What is the minimum oil temperature for T-6 engine start?

The minimum oil temperature for a T-6 engine start is critical for ensuring that the oil is adequately warmed to provide proper lubrication for the engine components. An oil temperature that is too low can lead to increased viscosity, which results in insufficient lubrication and can potentially cause engine damage during start-up.

For the T-6, the specified minimum oil temperature for engine start is -40°C. This temperature ensures that the oil can flow adequately and create a proper lubricating film over the engine's moving parts, thus preventing metal-to-metal contact. Starting the engine with oil temperatures below this limit can compromise the engine's reliability and performance.

Other oil temperature options are either too low, which would be detrimental to engine health, or more appropriate for operational conditions after proper warming during flight operations, rather than at the engine start phase.