# NTSB FTW94FA052: Piper PA-23-160, N4382P, Franktown, CO, December 22, 1993 - Type: NTSB accident investigation - Classification: Accident · Serious injuries · Field investigation · Final report - Date: December 21, 1993, 21:18 local (Dec 22, 1993, 04:18 UTC) - Place: Franktown, CO - Coordinates: 39.380184, -104.749114 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=39.3802&lon=-104.7491&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Highest injury: Serious injuries - Injuries: 4 serious - Status: Completed, report September 13, 1994 - Report: Approved by Office Director - NTSB case key (mKey): 18875 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=FTW94FA052 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/18875/pdf - Page: https://openairdocs.org/ntsb/FTW94FA052 ## Probable cause WAS THE PILOT'S DISREGARD OF FORECAST ICING CONDITIONS AND DELAYED APPLICATION OF CARBURETOR HEAT, RESULTING IN STRUCTURAL AND INDUCTION ICING. FACTORS WERE THE ICING CONDITIONS AND UNSUITABLE TERRAIN FOR A FORCED LANDING. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - In flight encounter with weather, cruise - weather condition - icing conditions (contributing factor) - wing - ice - in-flight weather advisories - disregarded, pilot in command (cause) - Loss of engine power(partial) - nonmechanical, descent - emergency - 1 engine - weather condition - carburetor icing conditions (contributing factor) - carburetor heat - delayed, pilot in command (cause) - Forced landing, descent - emergency - In flight collision with object, descent - emergency - object - tree(s) - terrain condition - none suitable (contributing factor) ## Analysis IN CRUISE FLIGHT, ON A VFR/IFR FLIGHT PLAN, THE AIRCRAFT BEGAN TO ACCUMULATE ICE. ALTITUDE COULD NOT BE MAINTAINED AND POWER WAS REPORTEDLY LOST TO ONE ENGINE. A FORCED LANDING WAS CONDUCTED TO A WOODED AREA. WEATHER WAS IFR IN HEAVY SNOW WITH TEMPERATURE AND DEW POINT OF 21 DEGREES. BOTH ENGINES WERE EXAMINED AND NO MECHANICAL MALFUNCTIONS WERE DISCOVERED. THE PILOT STATED THAT CARBURETOR HEAT WAS APPLIED AFTER LOSING POWER TO ONE ENGINE. THE PILOT AND THE ATP RATED PASSENGER REQUESTED AND RECEIVED SEVERAL WEATHER REPORTS ON EN ROUTE AND DESTINATION CONDITIONS. THESE REPORTS FORECAST THE ENCOUNTERED CONDITIONS. ## Factual narrative HISTORY OF FLIGHT On December 21, 1993, at 2118 mountain standard time, a Piper PA-23-160, N4382P, conducted a forced landing into a heavily wooded area 3 miles east of Franktown, Colorado. The two pilots and two passengers received serious injuries and the aircraft sustained substantial damage. Instrument meteorological conditions prevailed and a VFR flight plan was filed for this personal flight from Asheville, North Carolina, to Englewood, Colorado. The flight made a fuel stop at Salina, Kansas, prior to the leg which ended with the accident, and picked up an IFR clearance when approaching the Englewood area. The pilot contacted Denver Approach Control at 2103 and was assigned an altitude of 9,000 feet above mean sea level (MSL). They were given ATIS information lima, (see meteorological portion of this document), and vectors for the ILS (instrument landing system) approach to runway 35 at Centennial Airport. At 2108, a descent to 8,000 feet was given by approach control, and at 2115, the pilot informed approach control they were picking up some ice. At 2116, the pilot informed approach control they were losing an engine and losing altitude. The last communications with the aircraft occurred at 2117. At that time, the pilot was reporting a rough running engine and an altitude of 7,000 feet with intermittent ground contact. (See attached communications transcripts and controller statements). After radar and communications were lost, an ELT (emergency locator transmitter) was picked up by Denver Center. The crew had attempted a forced landing and the aircraft collided with trees during final approach. Accident site elevation was approximately 6,000 feet MSL. According to the pilot in command, she was flying and her husband, a commercial airline pilot, was handling the radios. The pilot said, "at approximately 12-13 miles out of Centennial everything happened at once. We had begun to notice a definite drop in ground speed. Sid [the other pilot] said we were starting to get a little buildup of ice. I recall he reported this to DEN approach." The pilot further stated, "I cannot remember everything that happened. I know we lost some power. There had been no engine problems the entire trip. However, I recall a sudden loss of power and altitude. We were at cruise power and had not throttled back for a descent. I believe we lost power on one engine, but I cannot say which. I remember putting on carb heat and the aux fuel pumps. The other engine was set at full power." "We waked up both of our sons who were in the rear seats, making them check their seat belts. Everything happened so quickly - the loss of power and altitude. I remember Sid telling DEN approach we were going down. We never lost control of the airplane; there was no stall, no spin." METEOROLOGICAL INFORMATION Information lima at Centennial Airport was "indefinite ceiling five hundred sky obscured visibility one snow and fog wind zero five zero at seven altimeter three zero zero niner." Temperature and dew point at the time were 21 degrees Fahrenheit. During the flight, the crew asked for and received several weather reports concerning conditions enroute and at Centennial Airport. That weather information is attached. WRECKAGE AND IMPACT INFORMATION The aircraft came to rest in a clearing after impact with the previously mentioned trees. Both wings were separated outboard of the nacelles and both fuel tanks were compromised. A strong odor of fuel was present throughout the accident site. The right propeller was separated from the engine and both blades were bent rearward on both engines. The fuselage exhibited impact damage both forward and aft of the cabin, and all landing gear were in the up position. Tree particles were imbedded in both the fuselage and wings, and trees along the entry path were scarred and broken. The cabin interior was intact with the right yoke grips broken off. All restraints remained anchored and did not exhibit separation. Other cockpit information is contained in the attached supplements. Flight control continuity was established, and the flaps were found in the up position. When the wreckage was examined by the investigator in charge approximately one and a half hours after the accident, patches of ice were noted on the vertical stabilizer. (See attached photographs). TESTS AND RESEARCH Both engines were examined by the investigator in charge assisted by an FAA airworthiness inspector and a technical representative from the engine manufacturer. Engine continuity was established and cold compression was present on all cylinders. The spark plugs of both engines exhibited carbon buildup in a uniform pattern and the magnetos, fuel pumps, and oil pumps operated in a normal fashion. Fuel was present in both engines. ADDITIONAL INFORMATION The wreckage was released to the owner's representative on April 1, 1994. No parts were retained. ## Aircraft - Registration: [N4382P](https://openairdocs.org/deregistered/N4382P-1994-11-21), registration cancelled 1994-11-21, S/N 231890 (OpenAirDocs) - Reported make and model: PIPER PA-23-160 - Registry model: [Piper PA-23-160](https://openairdocs.org/model/piper-pa-23-160) (registry code 7102304) (OpenAirDocs) - Category: Airplane - Serial number: 23-1890 - Airframe hours: 2798 - Engines: LYCOMING O-360-A1D 180 horsepower reciprocating - Damage: Destroyed - Flight: Personal, Part 91 - Registered owner: Moran, Charles G. - Airworthiness certificate: Standard, Normal - Last inspection: Annual, February 24, 1993, 153 hours before - Departed: SLN, SALINA, KS - Destination: APA, ENGLEWOOD, CO - Flight plan: VFR/IFR ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 45; commercial, flight instructor; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 2, valid medical--no waivers/lim.; seat: left; flight hours: 930 total, 215 in this make and model, 760 as pilot in command, 141 in the last 90 days, 47 in the last 30 days, 10 in the last 24 hours ## Weather - Conditions: Instrument (IMC), Night/dark - Wind: 50° at 7 knots - Visibility: 1 statute miles - Lowest ceiling: 500 ft overcast - Temperature: 21 °F, dew point 21 °F - Altimeter: 30.00 inHg - Observed at: APA, 15 nm away ## FAA reports on this event (1) The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs). - [Accident 19931221047099A](https://openairdocs.org/incident/19931221047099A), Dec 21, 1993: Piper PA23160, Franktown, CO, Destroyed. Plane iced up en route. Lost power one engine. Unable fly. Crashed into woods. Heavy snow. Lack carb induction heat From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.