Korean Air flies from Terminal 4 at Heathrow, not Terminal 3 (that's Asiana's terminal).
You can pay to use various Heathrow lounges but there is no such facility available to you in Terminal 4.
Korean uses the Skyteam lounge in Terminal 4, which is accessible by anyone holding Skyteam Elite Plus status [and their guest(s)] departing Terminal 4 on a Skyteam flight, and by passengers in First and Business class departing Terminal 4 on a Skyteam flight.
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I would say not as its not 1 airlines lounge its a group's so unless korean has a deal with a certain credit card to issue you with an invitation then very unlikely.
You could always ask the staff (At the check-in) if their is any elite plus members checking in that day and wait and see if they could invite you with their spare place.
This is the only way i can see you getting in. And of course you would be taking the risk that they already have some one to invite. But if an elite plus does check-in and he/she is traveling alone,
I don't see why they wouldn't allow your to be their guest.. But its still their decision.
All us flyers went through the stage of not getting lounge access until we attained status its not really nice but that's just how things work. But the rewards are worth it when it does come.
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Originally Posted by kushty
Ok, thanks. I won't wait to ask someone to let me in, I just can't do that.
That's right. You should not approach strangers to beg them to bring you into a lounge as their guest.
You can look for a restaurant or bar near the gate where you could purchase food or a drink as a way to have a nice place to relax and wait for your flight. Some people enjoy walking around the airport, people watching, looking in airport stores, etc. when they have extra time.
Though you may not want to approach someone directly at the airport, I certainly wouldn't be shy about using the meet-up threads in the various forums here for an invite. Check out all of the Skyteam carriers at T4 on here and see what you can drum up.