DEN04FA064

NTSB accident investigation · Cessna 150H · Boulder, CO · April 18, 2004

Accident · Minor injuriesField investigationFinal report
Date
April 17, 2004, 19:30 local (Apr 18, 2004, 01:30 UTC)
Place
Boulder, CO
Injuries
1 minor
Damage
Substantial damage
Phase of flight
Initial climb
Aircraft
N105DPCessna 150H
Weather
Visual (VMC) · Day
Status
Completed · report October 28, 2004
Report
Approved by Office Director
Parties
Federal Aviation Administration
FAA report
20040417007049A
Case key
59085

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 failed magneto and the lack of suitable terrain (lake) for a forced landing.

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.

Loss of engine power(total) - mech failure/malfTakeoff - initial climb
Ignition system,magneto - failure,totalCause
Ignition system,magneto - corroded
Forced landingEmergency descent/landing
DitchingEmergency landing
Terrain condition - waterFactor

Analysis

The pilot said he was approximately 300 feet in the air on departure when the engine began to run rough. The pilot said he "put a little mixture in [and] the engine started to run fine for about 5 seconds. Then the engine died." The pilot said the only place he could land was the lake. He said that as he touched down the airplane "skimmed for a few seconds and then it went over on its back." The pilot said he got out through the windscreen, got on top of the bottom of the wing, and then swam to shore. He said the airplane sank nose first about 30 seconds later. Later examination of the airplane showed substantial damage to the left wing. The airplane's engine was examined and showed the left magneto inoperative. An internal examination of the magneto showed corrosion around the points, the P-lead, and the capacitor.

Factual narrative

History of flight

On April 17, 2004, at 1930 mountain daylight time, a Cessna 150H, N105DP, piloted by a private pilot, was substantially damaged during a forced landing into a lake, 1/2 mile east of the Boulder Municipal Airport (1V5), Boulder, Colorado. Visual meteorological conditions prevailed at the time of the accident. The personal flight was being conducted under the provisions of Title 14 CFR Part 91 without a flight plan. The pilot reported minor injuries. The local flight originated at approximately 1915.

The pilot said that he had just completed his third touch-and-go landing. He was approximately 300 feet in the air when his engine began to run rough. The pilot said he "put a little mixture in [and] the engine started to run fine for about 5 seconds. Then the engine died." The pilot said the only place he could land was the lake. He said that as he touched down, the airplane "skimmed for a few seconds and then it went over on its back." The pilot said he got out through the windscreen, got on top of the bottom of the wing, and then swam to shore. He said the airplane sank nose first about 30 seconds later.

Personnel information

The pilot, age 17, held a private pilot certificate with airplane single-engine land rating. The certificate was dated September 7, 2003.

The pilot had a third class medical, dated July 23, 2002. The medical certificate cited no limitations.

The pilot reported having 350 total flying hours, 180 in single-engine land airplanes, and 8 hours in the accident airplane.

Aircraft information

The airplane, serial number 150-68960 was a 1968 Cessna 150H. The airplane was used for pilot training and personal pleasure flying.

According to the airframe logbook, the airplane underwent an annual inspection on November 1, 2003. At the time of the inspection the airplane logbook showed a recorded tachometer time of 9,988.72 total hours. A previous entry on March 3, 2003, reflecting an engine oil change showed a tachometer time of 9,200.16 hours. The tachometer time recorded at the accident site was 9,394.74 hours.

Wreckage and impact information

The accident site was located at the center of a pond located approximately 3,000 feet east of the departure end of 1V5 runway 8R.

The airplane was predominately intact and rested upright on its landing gear submerged in approximately 15 feet of water. The airplane's right wing leading edge, from mid span outboard to the wing tip, was crushed aft to the forward spar. The left wing forward spar was bent downward. The airplane's forward windscreen was broken out and fragmented. The remainder of the airplane was undamaged.

On April 19, 2004, the airplane was retrieved from the bottom of the pond. Flight control continuity was confirmed. The airplane was retained for further testing.

Tests and research

The airplane's engine was examined at Greeley, Colorado, on May 7, 2004. The examination showed that the left magneto was not functional. No other anomalies were found. Later, an internal examination of the magneto showed corrosion around the points, the P-lead, and the capacitor.

Additional information

A party to the investigation was the FAA Flight Standards District Office, Denver, Colorado.

The airplane wreckage was released to the owner's insurance company.

Aircraft

Registration
N105DP
Reported as
Cessna 150H
Category
Airplane
Serial number
150-68960
Airframe hours
9,394.74
Engine
Continental O-200A, 100 horsepower, reciprocating
Damage
Substantial damage
Flight
Personal · Part 91
Registered owner
David Elliott
Airworthiness certificate
Standard, Normal
Last inspection
Annual · November 1, 2003 · 6 hours before
Departed
1V5 · Boulder, CO
Destination
1V5 · Boulder, CO
Airport
1V5 · Boulder Municipal Airport, runway 8R, 4,100 × 75 ft, asphalt

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
17
Injuries
Minor
Certificate
Private
Airplane ratings
Single-engine land
Medical
Class 3
Last flight review
September 7, 2003
Seat
Left
Flight hours
350 total · 8 in this make and model

Weather

Conditions
Visual (VMC) · Day
Wind
310° at 4 knots
Visibility
30 statute miles
Lowest ceiling
None
Temperature
66 °F, dew point 21 °F
Altimeter
29.69 inHg
Observed at
BJC, 10 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.