helicopter single hydraullic actuator capability

[tejas_kass]

For example in typical helicopter Nz-V envelop for 3T weightclass if dual hydraulic system is designed for 2.5g aerodynamic loads at 240kmph, what could be the single actuator capability (is it 50% or 75% of dualactuator capability) at design stage. The design for aerodynamic loads shouldbe upto 2.5g for dual system what should be the ‘g’ level aerodynamic loads for a single system.



Is there any references / literature available that helps toknow “in a dual hydraulic system, if one hydraulic system fails what should bethe ‘g’ which could sustain and safely land of a helicopter”.

awaiting answers please

regards
TEJAS

[Gomer Pylot]

Typically, only one hydraulic system is in operation at any one time. The second system is just a backup. Either system must be capable of handling the entire load.

[Akitomo]

A "DUAL" feature is redundancy as Gomer Pylot said.

In case of Bell 412, main (CYC & CLTV) actuators have two pistons which are fed 1000psi. Each piston has an effective piston area of 0.75sq inch. So, one (#1 or #2) actuator has a capabilty of 750lbs, which is to be 1500lbs in dual operation. We won't notice any difference between a single and a dual operation while operating flight controls.