Hydraulics B757
Hi Hawk21M
Thank you.We re kind of building an Hydraulic Mater here.
-1,2,3,7,8,9,12,13:understood.Thanks.
-4 So the reason is because only one PCU unnit is operating?So it has to do with Spoilers Control Modules?assymetric spoilers deployment?that makes sense for a Max crosswind limitation.But still one piece missing to me:there are 6 SCM s,and just one SCM failure will cause assymetrical spoiler deployment.And spoilers are driven by the 3 Hyd Systems.So why there is no crosswind limitation with one Hyd system failure and there is with 2 Hyd failure?Plus I m looking at the diagram, and all the spoilers are symetrically Hydraulically driven:L HYD drives 3,5,8,10,R Hyd 1,12 and C hyd 4,9.So lets say you loose C and R Hyds,with the remaining L Hyd you should have spoilers 3 and 5 on L side and 8 and 10 on R side.may be I m mixing things.The question is why no crosswind limitation with ! system INOP
-11-Ok,then when Normal and Alt brakes fail and we push RSVR BRK,we get the reserve brakes,the C2 is isolated for the brakes and full brake authority is available.But then what is the accumulator?I though it was the level below the stack pipe,but that s the liquid used for reserve brakes right?I mean,when do you loose Reserve brakes to have only available the accumulator Pressure"aand pneumatically pressurized?you mean that when you get the RSV light,other than a low qty,that could indicate low Hyd Fluid pressurization Pressure,that can tell you that if you loose Normal,Alt and reserve,you could have problems with your accumulator Pressure for your 2-3 applications?
Thank you like always