Online check-in is your best bet. However, you must get Aloha's record locater number for this to work. United's PNR won't work to check in on Aloha's website. You'll need to call United and ask them for the Aloha Record Locater. If you get a clueless UA staffer, then call Aloha and tell them what flight you're on and your name and they can look it up for you.

IF when you try the online check in and it doesn't work, even with Aloha's Record Locater, then call Aloha back and ask them for their (not United's -- which they probably won't have) e-ticket number. (It's not -- like UA's -- 016xxxx but I forget what the opening designator is). Every once in awhile when on an AQ award using UA miles I couldn't do online check in, even with the AQ Record Locater. But the e-ticket number worked fine. (Or Aloha Pass FF #)

You don't have to exit security to go from UA to AQ in KOA. You should be able to get your boarding passes from the AQ gate agent.

But if you want a few extra minutes to not be standing in a line, do your Aloha boarding passes online.

One more hint: AQ's FF tracking system is so archaic that if you sign up for AQ frequent flyer program, and have them put your AlohaPass Miles # in the record when you call (which is also another way you can do online check-in) you'll probably get Aloha miles for the interisland award segments.

I have learned to do this every time I redeem a UA interisland ticket on AQ: I call Aloha and have them put our AlohaPass number(s) in our record (which, as I say, you can also use for online check in). I have gotten AlohaPass miles every time. They seem to take four months to show up, but they do show up.

Hope that helps.... Feel free to ask any follow-on questions