Narrative:

We were cleared for takeoff out of ontario, ca, behind another aircraft, which I believe was a twin engine cessna. At 5850 ft we received a TCASII warning and RA. The traffic was at 6000 ft, about 3 mi ahead and climbing. We received an oral warning, traffic traffic descend descend, as well as a pitch guidance presentation to descend. I followed the pitch guidance presentation and descended to 5700 ft. The captain was watching traffic off the right, or south of us, but that was not the problem. He wanted me to keep the aircraft climbing, but I followed the advisory against his wishes. As I leveled off at 5700 ft, the traffic on the scope was now at 6100 ft. The captain took over control of the aircraft and begin climbing never seeing the traffic ahead, only reacting to the traffic off to the right, which was not the immediate problem. By the time the captain pulled the aircraft up, we were clearing the traffic ahead. I feel part of the problem was the horizontal situation indicator on the captain's side was not set on a close range, making it impossible to tell which aircraft was the threat. I did have my side set on the 10 mi range, making the traffic easy to pick out. I think it would be advisable to set it on a 10, or 20 mi range until you are out of the lower altitudes.

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Original NASA ASRS Text

Title: MLG FLC DISAGREES OVER RESPONSE TO TCASII RA.

Narrative: WE WERE CLRED FOR TKOF OUT OF ONTARIO, CA, BEHIND ANOTHER ACFT, WHICH I BELIEVE WAS A TWIN ENG CESSNA. AT 5850 FT WE RECEIVED A TCASII WARNING AND RA. THE TFC WAS AT 6000 FT, ABOUT 3 MI AHEAD AND CLBING. WE RECEIVED AN ORAL WARNING, TFC TFC DSND DSND, AS WELL AS A PITCH GUIDANCE PRESENTATION TO DSND. I FOLLOWED THE PITCH GUIDANCE PRESENTATION AND DSNDED TO 5700 FT. THE CAPT WAS WATCHING TFC OFF THE R, OR S OF US, BUT THAT WAS NOT THE PROB. HE WANTED ME TO KEEP THE ACFT CLBING, BUT I FOLLOWED THE ADVISORY AGAINST HIS WISHES. AS I LEVELED OFF AT 5700 FT, THE TFC ON THE SCOPE WAS NOW AT 6100 FT. THE CAPT TOOK OVER CTL OF THE ACFT AND BEGIN CLBING NEVER SEEING THE TFC AHEAD, ONLY REACTING TO THE TFC OFF TO THE R, WHICH WAS NOT THE IMMEDIATE PROB. BY THE TIME THE CAPT PULLED THE ACFT UP, WE WERE CLRING THE TFC AHEAD. I FEEL PART OF THE PROB WAS THE HORIZ SIT INDICATOR ON THE CAPT'S SIDE WAS NOT SET ON A CLOSE RANGE, MAKING IT IMPOSSIBLE TO TELL WHICH ACFT WAS THE THREAT. I DID HAVE MY SIDE SET ON THE 10 MI RANGE, MAKING THE TFC EASY TO PICK OUT. I THINK IT WOULD BE ADVISABLE TO SET IT ON A 10, OR 20 MI RANGE UNTIL YOU ARE OUT OF THE LOWER ALTS.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.