ZOB controller reported an aircraft was handed off to the wrong sector resulting in a near loss of s...

Narrative:

Aircraft X was southeast bound issued FL330 which is the top altitude of the next sector (sector 27) which I was planning on handing off to. I thought I directed the hand off to sector 27 but instead; by mistake; the hand off was directed to sector 26 which is the sector directly above sector 27. By the time my scan came back to aircraft X; the data block now displayed a t-altitude [temporary-altitude] of FL350 and sector 26 had the handoff.since I thought I flashed the handoff to sector 27; I assumed the sector 27 had flashed the aircraft through to sector 26 and they had entered the t-altitude. I then climbed aircraft X to FL350. Because I provide spacing for the ord line on the wynde arrival; I had brought up a data block on an ord arrival (aircraft Y at FL320) that was coming my way. At this point; aircraft X vs. Aircraft Y didn't look so good so I told aircraft X to expedite climb through FL330. Since I was operating under the assumption that sector 27 was okay with the situation I switched aircraft X to sector 26. Shortly after; I noticed that aircraft X was stopped at FL310.well; there are pros and cons to the flash through procedure; but in this situation; if there was no flash through procedure; I would've noticed that the wrong sector had the handoff and would've made coordination to rectify the situation.

Original NASA ASRS Text

Title: ZOB Controller reported an aircraft was handed off to the wrong sector resulting in a near loss of separation. Reporter mistakenly assumed the receiving Sector flashed through the aircraft to the next in line sector.

Narrative: Aircraft X was southeast bound issued FL330 which is the top altitude of the next sector (Sector 27) which I was planning on handing off to. I thought I directed the hand off to Sector 27 but instead; by mistake; the hand off was directed to Sector 26 which is the sector directly above Sector 27. By the time my scan came back to Aircraft X; the data block now displayed a T-altitude [temporary-altitude] of FL350 and Sector 26 had the handoff.Since I thought I flashed the handoff to Sector 27; I assumed the Sector 27 had flashed the aircraft through to Sector 26 and they had entered the T-altitude. I then climbed Aircraft X to FL350. Because I provide spacing for the ORD line on the WYNDE arrival; I had brought up a data block on an ORD arrival (Aircraft Y at FL320) that was coming my way. At this point; Aircraft X vs. Aircraft Y didn't look so good so I told Aircraft X to expedite climb through FL330. Since I was operating under the assumption that sector 27 was okay with the situation I switched Aircraft X to sector 26. Shortly after; I noticed that Aircraft X was stopped at FL310.Well; there are pros and cons to the flash through procedure; but in this situation; if there was no flash through procedure; I would've noticed that the wrong sector had the handoff and would've made coordination to rectify the situation.

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.

Attributes
ACN	1385456
Time
Date	201609
Local Time Of Day	1201-1800
Place
Locale Reference	ZOB.ARTCC
State Reference	OH
Environment
Light	Daylight
Aircraft 1
Make Model Name	Medium Large Transport Low Wing 2 Turbojet Eng
Operating Under FAR Part	Part 121
Flight Phase	Climb
Flight Plan	IFR
Aircraft 2
Make Model Name	Large Transport
Operating Under FAR Part	Part 121
Flight Phase	Cruise
Flight Plan	IFR
Person 1
Function	Enroute
Qualification	Air Traffic Control Fully Certified
Experience	Air Traffic Control Time Certified In Pos 1 (yrs) 16
Events
Anomaly	ATC Issue All Types Airspace Violation All Types Conflict Airborne Conflict Deviation - Procedural Published Material / Policy

ZOB controller reported an aircraft was handed off to the wrong sector resulting in a near loss of separation. Reporter mistakenly assumed the receiving sector flashed through the aircraft to the next in line sector.