Narrative:

Flight ord-mem. Normal departure under VMC conditions. Takeoff was from runway 22L. We were instructed to turn to a southerly heading after takeoff and to climb and maintain 5000'. Upon reaching cleanup altitude, engine thrust was reduced to maintain 'quite EPR' profile as per our standard operating procedures. At the ord 8 DME arc, and passing 3400' MSL, ord departure asked us what our altitude was. When we told the controller, he informed us that we were supposed to be at 4000' MSL by the 8 DME arc. He then gave us a new heading and a frequency change. Based on the following data, this particular situation was almost a 'gotcha' from the start. A) the restriction is printed in very fine print in the text of the ord 8 SID. Many other sids/stars throughout the country that have hard altitudes and distances have the arcs and altitude/DME restrictions depicted on them to facilitate the crews on their departures/arrs. I have now drawn it on there myself. In a high density control zone such as ord, the depiction should be mandatory. There is plenty of room to print this on the SID. B) older model large transport's (those with smaller engines) will always be marginal with regard to compliance with that particular restriction. Especially given the fact by the time the aircraft is on the climb out from 22L, it is already 'well south' of the ord VOR. This makes it even more difficult to comply with if the 'quiet EPR' climb profile noise abatement procedures are followed. On a hot day at maximum gross takeoff weight unquestionably an older large transport could not make this restriction. As indicated in the text, the crew should notify tower/departure as soon as possible that this is the case. However, 90 percent of the time I feel that this is a 'maybe' situation. On a normal day, at normal takeoff weight, it will be close. That is the danger in this particular SID. Very few crews will probably say anything because they think that the restriction can be met. C) this is usually a climbing turnout which of course further diminishes aircraft performance. As per airline procedures, we do not increase to 'normal' climb thrust until 3000' AGL or in this case approximately 3700' MSL. In summation, I feel that given the pilot workload in a high volume traffic area such as chicago, with normal cleanup procedures, noise abatement profiles, ATC turns and staying heads up for traffic outside the cockpit, this 4000' restriction is a trap. Perhaps not in a newer aircraft, but in an older large transport it is. The elimination of 'quiet EPR' and especially depicting this arc with its restrictions (and the northern arc as well) could perhaps alleviate such complications in the future.

Related reports:

Google
 

Original NASA ASRS Text

Title: FLT CREW OF LGT DEPARTING 22L AT ORD UNABLE TO MAKE 8 MILE ARC 4000 MSL RESTRICTION.

Narrative: FLT ORD-MEM. NORMAL DEP UNDER VMC CONDITIONS. TKOF WAS FROM RWY 22L. WE WERE INSTRUCTED TO TURN TO A SOUTHERLY HDG AFTER TKOF AND TO CLIMB AND MAINTAIN 5000'. UPON REACHING CLEANUP ALT, ENGINE THRUST WAS REDUCED TO MAINTAIN 'QUITE EPR' PROFILE AS PER OUR STANDARD OPERATING PROCS. AT THE ORD 8 DME ARC, AND PASSING 3400' MSL, ORD DEP ASKED US WHAT OUR ALT WAS. WHEN WE TOLD THE CTLR, HE INFORMED US THAT WE WERE SUPPOSED TO BE AT 4000' MSL BY THE 8 DME ARC. HE THEN GAVE US A NEW HDG AND A FREQ CHANGE. BASED ON THE FOLLOWING DATA, THIS PARTICULAR SITUATION WAS ALMOST A 'GOTCHA' FROM THE START. A) THE RESTRICTION IS PRINTED IN VERY FINE PRINT IN THE TEXT OF THE ORD 8 SID. MANY OTHER SIDS/STARS THROUGHOUT THE COUNTRY THAT HAVE HARD ALTS AND DISTANCES HAVE THE ARCS AND ALT/DME RESTRICTIONS DEPICTED ON THEM TO FACILITATE THE CREWS ON THEIR DEPS/ARRS. I HAVE NOW DRAWN IT ON THERE MYSELF. IN A HIGH DENSITY CTL ZONE SUCH AS ORD, THE DEPICTION SHOULD BE MANDATORY. THERE IS PLENTY OF ROOM TO PRINT THIS ON THE SID. B) OLDER MODEL LGT'S (THOSE WITH SMALLER ENGINES) WILL ALWAYS BE MARGINAL WITH REGARD TO COMPLIANCE WITH THAT PARTICULAR RESTRICTION. ESPECIALLY GIVEN THE FACT BY THE TIME THE ACFT IS ON THE CLIMB OUT FROM 22L, IT IS ALREADY 'WELL SOUTH' OF THE ORD VOR. THIS MAKES IT EVEN MORE DIFFICULT TO COMPLY WITH IF THE 'QUIET EPR' CLIMB PROFILE NOISE ABATEMENT PROCS ARE FOLLOWED. ON A HOT DAY AT MAX GROSS TKOF WEIGHT UNQUESTIONABLY AN OLDER LGT COULD NOT MAKE THIS RESTRICTION. AS INDICATED IN THE TEXT, THE CREW SHOULD NOTIFY TWR/DEP AS SOON AS POSSIBLE THAT THIS IS THE CASE. HOWEVER, 90 PERCENT OF THE TIME I FEEL THAT THIS IS A 'MAYBE' SITUATION. ON A NORMAL DAY, AT NORMAL TKOF WEIGHT, IT WILL BE CLOSE. THAT IS THE DANGER IN THIS PARTICULAR SID. VERY FEW CREWS WILL PROBABLY SAY ANYTHING BECAUSE THEY THINK THAT THE RESTRICTION CAN BE MET. C) THIS IS USUALLY A CLIMBING TURNOUT WHICH OF COURSE FURTHER DIMINISHES ACFT PERFORMANCE. AS PER AIRLINE PROCS, WE DO NOT INCREASE TO 'NORMAL' CLIMB THRUST UNTIL 3000' AGL OR IN THIS CASE APPROX 3700' MSL. IN SUMMATION, I FEEL THAT GIVEN THE PLT WORKLOAD IN A HIGH VOLUME TFC AREA SUCH AS CHICAGO, WITH NORMAL CLEANUP PROCS, NOISE ABATEMENT PROFILES, ATC TURNS AND STAYING HEADS UP FOR TFC OUTSIDE THE COCKPIT, THIS 4000' RESTRICTION IS A TRAP. PERHAPS NOT IN A NEWER ACFT, BUT IN AN OLDER LGT IT IS. THE ELIMINATION OF 'QUIET EPR' AND ESPECIALLY DEPICTING THIS ARC WITH ITS RESTRICTIONS (AND THE NORTHERN ARC AS WELL) COULD PERHAPS ALLEVIATE SUCH COMPLICATIONS IN THE FUTURE.

Data retrieved from NASA's ASRS site as of August 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.