WPR21LA312

NTSB accident investigation · Lake LA-4 · Lake Isabell, CA · August 3, 2021

Accident · Minor injuriesClass 4 · LimitedFinal report
Date
August 3, 2021, 14:30 local (21:30 UTC)
Place
Lake Isabell, CA · Lake environment
Injuries
1 minor
Damage
Substantial damage
Phase of flight
Takeoff
Aircraft
N7615LLake LA-4
Defining event
Takeoff: Collision during takeoff/land
Weather
Visual (VMC) · Day
Status
Completed
Report
Approved by Office Director
Investigation class
Class 4 - Basic report with no Prelim publish
NTSB office
Western Pacific Region
Parties
Federal Aviation Administration
FAA report
20210803013389A
Case key
103673

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 pilot’s failure to establish a positive climb rate after takeoff, which resulted in an impact with an object.

Findings · 3

NTSB’s coded findings. Those marked are part of the probable cause; the rest are factors or other findings. Under each, the cases with the same finding.

Performance/control parameters: configurationAircraft › Aircraft oper/perf/capability · Incorrect use/operationLake LA-4: 1 caseAll aircraft: 80 cases
Performance/control parameters: climb rateAircraft › Aircraft oper/perf/capability · Not attained/maintainedLake LA-4: 1 caseAll aircraft: 265 casesProbable cause
Object/animal/substance: tree(s)Environmental issues › Physical environment · Effect on equipmentLake LA-4: 1 caseAll aircraft: 933 cases

Sequence of events

The events NTSB coded, in order, by phase of flight. The defining event is the one that best describes the accident. Under each, the cases with the same event anywhere in their sequence.

Analysis

The pilot of the amphibious airplane reported that, after landing on the water he taxied to a boat ramp where he drained water out of the airplane before he took off from the top of the boat ramp. Once airborne, he established a climb attitude, but the airplane was not able to maintain a climb. He further added that there was insufficient time to raise the landing gear before the airplane landed on the water. The airplane sustained substantial damage to the right wing and aft fuselage and empennage. A witness reported that he assisted the pilot in pulling the airplane out of the water and onto the boat ramp. The water was drained out of the airplane, and then the pilot commenced with the takeoff. The witness further reported that the airplane struck a tree branch before it impacted the water. Review of recorded video provided by the witness showed that the airplane departed from the top of a declining concrete boat ramp and became airborne just before the waterline at the bottom of the ramp. Throughout the takeoff sequence, the engine could be heard with no noticeable changes in sound. The video showed the airplane briefly remained airborne at a low altitude before it descended into the water. A Federal Aviation Administration inspector interviewed the pilot. The pilot reported that there were no preaccident mechanical malfunctions or failures with the airplane that would have precluded normal operation.

Aircraft

Registration
N7615L
Reported as
Lake LA-4 (388)
Category
Airplane
Serial number
388
Built
1968
Engine
Lycoming O-360-A1A, 180 horsepower, reciprocating
Damage
Substantial damage
Flight
Personal · Part 91
Airworthiness certificate
Standard, Normal
Last inspection
Annual · August 1, 2020
Departed
WHP · Pacoima, CA
Destination
Same as departure
Equipment
Stall warning system, ADS-B, Electronic flight bag or handheld device

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
61
Injuries
Minor
Certificates
Flight instructor, Remote, Commercial
Airplane ratings
Single-engine land, Single-engine sea
Instrument ratings
Airplane
Medical
BasicMed, Unknown
Last flight review
July 27, 2021
Seat
Left
Restraint
Lap only
Flight hours
1,440 total · 29 in this make and model · 1,340 as pilot in command · 90 in the last 90 days · 33 in the last 30 days

Weather

Conditions
Visual (VMC) · Day
Wind
290° at 8 knots
Visibility
7 statute miles
Lowest ceiling
None
Temperature
97 °F, dew point 45 °F
Altimeter
29.90 inHg
Observed at
KBFL, 33 nm away
METAR
KBFL 032154Z 29008KT 7SM CLR 36/07 A2990 RMK AO2 SLP118 T03610072

Docket · 6

The files NTSB released with the investigation on June 14, 2022, on NTSB’s docket system: statements, records, photos and specialists’ reports. 21.9 MB in all.

FAA reports on this event · 1

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

Other investigations on N7615L · 1

Matched to the same aircraft by N-number and date.