ERA25LA030

NTSB accident investigation · Zenith Zodiac 601 HDS · Altoona, PA · October 17, 2024

Accident · No injuriesClass 3 · LimitedFinal report
Date
October 17, 2024, 15:15 local (19:15 UTC)
Place
Altoona, PA · Runway 3
Injuries
1 uninjured
Damage
Substantial damage
Phase of flight
Initial climb
Aircraft
N511JGZenith Zodiac 601 HDS
Defining event
Initial climb: Fuel starvation
Weather
Visual (VMC) · Day
Status
Completed
Report
Approved by Office Director
Investigation class
Class 3
NTSB office
Eastern Region Aviation
Parties
FAA/FSDO
FAA report
20241017016379A
Case key
195410

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 total loss of engine power due to fuel starvation as a result of a deteriorated gascolator gasket. Contributing was the failure of the mechanic to replace the gasket during the most recent condition inspection.

Findings · 2

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.

Fuel system: fuel distributionAircraft › Aircraft systems · Damaged/degradedGosselin Mark J ZODIAC 601 HDS: 1 caseAll aircraft: 141 casesProbable cause
Inspection: scheduled/routine inspectionPersonnel issues › Task performance · Maintenance personnelGosselin Mark J ZODIAC 601 HDS: 1 caseAll aircraft: 167 casesProbable cause

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

Shortly after takeoff, as the airplane was climbing through 300 ft above ground level, the engine misfired, then suddenly stopped producing power. Unable to troubleshoot due to the low altitude, the pilot lowered the nose and attempted a forced landing on the remaining runway. The airplane landed hard, collapsing the landing gear and damaging the wings and airframe. Postaccident examination of the airplane did not reveal any engine anomalies; however, an examination of the fuel system revealed the fuel gascolator was installed partially outside of the engine compartment, exposing it to the air slipstream. The gascolator exhibited features consistent with a fuel leak. The gascolator bowl was not completely secure to the upper portion of the gascolator and it leaked fuel when touched by hand. The most recent engine maintenance was completed about 10 days before the accident and, although the fuel gascolator gasket was not mentioned in the logbook entry, a fuel system inspection was documented. The condition of the gasket would have warranted replacement. The gascolator bowl gasket was stiff and cracked, which likely allowed fuel to leak out during the flight, starving the engine of fuel. The circumstances of the accident are consistent with a total loss of engine power due to fuel starvation, which resulted in a loss of engine power and hard landing.

Factual narrative

On October 17, 2024, at 1515 eastern daylight time, an experimental amateur-built Zenith Zodiac 601HDS airplane, N511JG, was substantially damaged when it was involved in an accident near Altoona, Pennsylvania. The private pilot was not injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. The private pilot reported that there were no irregularities noted with the airplane during the preflight inspection, engine run-up, or taxi before departing from runway 3 at Altoona/Blair County Airport (AOO), Altoona, Pennsylvania. The pilot intended to remain in the airport traffic pattern; however, during the initial climb, when the airplane was climbing through 300 ft above ground level, the engine started to “misfire,” then immediately stopped producing power. Unable to troubleshoot due to the low altitude, the pilot lowered the nose and attempted a forced landing on the remaining runway. The airplane landed hard and the landing gear collapsed, which resulted in the wings and airframe buckling. The airplane then skidded to a stop on the side of the runway. Examination of the airplane revealed signatures to the propeller that were consistent with a lack of rotation during the impact; the engine was intact. Engine crankshaft and valvetrain continuity was established and compression was attained on each cylinder. Both magnetos produced spark at each of the posts. A subsequent examination of the fuel system revealed 10 gallons of fuel on board. In addition, the fuel gascolator was installed partially outside of the engine compartment, exposing it to the air slipstream. The gascolator exhibited features consistent with a fuel leak. The gascolator bowl was not completely secure to the upper portion of the gascolator and it would leak fuel when lightly touched by hand. The gascolator was opened and the gasket at the top of the bowl was found to be stiff and cracked. A review of maintenance records documented an annual condition inspection had been completed about 10 days before the accident. The logbook entry did not document any maintenance or inspection to the gascolator specifically, but the fuel system inspection was documented and tested, yielding no leaks.

Aircraft

Registration
N511JG
Reported as
Zenith Zodiac 601 HDS
Category
Airplane, amateur-built
Serial number
6-3331
Built
2002
Airframe hours
222
Engine
Continental C90-12F, 90 horsepower, reciprocating
Damage
Substantial damage
Flight
Personal · Part 91
Airworthiness certificate
Special, Experimental light sport (Special)
Last inspection
Condition · October 6, 2024 · 1 hours before
Destination
Same as departure
Airport
AOO · Altoona/Blair County, runway 03/21, 5,465 × 100 ft, asphalt
Equipment
ADS-B, Electronic flight bag or handheld device, Handheld GPS

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
73
Injuries
None
Certificate
Private
Airplane ratings
Single-engine land
Medical
Sport pilot, Without waivers/limitations
Last flight review
September 13, 2023
Seat
Left
Restraint
3-point
Flight hours
669 total · 334 in this make and model · 669 as pilot in command · 5.5 in the last 90 days · 1 in the last 30 days

Weather

Conditions
Visual (VMC) · Day
Wind
360° at 8 knots, gusting 17
Visibility
10 statute miles
Lowest ceiling
None
Temperature
61 °F, dew point 30 °F
Altimeter
30.26 inHg
Observed at
AOO
METAR
KAOO 171853Z AUTO 36008G17KT 10SM CLR 16/M01 A3026 RMK AO2 SLP253 T01561006

Docket · 5

The files NTSB released with the investigation on April 2, 2025, on NTSB’s docket system: statements, records, photos and specialists’ reports. 28.2 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.