ERA11LA221

NTSB accident investigation · Cessna 310F · Sanford, FL · April 1, 2011

Accident · No injuriesLimited investigationFinal report
Date
April 1, 2011, 15:45 local (19:45 UTC)
Place
Sanford, FL
Injuries
2 uninjured
Damage
Substantial damage
Phase of flight
Landing
Aircraft
N6781XCessna 310F
Defining event
Landing-landing roll: Landing gear collapse
Weather
Visual (VMC) · Day
Status
Completed · report August 15, 2012
Report
Approved by Office Director
NTSB office
Eastern Region Aviation
Parties
FAA/FSDO
FAA report
20110401005319A
Case key
78739

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 failure of the nose landing gear due to inadequate servicing of the nose gear strut reservoir.

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.

Landing gear system: nose/tail gear strut/axleAircraft › Aircraft systems · Incorrect service/maintenanceCessna 310F: 1 caseAll aircraft: 36 casesProbable cause
Maintenance: scheduled/routine maintenancePersonnel issues › Task performance · OtherCessna 310F: 1 caseAll aircraft: 320 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 flight instructor and private pilot were performing touch-and-go landings. While retracting the landing gear, they heard a loud bang. The gear-up light illuminated, indicating that all three landing gears were retracted and the doors were closed. The instructor concluded that the noise came from the landing gear doors closing into each other. The flight continued, and two more landings were planned: one touch-and-go and one full stop. The landing gear appeared to operate normally during the touch-and-go. Upon extending the gear for the full stop landing, the gear-down light failed to illuminate. After checking the gear down indicating system, a visual check with the tower controllers confirmed that all three landing gears were in the down position. During touchdown, the nose gear collapsed. A postaccident examination of the nose gear assembly revealed that the nose landing gear strut reservoir lacked air pressure and the fluid level was very low. This underserviced condition caused binding in the nose gear fork assembly and failure of a nose gear push rod, which prevented the nose gear from extending to the full down and locked position.

Factual narrative

On April 1, 2011, at 1545 eastern daylight time, a Cessna 310F, N6781X, registered to a private individual, incurred substantial damage to the fuselage after the nose gear collapsed during landing rollout at Sanford Orlando International Airport (SFB), Sanford, Florida. The certified flight instructor (CFI) and his private pilot-rated dual student were not injured. The instructional flight was conducted under the provisions of 14 Code of Federal Regulations Part 91. Visual meteorological conditions prevailed and no flight plan was filed. The flight originated from SFB at 1500. The CFI reported that after takeoff, while retracting the landing gear, a loud “bang” was heard. It was assumed by the CFI that the noise came from the landing gear doors closing into each other. The gear-up light illuminated indicating that the landing gear were retracted and the doors were closed. The flight returned to SFB for two planned landings; first a touch-and-go and then a full stop. On the first landing; the gear were extended and a gear-down light illuminated. A touch-and-go was conducted without incident. Upon extending the gear for the second landing, the gear-down light failed to illuminate. The landing gear were recycled, and the gear light gave a gear-up indication. Another gear extension was attempted, and a gear-down indication was not received. The CFI contacted the SFB tower to request a low fly-by for a visual inspection of the gear position. The tower controller reported all three gear were down and the airplane was cleared to land. The touchdown on the main gear was normal; but as weight was applied to the nose wheel, the nose gear collapsed. The airplane was examined by a Federal Aviation Administration (FAA) inspector under the direction of a NTSB investigator. The airplane was raised using aircraft jacks to take the weight off of the wheels. The nose gear shock strut trunnion assembly remained in the compressed position. Approximately one inch of the strut trunnion surface was visible. An attempt to retract the nose landing gear was unsuccessful, due to the strut fork assembly coming into contact with the nose landing gear door attachment brackets. The nose strut trunnion was manually extended out of the cylinder until approximately three inches of the piston surface was visible. The nose landing gear assembly was then manually raised up into the wheel well area and fully retracted. The nose landing gear strut trunnion reservoir was checked for air pressure and was totally empty of air. The strut trunnion reservoir was checked for fluid which was found to be very low. There were no signs of fluid leakage around the nose landing gear strut trunnion. A review of the maintenance logbooks did not reveal any prior discrepancies with the nose landing gear assembly.

Aircraft

Registration
N6781X
Reported as
Cessna 310F
Category
Airplane
Serial number
310-0081
Airframe hours
3,245
Engines
Cont Motor I0-470 SERIES, 260 horsepower, reciprocatingCont Motor I0-470 SERIES, 260 horsepower, reciprocating
Damage
Substantial damage
Flight
Instructional · Part 91
Operator
Edward Moon
Registered owner
Edward Moon
Airworthiness certificate
Standard, Normal
Last inspection
Annual · February 11, 2011 · 23 hours before
Departed
SFB · Sanford, FL
Destination
SFB · Sanford, FL
Airport
SFB · Orlando Sanford International, runway 27, 9,601 × 150 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
Flight instructor
Age
43
Injuries
None
Certificates
Flight instructor, Airline transport, Commercial
Airplane ratings
Multi-engine land, Single-engine sea, Single-engine land
Instrument ratings
Airplane
Medical
Class 2, With waivers/limitations
Last flight review
October 19, 2010
Seat
Right
Flight hours
2,400 total · 300 in this make and model · 1,965 as pilot in command · 40 in the last 90 days · 20 in the last 30 days · 1 in the last 24 hours

Weather

Conditions
Visual (VMC) · Day
Wind
290° at 11 knots, gusting 19
Visibility
10 statute miles
Lowest ceiling
None
Temperature
79 °F, dew point 46 °F
Altimeter
29.84 inHg
Observed at
SFB

Docket · 6

The files NTSB released with the investigation on June 26, 2012, on NTSB’s docket system: statements, records, photos and specialists’ reports. 3.2 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.