This is a common bug in Yosemite. Please try the following on your MacBook Pro:
Open System Preferences (gear icon on the dock)
Open Network
Click on WiFi on the left to highlight it
Click Advanced at the lower right of the window
Click the TCP/IP tab
Make sure that the setting for Configure IPv6 is set to Link Local Only
Click OK
Click Apply in the next window that appears
Now click on Ethernet on the left panel to highlight it
Click Advanced
Ciick TCP/IP
Make sure that the setting for Configure IPv6 is set to Link Local Only
Click OK
Click Apply
Restart the Mac
Power off the AirPort router for a few seconds and then power it back up
Check to see if the AirPort will now appear in AirPort Utility