Date: 201205
Local time of day: 1201-1800
Location: ROA.Airport, VA
Flight conditions: VMC
Light: Daylight
Aircraft: EMB ERJ 145 ER/LR
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Climb
Airspace: Class C ROA
ATC / advisory: TRACON ROA
Aircraft component: ILS/VOR
Component problem: Improperly Operated
Reporter organization: Air Carrier
Reporter function: Captain; Pilot Flying
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Human factors: Human-Machine Interface
Second reporter function: First Officer; Pilot Not Flying
Anomaly: Aircraft Equipment Problem Less Severe; Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Person Air Traffic Control
When detected: In-flight
Result: Air Traffic Control Issued Advisory / Alert; Air Traffic Control Issued New Clearance; Flight Crew Became Reoriented; Flight Crew Returned To Clearance
Contributing factors: Aircraft; Chart Or Publication; Human Factors; Procedure
Primary problem: Human Factors

Narrative: We got assigned the DIXXY SIX departure and then I proceeded to brief as it was my leg. I briefed the taxi; departure; special procedure and also; threats like the terrain in the area. I also set the TERR mode on my MFD for reference on the departure. I also told the First Officer to identify the LOC frequency as it was a pilot NAV departure. On the taxi; we noticed a momentary flag on the EHSI; it was a second; and then the flag went out of view. We both noticed it and briefed accordingly as it was VFR. As we took off and tried to track the 252 out of the LOC as per the departure First Officer armed the NAV at 400 FT and then it showed capture on the FMA. The FD was showing a shallow bank towards the left and I was correcting to center the LOC; which it was not. When passing 4;000 FT and climbing to 5;000; ATC said to us that we were 5 miles left of course. Then; ATC gave us a right turn direct to DILNNThe threat was that the DIXXY SIX departure uses the LOC from Runway 6. There was no notation on the departure about any reverse sensing effect and that's why we set the course to 252 as per the DIXXY SIX departure. It happens that we tracked the front course and we think we had reverse sensing on the EHSI. Obviously we caught it after ATC gave us the vector to DILNN. I hope that the company and the FAA can put this important notation on the departure for our crews to reference it. This is the only explanation I have on this event.


Second narrative: We briefed all threats for the departure including terrain. Since the departure is a pilot NAV departure; the Captain requested that I identify the LOC. As we taxied out to Runway 24; we noticed that there was a NAV flag; which went away before departure. As we took off at 400 FT; the Captain requested that NAV mode be armed; to track the 252 out of the Local frequency 111.1. The FMA showed captured; as we intercepted the LOC. The Captain followed the flight director and around 4;000 FT ATC told us that we were about 5 miles left of course and gave us a right turn direct DILNN.


Synopsis: EMB145 flight crew reports getting well off track flying the DIXXY 6 departure from ROA.  The crew set the depicted course of 252 degrees to fly the back course LOC departure.