G-IV STARTING ENGINEs 

How to Start Engines on the Gulfstream IVSP. I will take you though an abbreviated flow then follow that up with another engine start using the G-IV Checklist. Refer to Gulfstream QRH Page NC-6 for Starting Engines. We start the Right Engine first for a few reasons. First, we want to check that the Utility Pump is working. With the Right Engine running, the Flight hydraulics will be operating. However, since the pressure is less than 800 PSI in the Combined hydraulic system (actually zero since the Left engine isn't running at this point)m, the Utility Pump (which is just a back up pump for the Combined hydraulic system) will turn ON (if armed). We also look for SINGLE RUDDER LIMIT message. The rudder gets hydraulics from both Combined and Flight System. As the right engine starts, hydraulic pressure will flow to the rudder, but since the left engine is not running, there will be NO Combined pressure, hence a SINGLE rudder limit message showing that only ONE hydraulic source is providing pressure to the rudder. Lastly, the Flight Data Recorder will begin operating when the Right Engine starts and the FLIGHT REC FAIL CAS message should be OUT. Want to thank Jay for recording this video.