In-flight engine shutdown.

Attributes
ACN	299060
Time
Date	199503
Day	Sat
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : hbu airport : guc
State Reference	CO
Altitude	msl bound lower : 17000 msl bound upper : 17000
Environment
Flight Conditions	IMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zdv
Operator	general aviation : personal
Make Model Name	PA-23-250 Aztec
Operating Under FAR Part	Part 91
Flight Phase	cruise other other other
Route In Use	enroute : on vectors enroute airway : zdv
Flight Plan	IFR
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : instrument pilot : private
Experience	flight time last 90 days : 38 flight time total : 280 flight time type : 38
ASRS Report	299060
Person 2
Affiliation	government : faa
Function	controller : radar
Qualification	controller : radar
Events
Anomaly	aircraft equipment problem : critical inflight encounter : weather other anomaly other
Independent Detector	aircraft equipment other aircraft equipment : unspecified other flight crewa
Resolutory Action	controller : provided flight assist flight crew : declared emergency none taken : unable other
Consequence	Other
Supplementary
Primary Problem	Weather

Narrative:

While in turbulent IMC conditions at 17000 ft MSL on IFR flight plan from smo to apa on mar/sat/95, lost power on right engine. Conditions at the time of stoppage were: IMC conditions, turbulent (moderate) air, moderate to heavy mixed ice. Notified ZDV and received radar vectors to the nearest airport, gvd. I secured the right engine and selected alternate air for the left engine (alternate air is supposedly automatic). Attempted restart of right engine on alternate air. Starter solenoid wouldn't engage. Stabilized the aircraft and made gradual descent to about 14000 ft where I broke out of the clouds. Aircraft was carrying a significant amount of ice on the wings. Pitot heat, windshield heat, propeller heat and defroster were full on pitot system frozen - no airspeed (indicator acted as altimeter). Made visual acquisition of guc canceled IFR flight plan with ZDV. Established 2 way radio communication with gunisson CTAF. Attempted to lower landing gear - did not get down and locked indication until just before threshold. Made a high and fast approach to runway 24 single engine approach, unusable airspeed indicator, uncertain gear indication. Landed successfully and without further incident. This incident occurred because I deviated from my filed flight plan by accepting a ZDV vector for direct to the larks 1 STAR. By accepting this offer, I flew over mountainous terrain into known IMC conditions. After determining the severity of the WX, I continued further into the condition rather than doing a 180 degree turn or asking for a deviation. ZDV was aware of turbulence and had given me an altitude block of 17000-18000 ft to accommodate the turbulence and ice. Callback conversation with reporter revealed the following information: the reporter states that the aztec has an automatic alternate air door that failed to close. This allowed the engine induction system to ice up, choking the engine. It ran perfectly the next day. The starter is an ongoing problem with this particular engine. The starter motor turns properly. The reporter realizes how lucky he was.

Original NASA ASRS Text

Title: INFLT ENG SHUTDOWN.

Narrative: WHILE IN TURBULENT IMC CONDITIONS AT 17000 FT MSL ON IFR FLT PLAN FROM SMO TO APA ON MAR/SAT/95, LOST PWR ON R ENG. CONDITIONS AT THE TIME OF STOPPAGE WERE: IMC CONDITIONS, TURBULENT (MODERATE) AIR, MODERATE TO HVY MIXED ICE. NOTIFIED ZDV AND RECEIVED RADAR VECTORS TO THE NEAREST ARPT, GVD. I SECURED THE R ENG AND SELECTED ALTERNATE AIR FOR THE L ENG (ALTERNATE AIR IS SUPPOSEDLY AUTOMATIC). ATTEMPTED RESTART OF R ENG ON ALTERNATE AIR. STARTER SOLENOID WOULDN'T ENGAGE. STABILIZED THE ACFT AND MADE GRADUAL DSCNT TO ABOUT 14000 FT WHERE I BROKE OUT OF THE CLOUDS. ACFT WAS CARRYING A SIGNIFICANT AMOUNT OF ICE ON THE WINGS. PITOT HEAT, WINDSHIELD HEAT, PROP HEAT AND DEFROSTER WERE FULL ON PITOT SYS FROZEN - NO AIRSPD (INDICATOR ACTED AS ALTIMETER). MADE VISUAL ACQUISITION OF GUC CANCELED IFR FLT PLAN WITH ZDV. ESTABLISHED 2 WAY RADIO COM WITH GUNISSON CTAF. ATTEMPTED TO LOWER LNDG GEAR - DID NOT GET DOWN AND LOCKED INDICATION UNTIL JUST BEFORE THRESHOLD. MADE A HIGH AND FAST APCH TO RWY 24 SINGLE ENG APCH, UNUSABLE AIRSPD INDICATOR, UNCERTAIN GEAR INDICATION. LANDED SUCCESSFULLY AND WITHOUT FURTHER INCIDENT. THIS INCIDENT OCCURRED BECAUSE I DEVIATED FROM MY FILED FLT PLAN BY ACCEPTING A ZDV VECTOR FOR DIRECT TO THE LARKS 1 STAR. BY ACCEPTING THIS OFFER, I FLEW OVER MOUNTAINOUS TERRAIN INTO KNOWN IMC CONDITIONS. AFTER DETERMINING THE SEVERITY OF THE WX, I CONTINUED FURTHER INTO THE CONDITION RATHER THAN DOING A 180 DEG TURN OR ASKING FOR A DEV. ZDV WAS AWARE OF TURB AND HAD GIVEN ME AN ALT BLOCK OF 17000-18000 FT TO ACCOMMODATE THE TURB AND ICE. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATES THAT THE AZTEC HAS AN AUTOMATIC ALTERNATE AIR DOOR THAT FAILED TO CLOSE. THIS ALLOWED THE ENG INDUCTION SYS TO ICE UP, CHOKING THE ENG. IT RAN PERFECTLY THE NEXT DAY. THE STARTER IS AN ONGOING PROB WITH THIS PARTICULAR ENG. THE STARTER MOTOR TURNS PROPERLY. THE RPTR REALIZES HOW LUCKY HE WAS.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.