GAA16CA431

NTSB accident investigation · Cessna 152 · Hillsboro, OR · August 12, 2016

Accident · No injuriesData collectionFinal report
Date
August 12, 2016, 14:30 local (21:30 UTC)
Place
Hillsboro, OR
Injuries
1 uninjured
Damage
Substantial damage
Phase of flight
Landing
Aircraft
N48440Cessna 152
Defining event
Landing-flare/touchdown: Abnormal runway contact
Weather
Visual (VMC) · Day
Status
Completed · report December 5, 2016
Report
Approved by Office Director
NTSB office
General Aviation Accidents
Parties
FAA
FAA report
20160812014399A
Case key
93841

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 student pilot's improper pitch control during the landing flare, which resulted in a porpoise and substantial damage to the engine mount.

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.

Use of equip/info: aircraft controlPersonnel issues › Task performance · Student/instructed pilotCessna 152: 115 casesAll aircraft: 9,295 casesProbable cause
Performance/control parameters: pitch controlAircraft › Aircraft oper/perf/capability · Not attained/maintainedCessna 152: 14 casesAll aircraft: 526 casesProbable cause
Object/animal/substance: sign/markerEnvironmental issues › Physical environment · Contributed to outcomeCessna 152: 5 casesAll aircraft: 214 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 student pilot reported that during a short field landing, she flared a "little bit too high". She pushed the yoke forward, and the nose wheel impacted the ground first, subsequently the airplane porpoised and impacted a taxiway edge identifier light on the edge of the runway. The student pilot further reported that after she applied "heavy" brakes she taxied the airplane to the ramp area without further incident. The airplane sustained substantial damage to the engine mount. According to the student pilot there were no preimpact mechanical failures or malfunctions with the airframe or engine that would have precluded normal operation. The Federal Aviation Administration has published the Airplane Flying Handbook FAA-H-8083-3A (2004). This handbook discusses porpoising and states in part: In a bounced landing that is improperly recovered, the airplane comes in nose first setting off a series of motions that imitate the jumps and dives of a porpoise—hence the name. The problem is improper airplane attitude at touchdown, sometimes caused by inattention, not knowing where the ground is, mistrimming or forcing the airplane onto the runway. Ground effect decreases elevator control effectiveness and increases the effort required to raise the nose. Not enough elevator or stabilator trim can result in a nose low contact with the runway and a porpoise develops. Porpoising can also be caused by improper airspeed control. Usually, if an approach is too fast, the airplane floats and the pilot tries to force it on the runway when the airplane still wants to fly. A gust of wind, a bump in the runway, or even a slight tug on the control wheel will send the air plane aloft again. The corrective action for a porpoise is the same as for a bounce and similarly depends on its severity. When it is very slight and there is no extreme change in the airplane's pitch attitude, a follow-up landing may be executed by applying sufficient power to cushion the subsequent touchdown, and smoothly adjusting the pitch to the proper touchdown attitude.

Factual narrative

The student pilot reported that during a short field landing, she flared a "little bit too high". She pushed the yoke forward, and the nose wheel impacted the ground first, subsequently the airplane porpoised and impacted a taxiway edge identifier light on the edge of the runway. The student pilot further reported that after she applied "heavy" brakes she taxied the airplane to the ramp area without further incident. The airplane sustained substantial damage to the engine mount. According to the student pilot there were no preimpact mechanical failures or malfunctions with the airframe or engine that would have precluded normal operation. The Federal Aviation Administration has published the Airplane Flying Handbook FAA-H-8083-3A (2004). This handbook discusses porpoising and states in part: In a bounced landing that is improperly recovered, the airplane comes in nose first setting off a series of motions that imitate the jumps and dives of a porpoise—hence the name. The problem is improper airplane attitude at touchdown, sometimes caused by inattention, not knowing where the ground is, mistrimming or forcing the airplane onto the runway. Ground effect decreases elevator control effectiveness and increases the effort required to raise the nose. Not enough elevator or stabilator trim can result in a nose low contact with the runway and a porpoise develops. Porpoising can also be caused by improper airspeed control. Usually, if an approach is too fast, the airplane floats and the pilot tries to force it on the runway when the airplane still wants to fly. A gust of wind, a bump in the runway, or even a slight tug on the control wheel will send the air plane aloft again. The corrective action for a porpoise is the same as for a bounce and similarly depends on its severity. When it is very slight and there is no extreme change in the airplane's pitch attitude, a follow-up landing may be executed by applying sufficient power to cushion the subsequent touchdown, and smoothly adjusting the pitch to the proper touchdown attitude.

Aircraft

Registration
N48440
Reported as
Cessna 152
Category
Airplane
Serial number
15280910
Built
1977
Airframe hours
21,986.8
Engine
Lycoming O-235-L2C, 110 horsepower, reciprocating
Damage
Substantial damage
Flight
Instructional · Part 91
Operator
Hillsboro Aero Academy
Registered owner
Hillsboro Aero Academy
Airworthiness certificate
Standard, Normal; Standard, Utility
Last inspection
Annual · July 29, 2016
Departed
HIO · Hillsboro, OR
Destination
HIO · Hillsboro, OR
Flight plan
Company VFR
Airport
HIO · Portland-Hillsboro, runway 31L, 6,600 × 150 ft, asphalt
Equipment
Stall warning system, Satellite tracking 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
Student pilot
Age
19
Injuries
None
Certificate
Student
Medical
Class 3, With waivers/limitations
Seat
Left
Restraint
3-point
Flight hours
105.5 total · 105.5 in this make and model · 6 as pilot in command · 60 in the last 90 days · 21 in the last 30 days · 5 in the last 24 hours

Weather

Conditions
Visual (VMC) · Day
Wind
160° at 3 knots
Visibility
10 statute miles
Lowest ceiling
None
Temperature
93 °F, dew point 54 °F
Altimeter
29.97 inHg
Observed at
KHIO

Docket · 2

The files NTSB released with the investigation on October 27, 2016, on NTSB’s docket system: statements, records, photos and specialists’ reports. 2.3 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.