impaired by one or more of the medications at the time of the accident. The pilot had neither noted the use of any medications nor the presence of any conditions requiring the use of medications at the time of his most recent application for a Federal Aviation Administration medical certificate.

Factual narrative

On August 8, 2009, at 1015 central daylight time, an experimental, amateur-built Bradley Stump Kolb M3X, N2456, was substantially damaged following a loss of control in-flight and ground impact in Calhoun, Tennessee. The certificated private pilot, who was the owner of the airplane, and a passenger were killed. Visual meteorological conditions prevailed at the time, and no flight plan was filed for the 14 Code of Federal Regulations Part 91 personal flight. The flight originated from Hardwick Field (HDI), Cleveland, Tennessee, at an undetermined time. According to a witness, who heard the airplane passing by, looked up and observed it climb straight up and then do a “cartwheel” and come straight down then level out. The pilot did this maneuver three times, however on the third time the airplane went straight up and “flipped over backwards, at about 200 feet above the ground the airplane started spinning, and then collided with the ground”. The witness contacted 911 and reported the accident. The pilot, age 53, held a private pilot certificate, with airplane single-engine land ratings. In addition, he held a third-class medical certificate issued on October 17, 2007, with no restrictions. The pilot’s most recent medical certificate indicated that he had accumulated 85 hours of flight time. The pilot’s logbook was not recovered for examination. The two-seat, high wing, fixed tricycle gear, serial number (S/N) M3X6-4-0084, was manufactured in 2008. It was powered by a Hirth rear mounted 270-hp engine and equipped with a fixed pitch composite propeller. Review of the airplane’s logbook revealed that the airplane’s last conditional inspection was performed on March 25, 2009, and had accumulated a total time of 27.2 hours. A review of the airplane’s operating limitations, item 14 states that “This aircraft is prohibited from aerobatic flight, that is, an intentional maneuver involving an abrupt change in the aircraft’s attitude, an abnormal attitude, or abnormal acceleration not necessary for normal flight.” Examination of the wreckage by Federal Aviation Administration (FAA) inspector found that the airplane had impacted trees and the ground at near vertical nose down attitude substantially damaging the engine, cockpit, wings, empennage and stabilizers. Examination of the airframe, engine and system components revealed no evidence of preimpact mechanical failure or malfunction. An autopsy was performed on the pilot on August 10, 2009, by the University of Tennessee Medical Center, University Pathologists, P.C., in Knoxville, Tennessee. The autopsy findings included, “Multiple blunt force injuries.” Forensic toxicology was performed on specimens from the pilot by the FAA Bioaeronautical Sciences Research Laboratory, Oklahoma City, Oklahoma. The toxicology report indicated that the carbon monoxide and cyanide tests were not performed. No ethanol was detected in vitreous, but Diphenhydramine, Normeperidine and Promethazine was detected in the liver andspleen. The pilot’s most recent application for 3rd class FAA Airman Medical Certificate, dated October 17, 2007, noted no medications and no conditions requiring the use of medications.

Aircraft

Registration
N2456
Reported as
Stump Bradley Kolb (M3X)
Category
Airplane, amateur-built
Serial number
M3X6-4-00084
Airframe hours
42
Engine
Hirth 3500 SER, 270 horsepower, reciprocating
Damage
Substantial damage
Flight
Personal · Part 91
Operator
Bradley Stump
Registered owner
Bradley Stump
Airworthiness certificate
Special, Experimental (Special)
Last inspection
Condition · March 28, 2009 · 15 hours before
Departed
HDI · Cleveland, TN
Destination
HDI · Cleveland, TN

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
53
Injuries
Fatal
Certificate
Private
Airplane ratings
Single-engine land
Medical
Class 3, Without waivers/limitations
Seat
Front
Toxicology
Performed
Flight hours
85 total · 42 in this make and model

Weather

Conditions
Visual (VMC) · Day
Wind
50° at 4 knots
Visibility
7 statute miles
Lowest ceiling
None
Temperature
81 °F, dew point 70 °F
Altimeter
30.23 inHg
Observed at
CHA, 28 nm away

Docket · 6

The files NTSB released with the investigation on October 7, 2010, on NTSB’s docket system: statements, records, photos and specialists’ reports. 522 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.