Yes I know the best answer is don't do it. And that's what I'm probably going to recommend. But do to continuously shifting plans my parents now have an itinerary that spans 3 tickets. Sweet.

It goes something like this.
Jfk-Tpe on BR in C
Tpe-bkk on TG in C
And BKK-LPQ on Bangkok airlines.

I feel that the flights on BR/TG shouldn't be a big problem given that they are both star alliance but the last leg is what I'm concerned about. I've built in enough time for them to exit and reclaim if necessary but just wanted to see what yall thought.

Bangkok airlines is listed as an interline partner for both Thai and EVa so theoretically it might work. Practically I feel like it's going to be up to to the whims of the check in agent at jfk. Anyone ever do anything crazy like this before?

Thanks

Fdw

It all depends on the layover times, which you have not stated. If the layovers are tight, prohibiting baggage reclaim / recheck action, they'll be in trouble. Then again if this is not one PNR and one of the legs operates late, causing them to miss a connection, they are also in trouble. You are no doubt aware of this.

I've connected from Thai to Bangkok before and it's pretty easy. (assuming everything is timely, etc.)

It's theoretically possible as long as their check in agent knows how to look up interline agreements for all involved carriers. I've attempted something very similar 2 weeks ago and they were going to do it (NH) but the agent was a domestic agent and didn't know how to look up interline agreements for CX (to SA). I couldn't push it because we had 10 minutes until they closed the boarding gate so just checked to the domestic transit point and rechecked all the way (CX to SA) there. With NH domestic agents (basically everyone at Haneda regardless of domestic or international flight) it takes a supervisor to do any interlining usually because the regular counter agents just aren't used to doing it, Japan domestic is almost exclusively point to point flying.

2.5 hours in TPE, 4.5 hrs in BKK....

It's a little tight and I'm definitely counting/hoping that at least the BR-TG interline will happen. The third one is what I'm most concerned about.

This trip kept evolving over the course of a year and that's what we ended up with.....

FDW

4.5 hours in BKK should be fine. You do not have to reclaim the bags. The two airlines are interline partners. http://www.thaiairways.com/en_TH/Terms_condition/interline_partner.page. People's experiences on other airline combos are irrelevant.

Interline is baggage through check on a single ticket. Airlines can be interline partners and yet refuse to through check bags on separate tickets.

2.5 hours in TPE is okay as long as everything is on time. It wouldn't take much delay to cause a problem though.

Just to close the loop, my parent's were able to interline their baggage across 3 separate tickets.
JFK-TPE on BR
TPE-BKK on TG
BKK-LPQ on PG.

FDW

^

My main concern would have been the agent's expertise and/or willingness to spend extra time getting it done at JFK.

I've interlined across two PNRs, one major alliance and one non-alliance interline partner. While I was successful and the agent was willing, she had to make a phone call to figure out *how* to do it. It took about 15 minutes to get it done and tagged correctly.

I can see 3 PNR's causing someone to not want to try and make up a rule about how it's not possible. Star-to-Star is a no brainer, but it wouldn't have surprised me if the JFK agent said "You'll need to get bags in BKK."

Glad it all worked out as desired.