LAX06FA131

NTSB accident investigation · Cessna 208B · Oak Glen, CA · March 29, 2006

Accident · FatalField investigationFinal report
Date
March 28, 2006, 16:55 local (Mar 29, 2006, 00:55 UTC)
Place
Oak Glen, CA
Injuries
2 fatal
Damage
Destroyed
Phase of flight
Enroute
Aircraft
N208WECessna 208B
Weather
Instrument (IMC) · Day
Status
Completed · report May 28, 2008
Report
Approved by Office Director
Parties
Federal Aviation Administration, Pratt & Whitney Canada, Cessna Aircraft Company
FAA report
20060328005389A
Case key
63410

From the NTSB’s public API. By law, NTSB reports can’t be used as evidence in lawsuits over the accident.

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Probable cause

The pilot's continued flight into instrument meteorological weather conditions and his subsequent failure to maintain an adequate airspeed while maneuvering, that led to a stall/spin.

Sequence of events

NTSB’s coding before 2008: each occurrence and phase of flight, and the causes and factors under it. The codes are defined in NTSB’s coding manual.

In flight encounter with weatherClimb - to cruise
Weather condition - drizzle/mist
Weather condition - clouds
Weather condition - obscuration
Flight into known adverse weather - continuedPilot in commandCause
Terrain condition - mountainous/hilly
Loss of control - in flightManeuvering - turn to reverse direction
Airspeed - not maintainedPilot in commandCause
Stall/spin - encounteredPilot in commandCause
In flight collision with terrain/waterDescent - uncontrolled
Terrain condition - mountainous/hilly

Analysis

The airplane was operated by the manufacturer and was on a sales demonstration itinerary. On the accident flight the airplane was being repositioned following a demonstration and the two pilots included a commercially licensed manufacturer's sales pilot and a private licensed regional sales distributor. One of the two pilots onboard requested, and received, an abbreviated weather briefing prior to departure, the details of which included an airman's meteorological information notice (AIRMET) for occasional moderate rime ice. He then filed an instrument flight rules flight plan for a route passing over mountainous terrain, with a published Minimum En route Altitude (MEA) for the airway that was above the predicted icing level. The flight plan was not activated and the pilots told a TRACON controller who was providing VFR advisories that they intended to continue under visual flight rules through a mountain pass and open their IFR flight plan after reaching the other side of the pass where the MEA was lower. A review of the mode C reported altitudes flown by the pilots and an analysis of the cloud bases and tops revealed that the flight was likely in at least intermittent, if not mostly solid, instrument meteorological conditions as it flew through the pass. As the flight approached the other end of the pass, the controller advised the pilots that the radar showed they were heading into rising terrain. The controller asked, "Do you have the terrain in sight?" One of the pilots responded, "we're maneuvering away from the terrain right now." After that, radar contact was lost. Recorded radar data showed that the airplane made a right-hand turn toward rising terrain while continuing to climb to an approximate altitude of 8,800 feet mean sea level (msl). The last minute of radar data showed the airplane at altitudes of 8,000 feet msl, 8,800 feet msl, and 8,600 feet msl. The last radar return was at an altitude of 7,300 feet msl. An aircraft performance study was accomplished using recorded radar data and aerodynamic data provided by Cessna. Based on the radar data and other relevant information, as the aircraft turned toward the rising terrain, the bank angle steadily increased, until a very abrupt change in pitch consistent with a stall occurred, and the airplane departed controlled flight and descended at a very steep nose down attitude into the mountainous terrain. The airplane wreckage was subsequently located at an elevation of 6,073 feet. Nearby ground witnesses first noticed the sound of the airplane, that then suddenly changed to a high-pitched increasing rpm. Witnesses then saw the accident airplane coming out of the clouds almost straight nose down. The witnesses described the weather as cold with drizzling rain and reduced visibility due to the clouds. Examination of the wreckage revealed no evidence of mechanical malfunction or failure.

Factual narrative

History of flight

On March 28, 2006, about 1655 Pacific standard time, a Cessna 208B, N208WE, departed controlled flight and descended into mountainous terrain while maneuvering near Oak Glen, California. Cessna Aircraft Company was operating the airplane under the provisions of 14 Code of Federal Regulations Part 91. Both the commercial pilot and private pilot on board were killed. The airplane was destroyed. The cross-country business flight departed Jacqueline Cochran Regional Airport (TRM), Thermal, California, about 1635, with a planned destination of Ontario International Airport (ONT), Ontario, California. Instrument meteorological conditions (IMC) prevailed, and an instrument flight rules (IFR) flight plan had been filed; however, the flight plan had not been activated.

Cessna Aircraft Company owned and operated the accident airplane, which was being piloted by an independent regional aircraft sales distributor/pilot (RSD) and a Cessna Caravan Sales Manager/pilot (CSM). The CSM pilot, flying the accident airplane, departed Wichita, Kansas, on March 27, 2006. The purpose of the trip was to market the airplane to prospective customers. The CSM pilot flew the airplane to North Las Vegas, Nevada, where he met with the RSD pilot.

After staying overnight in North Las Vegas, both pilots flew to Kingman, Arizona, then on to Thermal (TRM). In the area of TRM, the two pilots conducted a demonstration flight for a prospective customer. The demonstration flight lasted about 1 hour. After the demonstration flight, and prior to departing TRM, the airplane was serviced with 100 gallons of Jet-A fuel. The CSM pilot requested and received an abbreviated weather briefing from the Riverside Flight Service Station, which included an airman's meteorological information notice (AIRMET) for occasional moderate rime ice. He then filed an IFR flight plan from TRM to ONT via Airway V388 through the 'DEWAY' intersection and to the Paradise (PDZ) VOR, with a planned en route altitude of 10,000 feet.

The CSM pilot listed himself as the pilot-in-command. Witnesses at TRM saw the CSM pilot get into the right front seat of the airplane and the RSD pilot seat himself in the left front seat. The airplane took off in visual meteorological conditions and subsequently received VFR (Visual Flight Rules) flight following. The filed IFR flight plan was not activated.

At 1636:03, the crew received a transponder code (4711) from the Palm Springs Approach Control, and one of the pilots replied by stating, "400 feet off of thermal, ah VFR through the pass and then it's gonna be, ah I'd like to pick up a IFR after the pass to Ontario."

At 1649:52, Palm Springs Approach Control handed the flight off to Southern California Terminal Radar Approach Control TRACON (SCT). During the handoff, the Palm Springs controller told the crew that SCT was aware of their request to pickup an IFR clearance to Ontario after the pass.

At 1651:50, just after passing the 'DEWAY' intersection, radar data shows the airplane at a point north of Banning Airport (BAN), Banning, California, approximately 7 nm east of the boundary line for the SCT class "E" airspace, and making a right turn on a west/northwest track heading toward the rising terrain of the San Bernardino mountain range.

At 1654:03, radar return data shows the airplane continuing a climb, crossing 7,900 feet mean sea level (msl) and beginning a more aggressive turn, to the right, toward rising terrain.

At 1653:44 and 1654:16, the crew makes two identical calls to SCT, "So Cal Approach caravan two zero eight whiskey echo." The radar return data shows the airplane at this point in a climb starting at 7,300 feet msl and still heading towards rising terrain.

At 1654:48, SCT gave the crew an altimeter setting "29.86" and asked them to ident. After the ident, the SCT controller said, "November two zero eight whiskey echo, you're turning north into higher terrain uh, you're radar contact ten miles uh, north of Banning, mode C indicates eight thousand five hundred, do you have uh the terrain in sight sir?"

The pilot did not answer the question, but instead, at 1655:03, the pilot replied, "Uh, eight whisky echo, we're uh, maneuvering away from the terrain right now."

At 1655:07, the controller said "Roger uh, continue on a southwesterly heading please, radar contact." There was no other communication heard from the mishap airplane.

At 1655:18, the controller noticed the flight had disappeared off ATC radar and made two calls to the mishap airplane stating that radar contact was lost. According to the ATC radar track, the last location of the airplane was approximately 1 nm south of the 8,900-foot San Bernardino mountain range.

At a point north of BAN, recorded radar data showed that the airplane made a right-hand turn toward rising terrain while continuing to climb to an approximate altitude of 8,800 feet msl. The last minute of radar data showed the airplane at mode C reported altitudes of 8,000 feet msl at 1654:01; 8,800 feet msl at 1655:03; and 8,600 feet msl at 1655:08. The last radar return was at 1655:12, at a mode C reported altitude of 7,300 feet msl.

At the time of the accident, three residents at the Oak Glen Conservation Camp reported that while walking to the dining hall, they heard the sound of an aircraft overhead. They said they could not see it because the clouds were too low. The Oak Glen Conservation Camp is based in the San Bernardino National Forest at an elevation of 5,500 feet. When they first noticed the sound of the aircraft, two of the witnesses described the sound as similar to a "fluid starved power steering pump - whining." The other witness described the sound as a continuous "real, real, real" sound. According to a Cessna representative, these sounds are consistent with the sound the accident airplane would make in a cruise climb. While the witnesses were commenting amongst themselves about what they had heard, the sound suddenly changed to a high-pitched rpm (revolutions per minute) sound that continued to increase in pitch. All three witnesses looked up to the right and saw the accident airplane coming out of the clouds almost straight down. The witnesses also described the weather as cold and drizzling rain, with reduced visibility due to the clouds. Within minutes after the accident, the witnesses said that the weather worsened and it started to sleet and snow.

Search and rescue personnel were notified, but before they could locate the accident site, the weather deteriorated in the intended search area. The search was suspended until the following morning.

Los Angeles Air Route Traffic Control Center (ZLA ARTCC) issued an alert notice (ALNOT) at 1937 on March 28, 2006. There was no Emergency Locator Transmitter (ELT) signal reported. The airplane wreckage was subsequently located the following morning about 0920 by personnel from the San Bernardino County Sheriff's Department search and rescue team. The wreckage was located about 3/4-mile north of the Oak Glen Conservation Camp. The elevation at the accident site was 6,073 feet.

Personnel information

LEFT SEAT PILOT-RSD Pilot

A review of Federal Aviation Administration (FAA) airman records revealed that the RSD pilot held a private pilot certificate with ratings for airplane single engine land, and instrument airplane.

The pilot, age 45, held a third-class medical certificate issued on July 19, 2005. It had no limitations or waivers.

No personal flight records were located for the pilot. The IIC obtained the aeronautical experience listed in this report from a review of the FAA airmen medical records on file in the Airman and Medical Records Center located in Oklahoma City. The pilot reported on his medical application that he had a total time of 2,300 hours.

RIGHT SEAT PILOT-CSM Pilot

A review of FAA airman records revealed that the CSM pilot held a commercial

Aircraft

Registration
N208WE
Reported as
Cessna 208B
Category
Airplane
Serial number
208B1171
Airframe hours
52
Engine
Pratt & Whitney Canada PT6A-114A, 675 horsepower, turbo prop
Damage
Destroyed
Flight
Business · Part 91
Registered owner
Cessna Aircraft Company
Airworthiness certificate
Standard, Normal
Last inspection
Annual · January 1, 2006 · 50.4 hours before
Departed
TRM · Thermal, CA
Destination
ONT · Ontario, CA
Flight plan
IFR

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 · 2

As NTSB recorded them. NTSB leaves out names.

Role
Pilot
Age
53
Injuries
Fatal
Certificate
Private
Airplane ratings
Single-engine land
Instrument ratings
Airplane
Medical
Class 3, Without waivers/limitations
Last flight review
April 1, 2005
Seat
Left
Toxicology
Performed
Flight hours
2,300 total
Role
Co-pilot
Age
45
Injuries
Fatal
Certificate
Commercial
Airplane ratings
Single-engine land, Single-engine sea, Multi-engine land
Instrument ratings
Airplane
Medical
Class 1, With waivers/limitations
Last flight review
September 1, 2004
Seat
Right
Toxicology
Performed
Flight hours
1,792 total · 740 in this make and model

Weather

Conditions
Instrument (IMC) · Day
Wind
170° at 8 knots
Visibility
20 statute miles
Lowest ceiling
2,300 ft broken
Temperature
54 °F, dew point 41 °F
Altimeter
29.87 inHg
Observed at
RIV, 20 nm away

Docket · 26

The files NTSB released with the investigation on May 19, 2008, on NTSB’s docket system: statements, records, photos and specialists’ reports. 28.3 MB in all.

Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1Item 1 · .PDF · 554 KBMeteorology 5 - Factual Report of Weather SpecialistItem 2 · .PDF · 3.3 MBNTSB Aircraft Performance ReportItem 3 · .PDF · 717 KBWitness Statement- Bill ButtsItem 4 · .PDF · 143 KBWitness Statement- Ryland DeckerItem 5 · .PDF · 75 KBWitness Statement- GarrisonItem 6 · .PDF · 18 KBWreckage DiagramItem 7 · .PDF · 255 KBPhoto 1 - Aerial of Main Wreckage 1Item 8 · .PDF · 857 KBPhoto 2 - Aerial of Main Wreckage 2Item 9 · .PDF · 905 KBPhoto 3 - Ground View of Main WreckageItem 10 · .PDF · 874 KBPhoto 4 - Ground View of Damaged TreesItem 11 · .PDF · 820 KBPhoto 5 - Aft Floor SectionItem 12 · .PDF · 2.2 MBPhoto 6 - Engine Compressor SectionItem 13 · .PDF · 2.2 MBPhoto 7 - PropellerItem 14 · .PDF · 1.7 MBPhoto 8 - Airplane Instrument Panel Pre-AccidentItem 15 · .PDF · 1.7 MBATC(RAL FSS)-Pilot Briefing TranscriptItem 16 · .PDF · 1.9 MBATC Report (SCT)Item 17 · .PDF · 1.1 MBFinal Party Report-HoneywellItem 18 · .PDF · 4.5 MBToxicological Report- O'NeillItem 19 · .PDF · 58 KBToxicological Report- VoorhisItem 20 · .PDF · 58 KBStatement of Party Representatives to NTSB InvestigationItem 21 · .PDF · 196 KBStatement of Party Representatives to NTSB Investigation- HoneywellItem 22 · .PDF · 138 KBRelease of Aircraft Wreckage, NTSB Form 6120.15Item 23 · .PDF · 96 KBN208WE Weight & BalanceItem 24 · .PDF · 3.1 MBFuel Receipts from Thermal FBOItem 25 · .PDF · 55 KBPilot Logbook- O'NeillItem 26 · .PDF · 723 KB

FAA reports on this event · 1

The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.