Jim Macklin wrote:
The parking brake on the BE 23/24 and 76 uses a lock that
stops the master cylinder from bleeding fluid back from the
brake assemblies. It is a simple device. The brakes are
not designed to be used for long term parking since they do
not compensate for temperature changes. If the hot brakes
are set and then cool the pressure and therefore the brake
releases. Even if the brakes are cool, over the night, the
air temperature will drop and the brakes release. Worse, if
you set the parking brake when it is cool or cold and then
the temperature goes up, the pressure increases locking the
brake solid and can damage the system. Often the only way
to get the parking brake to release is to open the brake
bleeder valve and that will require time and a mechanic to
re-bleed the brakes.

-snip

I think temperature extremes like you mentioned, complexity, and weight
considerations are all reasons why the russians dropped hydraulics in
favor of pneumatics on many of their aircraft. I have a russian Yak 52
and the starting, brake, and flap systems are all pneumatic. It's nice
not to have to worry about whether you battery will crank in the
morning.

FlynCatfish