Commercial Fixed Wing
Flight Crew Instrument; Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 166; Flight Crew Total 8784; Flight Crew Type 8784
Confusion; Troubleshooting
Aircraft Equipment Problem Critical; Ground Event / Encounter Other / Unknown
Flight Crew Overcame Equipment Problem; General Flight Cancelled / Delayed
Aircraft; Company Policy
I am submitting this report because This is the second time I've experienced this situation. After sending an email to [the] Manager the first time and not getting a response; I am submitting this report. It has been a relatively new procedure to leave hydraulic switches off during preflight inspection. It used to be that hydraulics switches were always left on. Because the hydraulic pumps were off during our preflight inspection; we did not observe the hydraulic leak that was present. During the 'Pushback' checklist when the hydraulic switches were finally turned on; we received an 'RF' message on the EICAS within about 4-5 seconds. I then contacted Maintenance Control. Upon Maintenance Technician arriving; he advised we had a serious hydraulic leak spraying fluid all over the wheel well. Long story short; we ended up being almost 2 hours delayed getting the leak repaired. If we had NOT received the 'RF' message; we would've most likely had taken off with this leak and would've gotten a B hydraulic low quantity or even worse loss of hydraulic B pressure inflight!I've asked many people in several chief pilot offices; and sent emails to training and no one has offered a reason; other than standardize with other fleet type. I believe this is a safety issue. Leaving the hydraulic pumps off during preflight makes observing possible leaks impossible.
An Air Carrier pilot reported a change in flight deck configuration procedures could result in aircraft departing with undetected maintenance issues.