Narrative:

We were cruising at FL310, the captain tuned radio #2 to get arriving ATIS for dfw. I was handling communication #1 as per company policy. ATC started to give me holding clearance and descent altitude. It caught me off guard and I read back the holding clearance which was 'air carrier X, descend and maintain FL240 and hold northeast at the birle intersection as published, efc will be XA25.' I read back the clearance and questioned the descent altitude. ATC confirmed to descend and maintain FL240. At that point I dialed in the altitude given and started the descent to FL240. The autoplt was engaged during this entire time. Moments later the captain finished copying arriving ATIS and I filled him in on ATC instruction including the descent to FL240. The captain plugged in the published hold at birle and said 'do you like that?' I quickly looked at my pfd and my arrival chart and said, 'yes, execute.' on our way from FL260 we received a TCASII traffic alert. The captain pointed to this aircraft at about 10-11 O'clock position. I continued to monitor my descent and began a speed reduction for the hold. Just at that moment, we received an RA TCASII alert 'traffic, traffic' with a climb or descend (cannot remember at this time). I took the autoplt off and said 'autoplt disengaged.' I complied with the RA and adjusted power as needed. The captain was calling out TCASII profiles. ATC then came back with 'air carrier X, climb to FL250 or FL260, turn right to heading of XXX, what altitude were you assigned?' the captain replied 'air carrier X, FL240, we were responding to a TCASII RA.' the controller came back and said we were assigned FL270. This was the first time I had heard FL270. We were given additional instruction to fly and returned to our original flight plan. We continued the flight with no further incident.

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Original NASA ASRS Text

Title: FLT CREW OF CL65 EXPERIENCE TCASII RA WHEN THEY WERE EITHER GIVEN OR MISHEARD A CLRNC TO DSND.

Narrative: WE WERE CRUISING AT FL310, THE CAPT TUNED RADIO #2 TO GET ARRIVING ATIS FOR DFW. I WAS HANDLING COM #1 AS PER COMPANY POLICY. ATC STARTED TO GIVE ME HOLDING CLRNC AND DSCNT ALT. IT CAUGHT ME OFF GUARD AND I READ BACK THE HOLDING CLRNC WHICH WAS 'ACR X, DSND AND MAINTAIN FL240 AND HOLD NE AT THE BIRLE INTXN AS PUBLISHED, EFC WILL BE XA25.' I READ BACK THE CLRNC AND QUESTIONED THE DSCNT ALT. ATC CONFIRMED TO DSND AND MAINTAIN FL240. AT THAT POINT I DIALED IN THE ALT GIVEN AND STARTED THE DSCNT TO FL240. THE AUTOPLT WAS ENGAGED DURING THIS ENTIRE TIME. MOMENTS LATER THE CAPT FINISHED COPYING ARRIVING ATIS AND I FILLED HIM IN ON ATC INSTRUCTION INCLUDING THE DSCNT TO FL240. THE CAPT PLUGGED IN THE PUBLISHED HOLD AT BIRLE AND SAID 'DO YOU LIKE THAT?' I QUICKLY LOOKED AT MY PFD AND MY ARR CHART AND SAID, 'YES, EXECUTE.' ON OUR WAY FROM FL260 WE RECEIVED A TCASII TFC ALERT. THE CAPT POINTED TO THIS ACFT AT ABOUT 10-11 O'CLOCK POS. I CONTINUED TO MONITOR MY DSCNT AND BEGAN A SPD REDUCTION FOR THE HOLD. JUST AT THAT MOMENT, WE RECEIVED AN RA TCASII ALERT 'TFC, TFC' WITH A CLB OR DSND (CANNOT REMEMBER AT THIS TIME). I TOOK THE AUTOPLT OFF AND SAID 'AUTOPLT DISENGAGED.' I COMPLIED WITH THE RA AND ADJUSTED PWR AS NEEDED. THE CAPT WAS CALLING OUT TCASII PROFILES. ATC THEN CAME BACK WITH 'ACR X, CLB TO FL250 OR FL260, TURN R TO HDG OF XXX, WHAT ALT WERE YOU ASSIGNED?' THE CAPT REPLIED 'ACR X, FL240, WE WERE RESPONDING TO A TCASII RA.' THE CTLR CAME BACK AND SAID WE WERE ASSIGNED FL270. THIS WAS THE FIRST TIME I HAD HEARD FL270. WE WERE GIVEN ADDITIONAL INSTRUCTION TO FLY AND RETURNED TO OUR ORIGINAL FLT PLAN. WE CONTINUED THE FLT WITH NO FURTHER INCIDENT.

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.