LAX98LA065

NTSB accident investigation · Cessna 172RG · Van Nuys, CA · December 30, 1997

Accident · No injuriesLimited investigationFinal report
Date
December 30, 1997, 14:00 local (22:00 UTC)
Place
Van Nuys, CA
Injuries
2 uninjured
Damage
Substantial damage
Phase of flight
Landing
Aircraft
N5404VCessna 172RG
Weather
Visual (VMC) · Day
Status
Completed · report May 4, 1998
Report
Approved by Office Director
FAA report
19971230041269A
Case key
30016

From the NTSB’s public API. By law, NTSB reports can’t be used as evidence in lawsuits over the accident.

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Probable cause

The student and flight instructor's failure to verify that the landing gear was in the down position, and the design of the electrical system in which a single-point aircraft system malfunction (one open circuit breaker) disabled both the landing gear warning system and the main gear downlock switches.

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.

Wheels up landingLanding - flare/touchdown
Electrical system,circuit breaker - popped/trippedCause
Acft/equip,inadequate designManufacturerCause
Landing gear,gear locking mechanism - disabledFactor
Landing gear,gear warning system - disabledFactor
Gear extension - not verifiedFlightcrewCause

Analysis

The flight instructor stated that the student pilot had extended the landing gear on the downwind leg of the traffic pattern, but then retracted it after being told to go around by the control tower. On the second downwind leg, the student again placed the gear switch in the down position; however, neither the student nor the instructor visually verified that the gear was down and locked. During the final flare for landing, the instructor noted that the gear was not down and that the 5 amp gear warning circuit breaker had opened. He then closed the circuit breaker and noted the gear starting to extend, but it had achieved only an intermediate position at the time of touchdown. The airplane subsequently settled on to the runway and incurred damage to the underside, the right wing, and the right horizontal stabilizer. A review of the Cessna 172RG Service Manual, Drawing No. 2471000, 'Wiring Diagram-Landing Gear System' indicated that subject circuit breaker, in addition to providing power to the gear indicator lights and warning horn, also powers the main gear downlock switches and the stall warning horn.

Factual narrative

On December 30, 1997, at 1400 hours Pacific standard time, a Cessna 172RG, N5404V, was substantially damaged during landing with the gear partially extended at the Van Nuys, California, airport. There were no injuries to the flight instructor or student pilot. The flight departed Van Nuys on a local instructional flight and no flight plan was filed. Visual meteorological conditions prevailed for the personal flight.

The flight instructor stated in his report of accident that the student pilot had extended the landing gear on the downwind leg of the traffic pattern, but then retracted it after being told to go around by the control tower. On the second downwind leg, the student again placed the gear switch in the down position; however, neither the student pilot nor the instructor visually verified that the gear was down and locked. During the final flare for landing, the instructor noted that the gear was not down and that the 5 amp gear warning circuit breaker had opened. He then closed the circuit breaker and noted the gear starting to extend but it had achieved only an intermediate position at the time of touchdown. The airplane subsequently settled on to the runway and incurred damage to the underside, the right wing, and the right horizontal stabilizer.

A review of the Cessna 172RG Service Manual, Drawing No. 2471000, "Wiring Diagram-Landing Gear System" indicated that subject circuit breaker, in addition to providing power to the gear indicator lights and warning horn, also powers the main gear downlock switches and the stall warning horn. This was verified by a telephone conversation with the Cessna Aircraft Engineering Department.

Aircraft

Registration
N5404V
Reported as
Cessna 172RG
Category
Airplane
Serial number
172RG0522
Airframe hours
4,619
Engine
Lycoming O-360-F1A6, 180 horsepower, reciprocating
Damage
Substantial damage
Flight
Instructional · Part 91
Registered owner
Back Bay Construction, Inc.
Airworthiness certificate
Standard, Normal
Last inspection
Annual · December 11, 1997 · 4 hours before
Departed
VNY
Airport
VNY · Van Nuys, runway 34, 8,000 × 150 ft, asphalt

Flight crew

As NTSB recorded them. NTSB leaves out names.

Role
Pilot
Age
36
Certificates
Flight instructor, Airline transport
Airplane ratings
Single-engine land, Multi-engine land, Single-engine sea
Instrument ratings
Airplane
Medical
Class 1, Valid Medical--no waivers/lim.
Seat
Right
Flight hours
2,800 total · 75 in this make and model · 2,400 as pilot in command · 90 in the last 90 days · 30 in the last 30 days · 6 in the last 24 hours

Weather

Conditions
Visual (VMC) · Day
Wind
350° at 5 knots
Visibility
25 statute miles
Lowest ceiling
None
Temperature
82 °F, dew point 37 °F
Altimeter
29.00 inHg
Observed at
VNY, 1 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.