Narrative:

First officer was flying and we had a straight out departure from ord to the south with a slight tailwind. We needed to make 4000' by 8 DME for the ord 9 SID. I had misread the SID. On climb out, ATC appeared to give us a heading to go behind another aircraft, which was at 3000'. If we had made the SID restriction, there would not have been a problem, I don't think. We were between 3700 and 4000' at 8 DME (we were at 3000' at 6 DME, climbing about 1000 FPM at 160 KTS). A always monitor the SID until 4000', then do climb checks. But this time for some reason I did climb checks as soon as I had time. I think I let my guard down, probably because I was very tired. I have no problem with the way the trip was scheduled (early morning departure). I just was not used to that early hour. 1 thing I know now is that taking off on runway 22L, we were already 2.0 DME from VOR at rotation. I will take that into account in the future. Supplemental information from acn 176967: captain and I noticed we were at 3000' and 6 DME. That would leave 2 mi to climb 1000'. That wouldn't normally be a problem, but the tailwind made it close. When we were almost at 4000', departure control turned us to 15 degree heading for traffic, either departing or going into mdw. Later when the captain and I had thought about it, we wondered if controller had to turn us because we had not been at 4000' by 8 DME. Captain hadn't flown in 6 weeks and I'd flown 6 out of last 7 days, both which could have been factors. Also being a little complacent might have contributed, since we fly in/out of ord every day and always comply with the ord 9 departure.

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Original NASA ASRS Text

Title: ACR FLT CREW FAILS TO MAKE ALT RESTRICTION ON SID FROM ORD.

Narrative: F/O WAS FLYING AND WE HAD A STRAIGHT OUT DEP FROM ORD TO THE S WITH A SLIGHT TAILWIND. WE NEEDED TO MAKE 4000' BY 8 DME FOR THE ORD 9 SID. I HAD MISREAD THE SID. ON CLBOUT, ATC APPEARED TO GIVE US A HDG TO GO BEHIND ANOTHER ACFT, WHICH WAS AT 3000'. IF WE HAD MADE THE SID RESTRICTION, THERE WOULD NOT HAVE BEEN A PROB, I DON'T THINK. WE WERE BTWN 3700 AND 4000' AT 8 DME (WE WERE AT 3000' AT 6 DME, CLBING ABOUT 1000 FPM AT 160 KTS). A ALWAYS MONITOR THE SID UNTIL 4000', THEN DO CLB CHKS. BUT THIS TIME FOR SOME REASON I DID CLB CHKS AS SOON AS I HAD TIME. I THINK I LET MY GUARD DOWN, PROBABLY BECAUSE I WAS VERY TIRED. I HAVE NO PROB WITH THE WAY THE TRIP WAS SCHEDULED (EARLY MORNING DEP). I JUST WAS NOT USED TO THAT EARLY HR. 1 THING I KNOW NOW IS THAT TAKING OFF ON RWY 22L, WE WERE ALREADY 2.0 DME FROM VOR AT ROTATION. I WILL TAKE THAT INTO ACCOUNT IN THE FUTURE. SUPPLEMENTAL INFO FROM ACN 176967: CAPT AND I NOTICED WE WERE AT 3000' AND 6 DME. THAT WOULD LEAVE 2 MI TO CLB 1000'. THAT WOULDN'T NORMALLY BE A PROB, BUT THE TAILWIND MADE IT CLOSE. WHEN WE WERE ALMOST AT 4000', DEP CTL TURNED US TO 15 DEG HDG FOR TFC, EITHER DEPARTING OR GOING INTO MDW. LATER WHEN THE CAPT AND I HAD THOUGHT ABOUT IT, WE WONDERED IF CTLR HAD TO TURN US BECAUSE WE HAD NOT BEEN AT 4000' BY 8 DME. CAPT HADN'T FLOWN IN 6 WKS AND I'D FLOWN 6 OUT OF LAST 7 DAYS, BOTH WHICH COULD HAVE BEEN FACTORS. ALSO BEING A LITTLE COMPLACENT MIGHT HAVE CONTRIBUTED, SINCE WE FLY IN/OUT OF ORD EVERY DAY AND ALWAYS COMPLY WITH THE ORD 9 DEP.

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.