Narrative:

Ord was on an east plan operation. [Crj-900] departed runway 10L; was a pmpkn northbound jet. Ord tower issued a 040 heading and switched. Then; they launched [a B747]; also a pmpkn northbound jet on a 040 heading off of 10L. There was the required 4 miles between B category aircraft. Once [the crj-900] was well into the departure airspace (outside of tower's airspace) I issued a 340 heading to begin to get them into my climb area. At this point; [the crj-900] was southeast of the ord arrival stream; and would never cross it; so this turn was necessary to initiate a climb. The turn; caused the separation with [the crj-900] and [the B747] to deteriorate; however not to decrease below 4 miles. Once [the B747] was 7-8 miles northeast of ord; I initiated a similar turn with them; and gave them a 320 heading to begin to build spacing required for the center between the two. Both aircraft were still unable to climb due to arrival traffic for ord; as well as a point out that was taken on [another] departure that was climbing south; and topping my departure traffic. Then; ord launched [another crj-900] off of runway 9R. [This aircraft] was a raynr northbound jet (which is east of the pmpkn). Initially they assigned; or at least planned a 360 heading; as indicated by the first departure strip scanned. They then changed that; and issued a 020 heading and shipped [the second crj-900]. This caused [the second crj-900] to pass behind [the B747] with less than adequate wake separation. In an effort to avoid it; I climbed [the B747] to 6000; but [the second crj-900] still passed through the wake of the heavy. In this instance; route relationship was never developed. The raynr jet should have been on the same heading initially as the pmpkn; or further east. Not west of them. This caused the problem. Also; these aircraft departed different runways; so I suspect there is some lack of coordination or procedure deficiency in the tower as well. Sadly; one potentially remedy to this solution will never be used; due to lack of funding. But familiarization trips between facilities could easily mitigate such issues.

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Original NASA ASRS Text

Title: C90 TRACON Controller reported he was unable to prevent a wake turbulence encounter between a CRJ-900 and a B747 because of procedure limitations.

Narrative: ORD was on an East Plan operation. [CRJ-900] departed Runway 10L; was a PMPKN northbound JET. ORD tower issued a 040 heading and switched. Then; they launched [a B747]; also a PMPKN northbound jet on a 040 heading off of 10L. There was the required 4 miles between B category aircraft. Once [the CRJ-900] was well into the departure airspace (Outside of Tower's airspace) I issued a 340 heading to begin to get them into my climb area. At this point; [the CRJ-900] was southeast of the ORD arrival stream; and would never cross it; so this turn was necessary to initiate a climb. The turn; caused the separation with [the CRJ-900] and [the B747] to deteriorate; however not to decrease below 4 miles. Once [the B747] was 7-8 miles Northeast of ORD; I initiated a similar turn with them; and gave them a 320 heading to begin to build spacing required for the center between the two. Both aircraft were still unable to climb due to arrival traffic for ORD; as well as a point out that was taken on [another] departure that was climbing south; and topping my departure traffic. Then; ORD launched [another CRJ-900] off of Runway 9R. [This aircraft] was a RAYNR northbound jet (which is east of the PMPKN). Initially they assigned; or at least planned a 360 heading; as indicated by the first departure strip scanned. They then changed that; and issued a 020 heading and shipped [the second CRJ-900]. This caused [the second CRJ-900] to pass behind [the B747] with less than adequate wake separation. In an effort to avoid it; I climbed [the B747] to 6000; but [the second CRJ-900] still passed through the wake of the heavy. In this instance; route relationship was never developed. The RAYNR jet should have been on the same heading initially as the PMPKN; or further east. Not west of them. This caused the problem. Also; these aircraft departed different runways; so I suspect there is some lack of coordination or procedure deficiency in the Tower as well. Sadly; one potentially remedy to this solution will never be used; due to lack of funding. But familiarization trips between facilities could easily mitigate such issues.

Data retrieved from NASA's ASRS site 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.