ERA15LA366

NTSB accident investigation · Cessna 172 · Bally, PA · September 21, 2015

Accident · Minor injuriesLimited investigationFinal report
Date
September 21, 2015, 18:30 local (22:30 UTC)
Place
Bally, PA
Injuries
1 minor
Damage
Substantial damage
Phase of flight
Maneuvering
Aircraft
N347SPCessna 172
Defining event
Maneuvering-low-alt flying: Loss of control in flight
Weather
Visual (VMC) · Day
Status
Completed · report May 1, 2017
Report
Approved by Office Director
NTSB office
Eastern Region Aviation
Parties
FAA/FSDO
FAA report
20150921018489A
Case key
92013

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 failure to maintain altitude during low-level aerobatic maneuvers. Contributing to the accident were the pilot's improper decision to attempt the low-level aerobatic maneuvers and his impairment due to psychiatric conditions and the medications he was using to treat them.

Findings · 6

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.

Use of equip/info: aircraft controlPersonnel issues › Task performance · PilotCessna 172S: 206 casesAll aircraft: 9,295 casesProbable cause
Performance/control parameters: altitudeAircraft › Aircraft oper/perf/capability · Not attained/maintainedCessna 172S: 6 casesAll aircraft: 1,310 casesProbable cause
Mental/emotional statePersonnel issues › Psychological · PilotCessna 172S: 1 caseAll aircraft: 21 casesProbable cause
Object/animal/substance: fence/fence postEnvironmental issues › Physical environment · Contributed to outcomeCessna 172S: 7 casesAll aircraft: 313 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 commercial pilot was conducting a personal cross-country flight. Several witnesses reported observing different sequences of events. One witness reported seeing the airplane fly in a 90° right bank turn for about 10 seconds as it maneuvered underneath power lines and between two utility towers. After passing under the power lines, the airplane leveled and then impacted the ground. Another witness reported that the airplane was at a lower-than-normal altitude and seemed to be flying "erratically" and "aggressively," and that, at one point, it was "flying on its side." Another witness reported seeing the airplane flying with one wing pointing toward the ground. The witness statements are consistent with low-altitude aerobatic maneuvers. Although some bystanders reported that the engine sputtered and lost power and the pilot reported that a loss of engine power occurred, postaccident examination of the airframe and engine, which included a successful engine test run, revealed no preimpact mechanical malfunctions or failures that would have precluded normal operation. Toxicological testing of the pilot's specimens revealed that he had high levels of a sedating benzodiazepine, alprazolam, within the toxic range. Additionally, he had a low level of a second sedating benzodiazepine, lorazepam. Both these medications are used to treat significant anxiety disorders, which are associated with performance deficits, particularly in high-workload spatial tasks. It is likely that the pilot's underlying psychiatric disorders and the medications he was using to treat them impaired his judgement, executive functioning, and psychomotor skills and contributed to the accident.

Factual narrative

***This report was modified on February 28, 2017. Please see the docket for this accident to view the original report.*** ***This report was modified on July 10, 2020. Please see the docket for this accident to view the original report.*** On September 21, 2015, about 1830 eastern daylight time, a Cessna 172S, N347SP, operated by Certified Flyers, was substantially damaged during a collision with terrain, while maneuvering after takeoff from Butter Valley Golf Port (7N8), Bally, Pennsylvania. The commercial pilot incurred minor injuries. The personal flight was conducted under the provisions of 14 Code of Federal Regulations Part 91. Visual meteorological conditions prevailed and no flight plan was filed for the planned flight to Morristown Municipal Airport (MMU), Morristown, New Jersey. According to the pilot's written statement, he flew from MMU to 7N8 uneventfully. He then departed 7N8 for a return trip to MMU. During initial climb, about 800 feet above ground level, the airplane experienced a partial loss of engine power, with the tachometer indicating about 1,500 rpm. The pilot attempted to land straight ahead, but due to powerlines, he made a left descending turn. He did not think he would be able to glide the airplane back to the airport and elected to land in a nearby field. During the landing, the landing gear struck a fence and the airplane came to rest inverted in the field. Review of an emergency medical service (EMS) report revealed: "…bystanders say they heard…[the] engine sputter. From bystanders, the [pilot] flew over the high tension power lines and as the engine cut out tried to turn back towards the direction of Butter Valley. Per bystanders the plane was losing altitude quickly and dropped under the high tension lines. Once just barely clearing them, bystanders say he then had to make it through the high tension towers and did. Then the plane came down in a hard landing…" The EMS report did not identify the bystanders, but noted who a 911-caller was. During a telephone interview, the 911-caller stated that he was driving a dump truck near a farm with the windows three-fourths down. The accident airplane passed about 20 feet above his truck as it proceeded underneath powerlines and banked right on its side. Shortly thereafter, it impacted the crest of a hill. The caller added that it appeared the pilot was "having fun or showing off." The caller further stated that he could hear the engine operating, but could not make a determination of the power setting. He drove to the accident site, called 911, and attempted to assist the pilot. Another witness stated she was at her residence when she noticed a white single-engine airplane circling near her home. It was executing sharp turns, diving and then pulling up. She added that the engine sputtered and stalled at least once, but then started again, which she believed occurred when the airplane was pulling up. She further stated that she was concerned that the airplane might hit herhouse because it was flying low. The witness did not see the impact, but noted that it looked like the pilot was reckless or trying to do stunts. According to a third witness, who worked at 7N8, he saw a white airplane with a blue and yellow stripe land between 1800 and 1830. The airplane approached faster and in a tighter traffic pattern than other airplanes that he typically observed land at the airport. The airplane made a sharp turn over parked airplanes on its approach to the runway. The airplane's right wing then dipped low over the runway, but did not contact it. The wings subsequently leveled as the engine noise increased. The witness added that the airplane must have touched down further down the runway as he did not see it land, but saw it taxiing back on the runway for another takeoff. He did not see the subsequent takeoff. A fourth witness, who lived near the accident site, stated that he was in his backyard between 1815 and 1830, when he heard a small airplane, which he observed was white and yellow flying toward his property at a lower altitude than normal. The witness added that the airplane seemed to be flying erratically and at one point was "flying on its side." The witness further stated that he was concerned for the safety of the airplane and his house as he watched the abnormal flight, during which the pilot seemed to be flying aggressively for several minutes. He did not witness the impact, but added that he did not hear any abnormal engine sounds. A fifth witness, who also lived near the accident site, reported that he was sitting in his living room and noticed an airplane that was not flying normally. Specifically, one wing was pointed toward the ground and the other pointed toward the sky. The airplane then disappeared behind a fence row and dust rose in the air. The witness assumed the airplane had crashed and attempted to drive to the site and offer assistance; however, he soon saw emergency responders and concluded that they would assist. A sixth witness stated that he was working on a farm near the accident site at the time of the accident. He was operating a skid-loader at the time, and could not hear the airplane's engine noise or the lack of it. He watched the airplane fly in a 90-degree right bank turn for about 10 seconds, "wingtip to wingtip," as it maneuvered underneath powerlines and in between two utility towers. After passing under the powerlines, the airplane leveled and impacted the ground. Examination of the wreckage by a Federal Aviation Administration (FAA) inspector revealed substantial damage to the right wing, consistent with a right wing low impact, and that the nose landing gear had collapsed during impact. He observed impact marks in the soybean field, consistent with a high-angle right bank turn toward and under the powerlines. The inspector also noted a strong odor of fuel at the accident site. When the airplane was subsequently up-righted and recovered, the inspector observed that both fueltanks were almost full. A fuel sample was recovered from the engine driven fuel pump after the wreckage was recovered to a storage facility. A small amount of dirt was noted on the outside of the fuel line near the pump fitting; however, the fuel sample was consistent with 100-low-lead aviation gasoline and absent of any visible contamination. A successful test-run of the engine was subsequently performed. A fuel supply was plumbed from a container to the engine driven fuel pump due to a damaged lower fuel sump. The engine did not start on the first attempt as the electric fuel pump was damaged in the accident and could not supply fuel to prime the engine. Ether was then used as primer for the engine on the second attempt. During the second attempt, the engine started immediately and ran continuously without hesitation at multiple power settings, including full power. The engine was run for several minutes and then shut down. Toxicology testing performed by the FAA's Bioaeronautical Research Laboratory on blood and urine specimen obtained during the pilot's initial postaccident medical care identified alprazolam in blood (0.123 µg/ml) and urine as well as its metabolite, alpha-hydroxyalprazolam in urine. Lorazepam was identified in blood (0.03 µg/ml) and urine. In addition, sertraline and its metabolite desmethylsertraline were identified in urine and blood and ondansetron was found in urine. The pilot's most recent first-class medical certificate was issued on April 7, 2015. On the application for that certificate, he reported no medical conditions or medications to the FAA. Alprazolam is a benzodiazepine medication available as a Schedule IV controlled substance used to treat anxiety disorder and panic disorder. It is commonly marketed with the name Xanax. The drug information includes this instruction to providers: "Because of its CNS depressant effects, patients receiving alprazolam tablets should be cautioned against engaging in hazardous occupations or activities requiring complete mental alertness such as operating machinery or driving a motor vehicle." The usual therapeutic dose range is between 0.0060 and 0.0200 µg/ml; levels above 0.100 are considered toxic. Lorazepam is another benzodiazepine medication available as a Schedule IV controlled substance, indicated for the treatment of anxiety disorders or for the short-term relief of the symptoms of anxiety or anxiety associated with depressive symptoms. It is commonly marketed with the name Ativan. Lorazepam carries specific warnings including, "Use of benzodiazepines, including lorazepam, both used alone and in combination with other CNS depressants, may lead to potentially fatal respiratory depression. Use of benzodiazepines, including lorazepam, may lead to physical and psychological dependence. As with all patients on CNS-depressant drugs, patients receiving lorazepam should be warned not to operate dangerous machinery or motor vehicles and that their tolerance for alcohol and otherCNS depressants will be diminished. The usual therapeutic range is between 0.1600 and 0.2700 µg/ml. Sertraline is an antidepressant marketed with the name Zoloft.

Aircraft

Registration
N347SP
Reported as
Cessna 172 (S)
Category
Airplane
Serial number
172S8271
Built
1999
Airframe hours
5,542
Engine
Lycoming IO-360, 180 horsepower, reciprocating
Damage
Substantial damage
Flight
Personal · Part 91
Operator
Certified Aviation LLC
Registered owner
Certified Aviation LLC
Airworthiness certificate
Standard, Normal
Last inspection
100 hour · September 18, 2015 · 7 hours before
Departed
7N8 · Bally, PA
Destination
MMU · Morristown, NJ
Airport
7N8 · Butter Valley Golf Port, runway 34, 2,420 × 85 ft, asphalt
Equipment
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
23
Injuries
Minor
Certificates
Flight instructor, Commercial
Airplane ratings
Multi-engine land, Single-engine land
Instrument ratings
Airplane
Medical
Class 1, Without waivers/limitations
Last flight review
January 29, 2015
Seat
Left
Restraint
3-point
Toxicology
Performed
Flight hours
1,550 total · 1,300 in this make and model · 1,250 as pilot in command · 200 in the last 90 days · 75 in the last 30 days · 2 in the last 24 hours

Weather

Conditions
Visual (VMC) · Day
Wind
Calm
Visibility
10 statute miles
Lowest ceiling
11,000 ft broken
Temperature
64 °F, dew point 48 °F
Altimeter
30.20 inHg
Observed at
PTW, 11 nm away

Docket · 16

The files NTSB released with the investigation on February 13, 2017, on NTSB’s docket system: statements, records, photos and specialists’ reports. 14.6 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.