NW Phantom Upgrade program worked like this:

Flight Eligibility: US to Europe, US to Asia, Asia to US, within Asia. The reason Europe to the US didn't work is because all of the European stations are managed by KL or third party staff (and I believe they ran on a completely different mainframe. I might be wrong about this fact).

Elite Eligibility: Platinum and Gold Elite only.

How it worked: based on seat availability up to five elites as defined above would be upgraded to the WBC cabin at the gate, usually 15 minutes before boarding. NW wasn't forthcoming with the exact criteria for selecting the five lucky flyers but it was generally believed to be Plat first, Gold second. Then within the elite ranks it was based on LTV (long term value) to NW as well as either YTD EQM or Lifetime EQM. It *appeared* that the value of the specific ticket you were flying on didn't play too big of a role.

This program was designed to specifically reward those travelers that have stuck with NW for the long haul if you will.

My experience: I only missed one international upgrade while this program was in effect (technically two but that's a different story). The upgrade I missed was MSP-AMS and there were five people upgraded so there were a lot more HVC's on that flight who outranked me. I don't have my records in front of me but I enjoyed the phantom upgrade on DTW-AMS (several times), MSP-AMS, SEA-NRT, ICN-NRT, NRT-SEA, etc.

Hope this helps.

PS - there were times I was upgraded after I had already boarded. NW was always VERY GOOD about coming on board to move someone up who had been upgraded, domestic or international.

-RM