Cle controller described an airspace incursion when an aircraft initiated a descent issued to a same...

Narrative:

While working the inner low position (final controller) the outer controller (feeder position) handed off to me air carrier XXXX however air carrier XXXY took the frequency change. Air carrier XXXY checked in with me and I was expecting air carrier XXXX. On initial contact with me I over emphasized the [last digit] in the call sign after the pilot checked in calling himself air carrier XXXY. I issued air carrier XXXX a decent clearance over emphasizing the [last digit] in the call sign again. Air carrier XXXY read back the decent clearance and I restated air carrier XXXX. At that time the outer controller told me that air carrier XXXX was still on his frequency so looked at all of his traffic to see if any aircraft took an incorrect decent clearance and saw that he had a air carrier XXXY and in fact that aircraft was descending. There were no traffic conflictions and I pointed out the traffic to the cle departure position since the aircraft would be entering his airspace. The point out was approved and I kept air carrier XXXY on my frequency till he was switched to the tower on final. Continue to work with the airlines to remove similar sounding call signs. Also for me to not assume that over emphasis is enough to make sure the right aircraft received the correct clearance.

Original NASA ASRS Text

Title: CLE Controller described an airspace incursion when an aircraft initiated a descent issued to a same company aircraft with a similar sounding four digit flight number.

Narrative: While working the Inner Low position (Final Controller) the Outer Controller (Feeder position) handed off to me Air Carrier XXXX however Air Carrier XXXY took the frequency change. Air Carrier XXXY checked in with me and I was expecting Air Carrier XXXX. On initial contact with me I over emphasized the [last digit] in the call sign after the pilot checked in calling himself Air Carrier XXXY. I issued Air Carrier XXXX a decent clearance over emphasizing the [last digit] in the call sign again. Air Carrier XXXY read back the decent clearance and I restated Air Carrier XXXX. At that time the outer controller told me that Air Carrier XXXX was still on his frequency so looked at all of his traffic to see if any aircraft took an incorrect decent clearance and saw that he had a Air Carrier XXXY and in fact that aircraft was descending. There were no traffic conflictions and I pointed out the traffic to the CLE departure position since the aircraft would be entering his airspace. The point out was approved and I kept Air Carrier XXXY on my frequency till he was switched to the Tower on final. Continue to work with the airlines to remove similar sounding call signs. Also for me to not assume that over emphasis is enough to make sure the right aircraft received the correct clearance.

Data retrieved from NASA's ASRS site as of July 2013 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	1038507
Time
Date	201209
Local Time Of Day	1801-2400
Place
Locale Reference	CLE.Airport
State Reference	OH
Aircraft 1
Make Model Name	EMB ERJ 145 ER/LR
Operating Under FAR Part	Part 121
Flight Phase	Cruise
Flight Plan	IFR
Aircraft 2
Make Model Name	EMB ERJ 145 ER/LR
Operating Under FAR Part	Part 121
Flight Phase	Cruise
Flight Plan	IFR
Person 1
Function	Approach Departure
Qualification	Air Traffic Control Fully Certified
Events
Anomaly	ATC Issue All Types Deviation - Procedural Published Material / Policy

Cle controller described an airspace incursion when an aircraft initiated a descent issued to a same company aircraft with a similar sounding four digit flight number.