ERA14LA103

NTSB accident investigation · Piper PA-12 · Zephyrhills, FL · January 18, 2014

Accident · No injuriesLimited investigationFinal report
Date
January 18, 2014, 12:00 local (17:00 UTC)
Place
Zephyrhills, FL
Injuries
2 uninjured
Damage
Substantial damage
Phase of flight
Landing
Aircraft
N3668NPiper PA-12
Defining event
Landing-flare/touchdown: Hard landing
Weather
Visual (VMC) · Day
Status
Completed · report September 24, 2014
Report
Approved by Office Director
NTSB office
Eastern Region Aviation
FAA report
20140118000519A
Case key
88710

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 inadequate compensation for gusting wind conditions, which resulted in a hard landing that produced forces beyond the structural capability of the airframe.

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: landing flareAircraft › Aircraft oper/perf/capability · Not attained/maintainedPiper PA-12: 5 casesAll aircraft: 1,285 casesProbable cause
Use of equip/info: aircraft controlPersonnel issues › Task performance · PilotPiper PA-12: 51 casesAll aircraft: 9,295 casesProbable cause
Wind: gustsEnvironmental issues › Conditions/weather/phenomena · Contributed to outcomePiper PA-12: 7 casesAll aircraft: 1,199 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 reported that he was landing on runway 4 with surface wind from 275 degrees at 15 knots gusting to 25 knots. The approach was normal, but the airplane touched down long. A gust of wind lifted the left wing high while the pilot input full left aileron controls. He added power while attempting to recover, but the left wing descended, and the left main landing gear subsequently collapsed when the airplane landed hard, which resulted in structural damage to the lower fuselage. The airplane ground looped around the failed gear and came to a stop. The pilot reported that the main gear safety cable, which was designed to prevent airframe damage in the event of a failed main gear bungee, had malfunctioned. A postaccident examination of the braided steel cable revealed that it failed in tension overload, and no evidence of a preimpact anomaly was found. The cable attachment points were secure. The main landing gear bungees were severed. Although the position of the cable before the hard landing could not be determined due to airplane and landing gear damage, the safety cable likely severed the main landing gear bungees during the accident sequence.

Factual narrative

On January 18, 2014, about 1200 eastern standard time, a Piper PA-12, N3668N, was substantially damaged following a hard landing at Zephyrhills Municipal Airport (ZPH), Zephyrhills, Florida. The private pilot and one passenger were not injured. The airplane was operated by the pilot under the provisions of 14 Code of Federal Regulations Part 91 as a personal flight. Day, visual meteorological conditions prevailed for the flight, and no flight plan was filed. The flight originated from Tampa North Aero Park (X39), Tampa, Florida, about 1130. The pilot reported that he was number two of a formation flight of two and was landing on runway 4. He reported surface winds at the time to be from 275 degrees at 15 knots with gusts to 25 knots. The approach to landing was normal and the airplane touched down "a little long past the numbers due to the tailwind." A gust of wind then lifted the left wing high while he already had full left aileron controls in. He added power while attempting to recover, the left wing descended, and the left main landing gear collapsed as the airplane landed hard. The airplane ground looped around the failed gear and came to a stop. An inspector with the Federal Aviation Administration responded to the accident site and inspected the wreckage. He reported that the left main gear collapsed, resulting in structural damage to the lower fuselage. Structural damage was also observed on the left wing. The pilot reported that the main gear safety cable "failed" and cut the landing gear bungees during the hard landing. The safety cable was subsequently removed by the pilot and was forwarded to the NTSB Investigator-in-Charge for further examination. The braided steel cable was about 19 inches in length and was fitted with attachment hardware on each end. The failure point was approximately 12 inches from one end (or 7 inches from the opposite end). The failed ends exhibited a "broomstraw" appearance, consistent with tension overload. Inside the strands on one failed end were light-colored fibers that were consistent in appearance with the landing gear bungee material. The purpose of the landing gear safety cable was to prevent airframe damage in the event of a failure of the landing gear bungee(s). Due to the landing gear and airframe damage, the position of the landing gear safety cable prior to the hard landing could not be determined.

Aircraft

Registration
N3668N
Reported as
Piper PA-12
Category
Airplane
Serial number
12-1919
Built
1947
Airframe hours
1,282
Engine
Lycoming O-320 Series, 150 horsepower, reciprocating
Damage
Substantial damage
Flight
Personal · Part 91
Operator
Connors Sean P
Registered owner
Connors Sean P
Airworthiness certificate
Standard, Normal
Last inspection
Annual · February 18, 2013
Departed
X39 · Tampa, FL
Destination
ZPH · Zephyrhills, FL
Airport
ZPH · Zephyrhills Muni, runway 04, 4,999 × 100 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
53
Injuries
None
Certificate
Private
Airplane ratings
Single-engine land
Medical
Class 3, With waivers/limitations
Last flight review
May 23, 2013
Seat
Front
Restraint
3-point
Flight hours
441 total · 295 in this make and model · 441 as pilot in command · 33 in the last 90 days · 14 in the last 30 days · 1 in the last 24 hours

Weather

Conditions
Visual (VMC) · Day
Wind
340° at 10 knots, gusting 19
Visibility
10 statute miles
Lowest ceiling
None
Temperature
54 °F, dew point 9 °F
Altimeter
30.26 inHg
Observed at
ZPH

Docket · 10

The files NTSB released with the investigation on May 27, 2014, on NTSB’s docket system: statements, records, photos and specialists’ reports. 5.8 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.