Bill Z 0 Posted October 8, 2021 Share Posted October 8, 2021 Good afternoon - a couple of questions on hydraulics. 1. My understanding is that the CRJ700 does not drive hydraulic systems from the APU other than system 3 indirectly via the electric pump. If I start the APU (no engines yet) and switch 1 & 2 on the overhead to ON I see full 3000 PSI pressure on their systems - I expected to see nothing? 3A works as expected to pressurise to 3000 when switched on. 2. If I follow the tutorial I start engines and have 1, 2 and 3B set to AUTO and 3A set ON - all good. If I switch 3A to off then I lose IB spoilers which I don't understand because 3B is still AUTO so presumably would supply the system? If I start APU and set 1, 2 and 3B to ON then everything works with APU and after engine start... Confused Oh - should have mentioned that I love this plane - so much fun and work after so much time in the A320 - excellent value for money Aerosoft! Link to comment Share on other sites More sharing options...
KuntaKinte 210 Posted October 8, 2021 Share Posted October 8, 2021 4 hours ago, Bill Z said: My understanding is that the CRJ700 does not drive hydraulic systems from the APU other than system 3 indirectly via the electric pump. If I start the APU (no engines yet) and switch 1 & 2 on the overhead to ON I see full 3000 PSI pressure on their systems - I expected to see nothing? Pump 1A and 2A are engine driven pumps (EDP). All other pumps are electrically operated AC motor pumps (ACMP). Therefore, all 3 systems can provide hydraulic power even without running engines. The toggle switches on the overhead panel only control the ACMP. The switch of pump 3A only has an ON and OFF position, because under normal conditions it operates continously. 4 hours ago, Bill Z said: If I switch 3A to off then I lose IB spoilers which I don't understand because 3B is still AUTO so presumably would supply the system? The task of the AUTO position is to trigger the associated B-pump with a flapsetting > 0 (take-off, approach). The reason is an increased hydraulic demand => higher flight control deflection due to low airspeeds. In addition it maintains hydraulic pressure on system 1 and 2 in the event of an engine failure in these critical phases. Link to comment Share on other sites More sharing options...
Bill Z 0 Posted October 9, 2021 Author Share Posted October 9, 2021 Thank you Matthias! All much clearer now which means I can stop fretting Cheers Link to comment Share on other sites More sharing options...
Danny Vincken 21 Posted October 9, 2021 Share Posted October 9, 2021 Hydraulics are not fully modelled, and FOR ME that is a very big disappointment. Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.