Pilot reports of departure names and numbers that are too similar which causes confusion.

Attributes
ACN	1184244
Time
Date	201406
Local Time Of Day	1201-1800
Place
Locale Reference	DEN.Airport
State Reference	CO
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Make Model Name	B737-700
Operating Under FAR Part	Part 121
Flight Phase	Climb
Route In Use	Other EMMYS3 SID EEONS3
Flight Plan	IFR
Person 1
Function	Captain Pilot Not Flying
Experience	Flight Crew Last 90 Days 172
Person 2
Function	First Officer
Experience	Flight Crew Last 90 Days 247
Events
Anomaly	ATC Issue All Types Deviation - Procedural Published Material / Policy Deviation - Procedural Clearance Deviation - Track / Heading All Types

Narrative:

We did our clearance brief; flight brief; and departure brief. Pre departure clearance; route page 2; and legs pages were all viewed and briefed. All was confirmed on our ipads. On push back; we were asked which SID we were on and responded with the eeons 3 as per our route. We were cleared to taxi to [runway] 34R. Prior to takeoff; we were asked about our first fix. I was the pilot not flying and responded eeons 3 nuggs. We were then cleared for takeoff. On our climbout; we were queried as to our SID assignment. I responded the eeons 3. The controller indicated we were cleared via the emmys 3. After a bit of checking he informed us to fly the remainder of the EEONS3 and we switched frequencies. We went back to our pre departure clearance to confirm that we read it correctly. There was a change that was immediately above our route. Emmys 3 was directly over the eeons 3. We briefed the clearance off the pre departure clearance but the similarities were too subtle and the change was missed.

Original NASA ASRS Text

Title: Pilot reports of departure names and numbers that are too similar which causes confusion.

Narrative: We did our clearance brief; flight brief; and departure brief. PDC; Route page 2; and LEGS pages were all viewed and briefed. All was confirmed on our iPads. On push back; we were asked which SID we were on and responded with the EEONS 3 as per our route. We were cleared to taxi to [Runway] 34R. Prior to takeoff; we were asked about our first fix. I was the pilot not flying and responded EEONS 3 NUGGS. We were then cleared for takeoff. On our climbout; we were queried as to our SID assignment. I responded the EEONS 3. The Controller indicated we were cleared via the EMMYS 3. After a bit of checking he informed us to fly the remainder of the EEONS3 and we switched frequencies. We went back to our PDC to confirm that we read it correctly. There was a change that was immediately above our route. EMMYS 3 was directly over the EEONS 3. We briefed the clearance off the PDC but the similarities were too subtle and the change was missed.

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.