Sunday, May 10, 2020

Loss of Engine Power (Partial): Cirrus SR20, N314BF; accident occurred August 13, 2016 near Des Moines International Airport (KDSM), Iowa









































The National Transportation Safety Board did not travel to the scene of this accident.

Additional Participating Entities:
Federal Aviation Administration / Flight Standards District Office; Ankeny, Iowa
Cirrus Aircraft; Duluth, Minnesota 
Continental Motors Group; Mobile, Alabama 

Aviation Accident Factual Report - National Transportation Safety Board:  https://app.ntsb.gov/pdf

Investigation Docket - National Transportation Safety Board: https://dms.ntsb.gov/pubdms

http://registry.faa.gov/N314BF

Location: Des Moines, IA
Accident Number: CEN16LA320
Date & Time: 08/13/2016, 1001 CDT
Registration: N314BF
Aircraft: CIRRUS DESIGN CORP SR20
Aircraft Damage: Destroyed
Defining Event: Loss of engine power (partial)
Injuries: 3 Minor, 1 None
Flight Conducted Under: Part 91: General Aviation - Personal 

On August 13, 2016, about 1001 central daylight time, a Cirrus Design Corporation SR20 airplane, N314BF, had a partial loss of engine power shortly after takeoff from Des Moines International Airport (DSM), Des Moines, Iowa. The pilot deployed the Cirrus Airframe Parachute System (CAPS) and descended into power lines and terrain. The airplane was subsequently destroyed by a postimpact fire. The pilot and 2 passengers sustained minor injuries. An additional passenger was not injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight.

The pilot reported that he did not observe any airframe or engine anomalies during his preflight inspection. He also noted that the fuel tanks were completely full, and that he did not observe any contamination in the fuel samples that he obtained during his preflight inspection. The pilot reported that the engine started without hesitation and idled normally before taxi, and that he did not observe any anomalies during his before takeoff engine run-up.

A normal takeoff was made on runway 31 from the taxiway Romeo intersection with the wing flaps set at 50%, the electric fuel pump selected to boost, and the mixture-control set to full rich. The pilot reported that the engine instrumentation indicated normal readings during the takeoff run and that liftoff was achieved at 70 knots indicated airspeed (KIAS). After liftoff, the pilot reduced airplane pitch and accelerated to 90-95 KIAS before he retracted the wing flaps. The pilot reported that during the initial climb, about 500 ft above ground level (agl), he heard and felt a sudden reduction in engine power. He told the tower controller that he had engine trouble and requested an immediate landing. The tower controller cleared the pilot to enter a right downwind for landing on runway 31. The pilot reported that he was unable to maintain altitude and, as a result, he deployed the CAPS. After a successful parachute deployment, the airplane contacted power lines shortly before it impacted the ground at the intersection of Park Avenue and SW 56th Street. The pilot remarked that the airplane had landed "remarkably soft" in a nose level attitude. After landing, a fire erupted from under the left wing and the pilot told his passengers to evacuate from the right cabin door. The airplane was subsequently destroyed by the postimpact fire.

The airplane was a four-place single engine low-wing airplane of primarily composite construction. The airplane was powered by a 6-cylinder, 200 horsepower, Continental Motors IO-360-ES16B engine, serial number 1000059, which drove a two-blade Hartzell model BHC-J2YF-1BF/F7694 constant speed propeller. According to airplane logbook entries, the most recent annual inspection was completed on May 19, 2016, at 1,565.6 hours total airframe time. As of the annual inspection, the engine had accumulated 555.1 hours since it was rebuilt at the factory on March 20, 2009. A review the engine logbook only revealed one maintenance entry, dated February 10, 2012, at 181.5 hours total engine time, in which the induction system was specifically mentioned as having been inspected. However, further review the engine logbook was inconclusive if the induction system tubes had been removed for maintenance in the 7.4 years since the engine had been rebuilt. According to the pilot, the airplane had accumulated about 66.5 flight hours since the last annual inspection.

The engine and propeller were not damaged by the postimpact fire. The engine remained attached to the firewall and the propeller remained attached to the crankshaft flange. The propeller exhibited torsional twisting, S-shaped spanwise bends, leading edge damage, and burnishing of the blade face and back. Internal engine and valve train continuity was confirmed as the engine crankshaft was rotated. Compression and suction were observed on all cylinders in conjunction with crankshaft rotation, and both magnetos provided spark at all leads. The sparkplugs for cylinder Nos. 4 and 5 exhibited excessive black soot, consistent with an over-rich fuel/air mixture. The remaining sparkplugs exhibited features consistent with normal engine operation. A borescope inspection of each cylinder did not reveal any anomalies. Additionally, no anomalies were observed with the fuel servo, mechanical fuel pump, fuel flow divider, or fuel injectors. A disassembly of the oil filter did not reveal any metal debris. The induction tube coupler closest to the No. 1 cylinder, part number (p/n) 654439-16, was observed partially disconnected from its associated induction tube. Although both coupler clamps were tight, the clamp, p/n AN737TW74, closest to the No. 1 cylinder did not overlap its associated induction tube. Additionally, the cylinder No. 3 induction tube, p/n 655224-1, was fractured at the cylinder mounting flange.

The fractured No. 3 induction tube, p/n 655224-1, was submitted to the National Transportation Safety Board (NTSB) Materials Laboratory for additional examination. A visual examination confirmed that the mounting flange of the induction tube had fractured from the main body of the tube. An additional attachment flange that had been installed between the induction tube flange and the engine cylinder did not exhibit any discernible damage. Several measurements of the induction tube revealed it was deformed in multiple directions such that the measurements at various locations produced inconsistent data. The tube inner diameter measured 1.624 inches, and the outer diameter measured between 1.742 and 1.767 inches. The tube thickness ranged between 0.705 and 0.735 inches. The manufacturer drawing dimension AB measured 2.822 inches, and the AC line measured about 2.6 inches. The fracture between the flange and the remaining tube was circumferential in orientation and perpendicular to the tube direction. The flange had also fractured in two additional locations longitudinally, creating two flange fragments. In general, the mating fracture surfaces exhibited a flat orientation, with some other areas exhibiting a 45° fracture orientation. The fracture surfaces exhibited smearing and rub marks, consistent with post-fracture damage. Examination of the flange-side fracture surface with a scanning electron microscope revealed fatigue striations, consistent with fatigue crack propagation. The character and spacing of the striations were consistent with high-cycle fatigue. The likely initiation sites of the fatigue had been destroyed by the post-fracture smearing. The chemical composition of the fractured induction tube flange was determined by energy dispersive x-ray spectroscopy (EDS) and was consistent with an AA 6061-series aluminum alloy. The results of material electrical conductivity and hardness testing were consistent with those typical of the 6061-O aluminum alloy in the annealed condition. The chemical composition, electrical conductivity, and hardness values were consistent with the engine manufacturer's part specification.

Pilot Information

Certificate: Private
Age: 42, Male
Airplane Rating(s): Single-engine Land
Seat Occupied: Left
Other Aircraft Rating(s): None
Restraint Used:
Instrument Rating(s): Airplane
Second Pilot Present: No
Instructor Rating(s): None
Toxicology Performed: No
Medical Certification: Class 3 Without Waivers/Limitations
Last FAA Medical Exam: 02/08/2013
Occupational Pilot: No
Last Flight Review or Equivalent: 03/23/2016
Flight Time:  (Estimated) 252 hours (Total, all aircraft), 66 hours (Total, this make and model), 211 hours (Pilot In Command, all aircraft), 66 hours (Last 90 days, all aircraft), 37 hours (Last 30 days, all aircraft), 0 hours (Last 24 hours, all aircraft) 

Aircraft and Owner/Operator Information

Aircraft Make: CIRRUS DESIGN CORP
Registration: N314BF
Model/Series: SR20 NO SERIES
Aircraft Category: Airplane
Year of Manufacture: 2000
Amateur Built: No
Airworthiness Certificate: Normal
Serial Number: 1055
Landing Gear Type: Tricycle
Seats: 4
Date/Type of Last Inspection: 05/19/2016, Annual
Certified Max Gross Wt.: 3000 lbs
Time Since Last Inspection: 66 Hours
Engines: 1 Reciprocating
Airframe Total Time: 1632 Hours at time of accident
Engine Manufacturer: Continental
ELT: Installed, not activated
Engine Model/Series: IO-360-ES16B
Registered Owner: Alidade Partners, LLC
Rated Power: 200 hp
Operator: Alidade Partners, LLC
Operating Certificate(s) Held: None

Meteorological Information and Flight Plan

Conditions at Accident Site: Visual Conditions
Condition of Light:Day 
Observation Facility, Elevation: DSM, 958 ft msl
Distance from Accident Site: 2 Nautical Miles
Observation Time: 0954 CDT
Direction from Accident Site: 130°
Lowest Cloud Condition: Clear
Visibility:  10 Miles
Lowest Ceiling:None 
Visibility (RVR):
Wind Speed/Gusts: 8 knots /
Turbulence Type Forecast/Actual: None / None
Wind Direction: 350°
Turbulence Severity Forecast/Actual: N/A / N/A
Altimeter Setting: 29.97 inches Hg
Temperature/Dew Point: 25°C / 18°C
Precipitation and Obscuration: No Obscuration; No Precipitation
Departure Point: Des Moines, IA (DSM)
Type of Flight Plan Filed: IFR
Destination: Lebanon, OH (I68)
Type of Clearance: IFR
Departure Time: 1001 CDT
Type of Airspace: Class C

Airport Information

Airport: Des Moines International Arpt (DSM)
Runway Surface Type: Asphalt; Concrete
Airport Elevation: 958 ft
Runway Surface Condition: Dry
Runway Used: 31
IFR Approach:None 
Runway Length/Width: 9002 ft / 150 ft
VFR Approach/Landing: Forced Landing

Wreckage and Impact Information

Crew Injuries: 1 Minor
Aircraft Damage: Destroyed
Passenger Injuries: 2 Minor, 1 None
Aircraft Fire: On-Ground
Ground Injuries: N/A
Aircraft Explosion: None
Total Injuries: 3 Minor, 1 None
Latitude, Longitude: 41.555556, -93.691389

3 comments:

  1. So basically in this case the firewall protected the engine from burning down while the rest of the plane did …..

    ReplyDelete
  2. Firewalls keep fires from breaching the cabin. They do not make an aircraft fireproof after a crash, especially if tanks are leaking. And it wouldn't have mattered even if it didn't burn up. Destroyed is destroyed. Once a Cirrus' chute is deployed, it's almost always considered destroyed and an insurance write off. Only a handful have ever been repaired to flyable condition after a CAP deployment.

    ReplyDelete
    Replies
    1. Yes i know , firewalls are meant to shield the cabin from trouble up front like fire , in this case , with some imagination , you can say it was the other way around and the engine was protected from the burning cabin.
      Offcourse the firefighters saved the engine compartment in the end and not the firewall ......

      Delete