CEN15LA202

NTSB accident investigation · Fairchild SA227 AC · Rifle, CO · April 17, 2015

Accident · No injuriesLimited investigationFinal report
Date
April 16, 2015, 22:45 local (Apr 17, 2015, 04:45 UTC)
Place
Rifle, CO
Injuries
1 uninjured
Damage
Substantial damage
Phase of flight
Enroute
Aircraft
N2691WFairchild SA227 AC
Defining event
Enroute-climb to cruise: Loss of engine power (total)
Weather
Instrument (IMC) · Night/dark
Status
Completed · report April 20, 2020
Report
Approved by Office Director
NTSB office
Central Region
Parties
Honeywell Aerospace, FAA Salt Lake City FSDO
FAA report
20150416004399A
Case key
91049

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 uncontained engine failure due to the fatigue failure of the second-stage turbine rotor disk.

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.

Engine (turbine/turboprop): turbine sectionAircraft › Aircraft power plant · Fatigue/wear/corrosionFairchild SA227-AC: 1 caseAll aircraft: 74 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

The commercial pilot departed in the twin-engine airplane for a scheduled, domestic cargo flight. He reported that, during the climb, he heard a "bang," which was followed by a loss of engine power and fire indications from the right engine. The pilot declared an emergency and diverted to another airport for an instrument approach and landed uneventfully. Postaccident examination of the airplane revealed that the right engine's second-stage turbine rotor had separated. One portion of the rotor exited through the left side of the engine and nacelle structure, penetrated the right side of the fuselage, and came to rest inside the fuselage wall. Other portions of the separated rotor exited through the right side of the engine. The engine and the inside of the nacelle structure exhibited fire damage, but no evidence of a sustained fire was found in that area. The examination of the turbine engine revealed fatigue cracks on the second-stage rotor disk, which indicates that the rotor disk likely failed due to fatigue, and this likely resulted in the uncontained engine failure.

Factual narrative

On April 16, 2015, about 2245 mountain daylight time, a Fairchild SA227-AC, twin-engine airplane, N2691W, operating as Key Lime flight 168, was substantially damaged after an uncontained engine failure during climb near Rifle, Colorado. The pilot was not injured. The airplane was registered to CBG LLC, Wilsonville, Oregon, and was operated by Key Lime Air Corporation, Englewood, Colorado. Dark, night, instrument meteorological conditions (IMC) prevailed at the time of the accident and an instrument flight rules (IFR) flight plan had been filed for the Title 14 Code of Federal Regulations Part 135 cargo flight. The airplane departed from Garfield County Regional Airport (RIL), Rifle, Colorado, at 2237 and was destined for Denver International Airport (DEN), Denver, Colorado The pilot reported that during a climb, when still well below the tops of nearby mountains, he heard a "bang" followed by a complete loss of power and engine fire indications from the right engine. After completing appropriate checklist items, the pilot declared an emergency and diverted to Grand Junction Regional Airport (GJT), Grand Junction, Colorado, for an instrument approach and landing at 2311. The airplane landed without further incident. A post accident examination of the airplane revealed the second stage turbine rotor from the right engine had separated. One portion of the rotor exited through the left side of the engine and nacelle structure, penetrated the right side of the fuselage, and came to rest inside the fuselage wall. Other portions of the separated rotor exited through the right side of the engine. There was thermal damage to the engine and the inside of the nacelle structure, but no evidence of a sustained fire in that area. The examination of the turbine engine noted fatigue cracks on the 2nd stage rotor disk. The rotor disk had a reported 3,901.4 hrs., and 4,143 cycles

Aircraft

Registration
N2691W
Reported as
Fairchild SA227 AC
Category
Airplane
Serial number
AC-655B
Built
1986
Airframe hours
26,855
Engines
Airesearch TPE331 SERIES, 1,100 horsepower, turbo propAiresearch TPE331 SERIES, 1,100 horsepower, turbo prop
Damage
Substantial damage
Flight
Part 135
Operator
Key Lime Air Corporation, doing business as Denver Air Connection
Registered owner
Cbg LLC
Airworthiness certificate
Standard, Commuter; Standard, Normal
Last inspection
Continuous airworthiness · February 24, 2015
Departed
RIL · Rifle, CO
Destination
DEN · Denver, CO
Flight plan
IFR
Airport
RIL · Garfield County Rgnl, runway 26, 7,000 × 100 ft, asphalt
Equipment
Stall warning system, Auto-pilot

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
28
Injuries
None
Certificate
Commercial
Airplane ratings
Single-engine land, Multi-engine land
Instrument ratings
Airplane
Medical
Class 1, With waivers/limitations
Last flight review
October 8, 2014
Seat
Left
Restraint
4-point
Flight hours
2,920 total · 1,130 in this make and model · 2,765 as pilot in command · 117 in the last 90 days · 53 in the last 30 days · 3 in the last 24 hours

Weather

Conditions
Instrument (IMC) · Night/dark
Wind
130° at 4 knots
Visibility
10 statute miles
Lowest ceiling
2,000 ft overcast
Temperature
37 °F, dew point 36 °F
Altimeter
30.04 inHg
Observed at
KRIL

Docket · 5

The files NTSB released with the investigation on October 24, 2019, on NTSB’s docket system: statements, records, photos and specialists’ reports. 7.2 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 N2691W · 1

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