No fatalities

20 Mar 2008: Cessna 210N — Cincinnati, OH

Cincinnati, OH, United States

On 20 Mar 2008, a Cessna 210N was involved in an aviation accident near Cincinnati, OH. No fatalities were reported. Investigators recorded the probable cause as: The pilot's decision to operate the airplane with a "dead" battery contrary to guidance provided by the Pilot's Operating Handbook. An additional cause was the pilot's failure to verify that the landing gear was fully down and locked prior to landing. This summary draws on records from NTSB; 12 related events involving the same aircraft type or operator are linked below.

SourcesNTSBPrimary reportUpdated 1778583330Data APIEditorial standards

A pilot experienced total electrical power loss after liftoff, returned for an immediate landing, but the main landing gear collapsed upon touchdown. Post-accident inspection found a discharged battery with low electrolyte.

Background

The pilot planned a local flight to evaluate recent maintenance and charge the aircraft's battery, which had lost its charge over the winter. The engine was started using ground power. After startup, both alternator out lights extinguished, indicating the alternators were online. The aircraft was equipped with a 28-volt dual alternator electrical system, showing 29 volts output, zero battery voltage, and a charging ammeter.

Flight

During the pre-takeoff run-up, all systems, including radios and GPS, were functioning normally. At liftoff, the pilot raised the landing gear handle, retracted the flaps, and reduced power to climb. Immediately, all electrical power was lost. The pilot chose to remain in the traffic pattern and land. He lowered the landing gear handle but did not perform the emergency gear extension procedure due to the urgency and attention required by other traffic.

Accident

Upon landing on runway 24 (3,499 feet by 75 feet, asphalt), the main landing gear collapsed, and the airplane departed the left side of the runway before stopping. The left horizontal stabilizer sustained skin and substructure damage.

Post-Accident Findings

A post-accident inspection revealed the battery had little or no electrolyte, with output measured at 8.3 volts and no current indication. Alternators and voltage regulators were tested under FAA supervision with no anomalies found. The Pilot's Operating Handbook (POH) stated that using the ground service plug receptacle to start an airplane with a dead battery or charge a dead battery in the airplane was not recommended, warning that failure to observe this could result in loss of electrical power during flight. The landing gear extension and retraction system uses an electric motor to provide hydraulic pressure; loss of electrical power prevented motor operation, requiring manual gear extension. The pilot commented that inspecting the battery fluid level before the flight might have prevented the accident.

Contributing factors

Causes

Pilot

Other contributing factors

Electrical power system — FailureIncorrect service/maintenanceInoperative