SEA94LA231

NTSB accident investigation · Cessna 172G · Paradise, WA · September 5, 1994

Accident · Serious injuriesLimited investigationFinal report
Date
September 5, 1994, 15:10 local (22:10 UTC)
Place
Paradise, WA
Injuries
1 serious, 3 minor
Damage
Destroyed
Phase of flight
Enroute
Aircraft
N4628LCessna 172G
Weather
Visual (VMC) · Day
Status
Completed · report September 24, 1995
Report
Approved by Office Director
FAA report
19940905025349A
Case key
42016

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 NTSB’s determination of the probable cause, and any contributing factors.

Proper altitude was not maintained and improper inflight planning/decision. Factors to the accident were mountainous/hilly terrain conditions and lack of total experience.

Analysis

The newly rated private pilot stated that the airplane was unable to maintain sufficient altitude to cross a ridge. However, passengers and witnesses stated the pilot maintained very low altitude throughout the flight. Passengers reported the pilot turned the airplane into a mountainous drainage where the airplane struck trees, then impacted terrain. The gradient of the terrain was determined to exceed the climb gradient capability of the aircraft.

Factual narrative

The factual narrative643 words

On September 5, 1994, approximately 1510 hours Pacific daylight time (pdt), a Cessna 172G, N4628L, registered to Cloud Dodgers Flying Club, Inc., and being flown by Dwight L. Youngquist, a recently certificated private pilot, was destroyed during collision with trees/terrain while climbing eastbound in a drainage approximately one mile south of Chinook Pass, near Paradise, Washington. The accident took place within Rainier National Park. The pilot and two passengers sustained minor injuries and a fourth occupant was seriously injured. Visual meteorological conditions existed at the time, and no flight plan had been filed. The flight, which was personal in nature, was to have been operated under 14CFR91, and originated from Packwood, Washington, with a destination of Paine Field in Everett, Washington.

A witness reported seeing the aircraft depart the Packwood Airport, located 17 nautical miles south of the accident site. The departure was approximately 1445 and the aircraft was observed to fly northbound.

A hiker in the Tatoosh Mountains just south of Rainier Park reported observing a blue and white aircraft flying northbound from the direction of Packwood and toward the Park. The hiker, who observed the aircraft from an elevation of approximately 5000 feet, estimated the aircraft's altitude to be approximately 4000 feet. A diagram of the aircraft's ground track drawn by the hiker on a topographic map indicates that the aircraft would have to maintain a minimum altitude of 4200 to 4400 feet along the depicted ground track to avoid impacting terrain. The time of this hiker's observation was approximately 1500.

Another hiker located on the south side of Naches Peak and approximately one mile north of the accident site witnessed the accident. He stated the aircraft was well below his elevation of approximately 5800 feet elevation and was climbing up the drainage eastbound when it flew into trees in a wings level attitude at low speed. He also reported that the sound of the engine was smooth and uninterrupted with no sound of surging or misfiring.

The pilot stated in his report of the accident that the aircraft was "unable to maintain sufficient altitude to cross (the) ridge ahead." However, two of the passengers stated that the pilot maintained very low altitude above the terrain throughout the flight. One of the passengers estimated the pilot's level-off altitude after takeoff from Packwood as "probably less than a thousand feet (above) the ground". These two passengers also stated that the pilot videotaped ground scenery during the flight.

The passengers stated that while flying north up the valley along the road leading from Packwood, the pilot turned right (eastward) into Dewey Creek valley where the aircraft struck trees, then impacted the ground. The direction of flight at the time of the impact was estimated to be approximately 130 degrees magnetic, based on measurements from initial tree impact damage to the main wreckage site. The passengers also reported that the stall warning horn sounded several times just before the initial impact with the trees. The aircraft impacted approximately 5100 feet above sea level, about 150 feet below the 5250 foot maximum saddle elevation over the Dewey Creek valley.

Based on reported passenger and fuel loading, the aircraft was at an estimated gross weight of 2100 pounds at the time of the accident. Its maximum certificated gross weight in the normal category is 2300 lbs. At 2100 lb gross weight and accident site density altitude of 6500 feet (estimated from Yakima weather observation), performance charts in the 1966 Cessna 172G owner's manual indicate the aircraft would have an approximate maximum climb rate of 470 feet per minute at a best rate-of-climb airspeed of 76 mph (equivalent to a climb capability of 371 feet per statute mile) with mixture leaned for best power. As measured on a topographic map of the area, terrain at the impact site slopes upward at over 1000 feet per statute mile.

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 collision with terrain/waterClimb
Terrain condition - mountainous/hillyFactor
Proper altitude - not maintainedPilot in commandCause
Lack of total experiencePilot in commandFactor
In-flight planning/decision - improperPilot in commandCause

Aircraft

Registration
N4628L
Reported as
Cessna 172G
Category
Airplane
Serial number
172-54623
Airframe hours
6,380
Engine
Continental O-300-D, 145 horsepower, reciprocating
Damage
Destroyed
Flight
Personal · Part 91
Registered owner
Cloud Dodgers Flying Club
Airworthiness certificate
Standard, Utility; Standard, Normal
Last inspection
Annual · June 24, 1994 · 68 hours before
Departed
55S · Packwood, WA
Destination
PAE · Everett, WA

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
36
Certificate
Private
Airplane ratings
Single-engine land
Medical
Class 3, Valid Medical--w/ waivers/lim
Seat
Left
Flight hours
78 total · 56 in this make and model · 31 as pilot in command · 18 in the last 90 days · 4 in the last 30 days · 2 in the last 24 hours

Weather

Conditions
Visual (VMC) · Day
Wind
70° at 4 knots
Visibility
60 statute miles
Lowest ceiling
None
Temperature
81 °F, dew point 46 °F
Altimeter
30.00 inHg
Observed at
YKM, 43 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.