Basically, the only thing that the two sets have in common is that they both have planes. However there is quite a bit of difference on the inside of the planes. There are a lot more details in the Friends plane. In addition to the seats, there is a rolling service cart complete with refreshments, emergency lighting as well as a larger galley and lav in the back of the plane.
While I like their characters, I really don’t like LEGO recycling their characters. I can make an exception for Bucky, who until this year has only been made available as a pretty exclusive (and pricey) polybag but having this exact same Captain America show up in so many sets is pretty damn lazy. If a super hero minifig has been used a year ago, it really isn’t too much to ask for LEGO to update it slightly.
Bag 6 starts the airport terminal.  Like most CITY builds, they are meant for play so it's really only half a building.  It includes one minifigure and the revolving door entrance.  While the entrance is cool looking, it's about twice the height of a minifigure and there isn't enough physical space for one actually to fit through the door.  I'm not a fan of the design.

Anyway, I think this may be my favorite LEGO City air terminal yet! It may not be as big as some previous ones, but it feels really coherent. The plane is nice as well with its white, orange, and blue stripes. I agree that Heartlake City Airport's plane has a cozier and more detailed interior, though. It does really highlight some of the differences between Friends and City, with City opting for capacity over comfort and function over flair.
The rest of the model is pretty standard for a Marvel release. Most of the larger sets revolve around a vehicle and/or small structure. This one doesn’t disappoint in that respect. First up, you get the airport control tower. It’s fairly uninteresting, although they have added an exploding wall-play feature which kinda makes up for it. Otherwise, though, it’s simply a tower. In addition to that you get a small baggage car, which is pretty neat. In fairness, as cute as it is, it feels like an attempt to bump up the number of pieces. Lastly, the set comes with a Quinjet. This particular vehicle is considerably smaller than the previous two minifigure-scale Quinjets that Lego gave us last year and in 2012. That said, it’s a great model with some great features.
Honestly I have asked many of my friends and only a number even know about LEGO’s removal tool piece, and this is already an updated one from their previous grey piece. Friends, family, strangers – this is a lifesaver. It wouldn’t save you from stepping on a LEGO piece but it helps a tonne in getting pieces off of each other without damaging your nails. Or teeth. Don’t ask.
The rest of the model is pretty standard for a Marvel release. Most of the larger sets revolve around a vehicle and/or small structure. This one doesn’t disappoint in that respect. First up, you get the airport control tower. It’s fairly uninteresting, although they have added an exploding wall-play feature which kinda makes up for it. Otherwise, though, it’s simply a tower. In addition to that you get a small baggage car, which is pretty neat. In fairness, as cute as it is, it feels like an attempt to bump up the number of pieces. Lastly, the set comes with a Quinjet. This particular vehicle is considerably smaller than the previous two minifigure-scale Quinjets that Lego gave us last year and in 2012. That said, it’s a great model with some great features.

The final two minifigures are the Biplane Pilot and the intrepid Wing Walker. Both of these minifigures share the same white torso which is printed with a flight suit design overlaid with dark red and bright light orange flames plus a logo over the left breast. The torso design is superb and it can at present only be found in this set. Both minifigures are provided with a reddish brown aviator cap and dark bluish grey goggles, and the pilot (below left) also gets an alternative to this headgear in the form of medium dark flesh mid-length hair which has only ever appeared in five sets in this colour.
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