The correct procedure to align the IRSs in the RJ Professional is to set both IRS switches to ALN, input the aircraft’s position on the FMS POS INIT page, and then move the IRS switches to NAV. That will ensure that the IRSs will align in the fastest possible time.

However, it is worth considering that we have simulated the IRS Time To Nav (TTN) functionality of the real aircraft. This functionality means that the time it takes for the IRSs to align varies based on the aircraft’s present latitude. At latitudes close to the equator IRS alignment can be as quick as 2.5 minutes, but at latitudes of 70 degrees North/South, it can take as long as 15 minutes.

As a quality-of-life addition in the RJ Professional, it is possible to ‘fast align’ the IRS by quickly moving the IRS switch from OFF > ALN > NAV > ALN. The alignment will then be completed within 30 seconds of a position being entered into the FMS and will be indicated by the NAV OFF annunciators above the IRS switches flashing. At this point, the IRS switches can then be moved to NAV, and the EFIS displays will be ready for flight. 

The IRS will be automatically aligned when loading the aircraft on the runway, or when selecting the ‘Turnaround’ or ‘Ready For Takeoff’ states on the EFB.

Note: As a protection against accidental selection of the IRS switches from NAV > ALN, the IRS switches must be moved over a baulk between these two positions. This is replicated in this simulation of the RJ, and therefore, you must click the centre of the IRS switches to 'pull' the switch out over the baulk before moving them from NAV > ALN.