CEN17LA340

NTSB accident investigation · Cessna 310G · Broomfield, CO · September 1, 2017

Accident · No injuriesLimited investigationFinal report
Date
September 1, 2017, 15:15 local (21:15 UTC)
Place
Broomfield, CO
Injuries
2 uninjured
Damage
Substantial damage
Phase of flight
Landing
Aircraft
N8957ZCessna 310G
Defining event
Landing-flare/touchdown: Landing gear collapse
Weather
Visual (VMC) · Day
Status
Completed · report March 18, 2019
Report
Approved by Office Director
NTSB office
Central Region
Parties
FAA - Denver FSDO
FAA report
20170901011169A
Case key
95959

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

A collapse of the right main landing gear due to a bent pushrod, which precluded the gear from fully extending. The reason for the bent pushrod could not be determined based on the available information.

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.

Landing gear system: landing gear actuatorAircraft › Aircraft systems · Damaged/degradedCessna 310G: 1 caseAll aircraft: 54 casesProbable cause
Not determinedNot determined › Not determined · Unknown/Not determinedCessna 310G: 1 caseAll aircraft: 2,247 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

The private pilot reported that, upon touchdown in the retractable gear, multi-engine airplane, he experienced a "mushy feeling" and aborted the landing even though the gear down indicator light was illuminated. He made another landing attempt with the same results, but after the second attempt, he noted that neither the red gear-up light nor the green gear-down light were illuminated. Ultimately, the pilot diverted to a nearby tower-controlled airport. The tower personnel confirmed that the right main landing gear was not fully extended. Attempts to lower the landing gear using emergency procedures were unsuccessful, and the pilot landed the airplane, during which the right landing gear collapsed. Subsequent examination revealed that a pushrod from the gear motor was bent, which likely resulted in the inability of the right landing gear to fully extend. The reason for the bent pushrod could not be determined.

Factual narrative

On September 1, 2017, about 1515 mountain daylight time, a Cessna 310G airplane, N8957Z, sustained substantial fuselage damage during a landing gear collapse while landing on runway 30R at the Rocky Mountain Metropolitan Airport (BJC), near Broomfield, Colorado. The pilot and passenger were not injured. The airplane was registered to and operated by Zero Energy Aviation, LLC under the provisions of Title 14 Code of Federal Regulations Part 91 as a training flight. Visual meteorological conditions prevailed for the flight, which operated on a visual flight rules flight plan. The flight originated from the Boulder Municipal Airport (BDU), Boulder, Colorado, about 1315 and the intended destination was the Greeley-Weld County Airport (GXY), Greeley, Colorado. The pilot reported that during approach to GXY, he lowered the landing gear and noted a that the green gear-down indicator illuminated. Upon touchdown, he felt a "mushy feeling" and aborted the landing, leaving the landing gear in the down position. He noted that the gear-down indicator was still illuminated. He attempted another landing with the same result and initiated another aborted landing, again leaving the landing gear in the down position. At this time neither the red gear-up light nor the green gear-down light were illuminated. The pilot left the landing gear in the down position and proceeded toward BDU, which was the airplane's home base. He attempted to contact ground personnel at BDU to assist in verifying the landing gear position. There was no response on the common traffic advisory frequency (CTAF), and he elected to contact the air traffic control tower (ATCT) at BJC. After establishing communication with BJC ATCT, he performed several fly bys of the tower and tower personnel confirmed that the right main landing gear was not fully extended. After making another attempt to lower the landing gear using the emergency checklist, the pilot landed on runway 30R. During the touchdown, the landing gear collapsed. According to the pilot, maintenance personnel found that the pushrod extending from the gear motor to the right main landing gear was found bent. The reason for the bent pushrod was not determined. Federal Aviation Administration records indicated that the pilot held a private pilot certificate with an airplane single engine land rating. He did not hold a multiengine rating. The airplane was a twin-engine retractable-gear airplane.

Aircraft

Registration
N8957Z
Reported as
Cessna 310G (G)
Category
Airplane
Serial number
310G0057
Built
1962
Airframe hours
4,035
Engines
Cont Motor IO-470 -D, 260 horsepower, reciprocatingCont Motor IO-470-D, 260 horsepower, reciprocating
Damage
Substantial damage
Flight
Instructional · Part 91
Operator
Zero Energy Aviation LLC
Registered owner
Zero Energy Aviation LLC
Airworthiness certificate
Standard, Normal
Last inspection
Annual · April 30, 2017 · 80 hours before
Departed
BDU · Boulder, CO
Destination
GXY · Greeley, CO
Flight plan
VFR
Airport
BJC · Rocky Mountain Metropolitan, runway 30R, 9,000 × 100 ft, asphalt
Equipment
Stall warning system

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
63
Injuries
None
Certificate
Private
Airplane ratings
Single-engine land
Medical
Class 3, With waivers/limitations
Seat
Left
Restraint
3-point
Flight hours
13,842 total · 7,259 in this make and model

Weather

Conditions
Visual (VMC) · Day
Wind
30° at 6 knots
Visibility
20 statute miles
Lowest ceiling
None
Temperature
86 °F, dew point 37 °F
Altimeter
30.20 inHg
Observed at
BJC

Docket · 2

The files NTSB released with the investigation on July 5, 2018, on NTSB’s docket system: statements, records, photos and specialists’ reports. 609 KB 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 N8957Z · 1

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