ERA22LA254

NTSB accident investigation · Cirrus Design SR22 · Tredyffin, PA · June 1, 2022

Accident · Serious injuriesClass 3 · LimitedFinal report
Date
June 1, 2022, 15:27 local (19:27 UTC)
Place
Tredyffin, PA
Injuries
2 serious
Damage
Substantial damage
Phase of flight
Approach
Aircraft
N432CPCirrus Design SR22
Defining event
Approach: Loss of engine power (partial)
Weather
Visual (VMC) · Day
Status
Completed
Report
Approved by Office Director
Investigation class
Class 3
NTSB office
Eastern Region Aviation
Parties
Cirrus aircraft, FAA/FSDO
FAA report
20220601009239A
Case key
105170

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 loosening of the throttle arm from the throttle body, which resulted in the pilot’s inability to control the engine, and a subsequent forced landing.

Findings · 1

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.

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 pilot while approaching the destination airport, the engine did not respond when he advanced the throttle. He also noted that the throttle felt “loose” and further described that the engine was still running, but that the rpm would not change. There was not sufficient engine power being produced in order for the airplane to reach the destination airport, so the pilot elected to perform an off-airport landing to a golf course. The airplane was substantially damaged during the landing, and the pilot and passenger were seriously injured. A postaccident examination of the engine found that the engine’s controls were damaged during the accident sequence and had separated from the engine. Additionally, the throttle arm was found loosely attached to the shaft at the throttle body. The nut needed to be tightened by 1/8-turn in order to fully engage. No other anomalies were noted during the examination that would have precluded normal operation of the engine. Review of the airplane’s maintenance records revealed that the engine controls had been inspected and lubricated about 7 months and 37 flight hours before the accident, with no subsequent maintenance to those components noted. Based on the pilot’s description that the engine did not respond to throttle changes and that it felt “loose,” as well as the finding that the throttle arm was found loosely attached to the throttle shaft, it is likely that the loosening of the securing nut resulted in the pilot’s inability to control the engine, and the subsequent forced landing.

Factual narrative

On June 1, 2022, about 1527 eastern daylight time, a Cirrus SR22, N432CP, was substantially damaged when it was involved in an accident near Wings Field Airport (LOM), Philadelphia, Pennsylvania. The private pilot and passenger received minor injuries. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. The pilot reported he departed from Georgetown Regional Airport (GGE), Georgetown, South Carolina on an instrument flight plan to LOM. The climb and en route cruise portions of the flight were uneventful. During the approach to LOM, the pilot requested the RNAV6 approach. Clearance was granted to proceed to Modena (MXE) VOR at 3,000 ft, then he was cleared for the approach to LOM. The pilot began a normal approach on autopilot, and upon reaching the final approach fix, started the descent. The pilot reported that he reduced power during the final descent, and as he attempted to increase power, the engine did not respond to throttle commands. He said that the engine was still running, but when he moved the throttle forward, the engine rpm did not increase and that the throttle lever felt “loose.” The airplane did not have enough power to make it to LOM, and the pilot decided to make a controlled, off-airport landing. The pilot subsequently performed a forced landing to a golf course. After touchdown, the airplane collided with trees at the edge of a grassy area. Postaccident examination of the airplane by a Federal Aviation Administration inspector revealed the airplane sustained structural damage to the left wing and forward fuselage, and that the empennage was partially detached. An examination of the engine confirmed valvetrain continuity throughout the engine. No abnormalities were noted with the airplane’s ignition system. The oil system exhibited a broken turbocharger oil supply line that appeared to be impact-related as oil spillage was observed directly under the broken line. Both the upper and lower engine cowlings were inspected with no additional indication of oil leakage. During the inspection, the throttle lever was removed and examined in detail, with no defects were noted. The throttle lever was then reinstalled. Throttle and mixture continuity checks were performed; however, both cables had sustained impact damage and were broken away from the engine. The throttle lever at the throttle body was slightly loose on the throttle shaft, which allowed the lever to slip with observed “ratcheting.” The throttle lever attaching nut (which featured a single-use integral locking mechanism) was loose and needed to be tightened approximately 1/8-turn to fully engage. The left wing displayed damage consistent with tree impact during the landing, and the area surrounding the wing root was damp and smelled of fuel. The left wing fuel tank contained about 1 to 2 pints of residual fuel, and about 1 pint of fuel leaked from the left wing root area during the recovery from the accident site. The right fuel tankhad about 20 gallons of fuel. The fuel samples taken from both fuel tanks showed no indication of water or contamination. The fuel selector was found in the left tank position, with no fuel found in the fuel lines or fuel distributor. Residual fuel was found in the fuel line between the fuel manifold and the throttle body. A flight control continuity check found continuity in the elevators and rudder. Both outer aileron quadrants were bent forward, separating the spherical bearing from the aileron drive pin on each side, which prevented a continuity check of the aileron system. The airplane’s most recent annual inspection was completed on October 5, 2021, at an airframe total time of 1,293 hours (about 37 flight hours before the accident). The engine maintenance log entry for the inspection noted, in part, “Inspected and lubricated all engine controls.” No inspections or maintenance of the airplane’s engine controls were noted after that date.

Aircraft

Registration
N432CP
Reported as
Cirrus Design SR22
Category
Airplane
Serial number
3254
Built
2008
Airframe hours
1,330.2
Engine
Continental IO-550N, 300 horsepower, reciprocating
Damage
Substantial damage
Flight
Personal · Part 91
Airworthiness certificate
Standard, Normal
Departed
FMY · Fort Myers, FL
Destination
1234 · Georgetown, SC
Flight plan
IFR
Equipment
Electronic multifunction display, ADS-B, Electronic primary flight display

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
70
Injuries
Serious
Certificates
Remote, Private
Airplane ratings
Single-engine land
Instrument ratings
Airplane
Medical
Class 3, With waivers/limitations
Seat
Left
Restraint
3-point
Flight hours
1,932 total · 750 in this make and model

Weather

Conditions
Visual (VMC) · Day
Wind
130° at 8 knots
Visibility
10 statute miles
Lowest ceiling
None
Temperature
82 °F, dew point 68 °F
Altimeter
29.85 inHg
Observed at
KLOM, 9 nm away
METAR
METAR KLOM 012015Z AUTO 13008KT 10SM CLR 28/20 A2985 RMK AO2 T02820198

Docket · 12

The files NTSB released with the investigation on June 20, 2024, on NTSB’s docket system: statements, records, photos and specialists’ reports. 13.9 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.