The last of the three aircraft is a modern biplane. This incorporates a number of rare orange elements including right and left 8 x 3 wedge plates which make up the wings and have only previously appeared in three sets, a 3 x 4 wedge brick only previously found in two sets, and a 3 x 6 round half plate with a 1 x 2 cutout which has only previous appeared in a single set in this colour and which forms the tailplanes. Similar to the two jets the tail fin is stickered rather than printed, as are the pair of 1 x 4 x 1 panels making up the sides of the cockpit. Unlike the jets, however, the instrument panel is stickered, which seems odd as there are existing printed 1 x 2 light bluish grey tiles which could have done an acceptable job. There are also a pair of stickers which represent the engine exhausts and which are applied to a couple of modified 2 x 4 x 1 1/3 bricks with curved top which sit just behind the propeller; applying these neatly to the curved surface takes a steady hand, and that’s also the case for the pair of checkerboard stickers which are stuck onto the propeller cowl. As if stickered exhausts weren’t enough, there are also a couple of light bluish grey exhaust pipes with Technic pin which emerge from the propeller cowl and run along either side of the fuselage. They’re entirely superfluous given the presence of the stickered exhausts but they still look cool regardless!
@josekalel: I think the size of the terminal is kept in check for price reasons more than anything. This is a $100 set, and while bigger and pricier City sets exist, they tend to be few in number. What's more, the disadvantage to having a plane wide enough to seat two rows of passengers is that it inevitably takes up a big portion of the budget even for a larger set like this one. If the set were just the airport with no plane, then the terminal could probably be around twice this size at the very least… but then the set would not offer such a complete play experience.
The programmable Lego brick which is at the heart of these robotics sets has undergone several updates and redesigns, with the latest being called the 'EV3' brick, being sold under the name of Lego Mindstorms EV3. The set includes sensors that detect touch, light, sound and ultrasonic waves, with several others being sold separately, including an RFID reader.[52]

Bag 4 finishes the fuselage and all that is left are the engines and tail section.  You'll notice that this aircraft has a bathroom on board as well as some storage for a non-existent flight attendant.  I think this is the first time that LEGO has put some additional details into aircraft besides just seats.  Also there is only one pilot for a 2 seat cockpit in the set.  
Colour-wise, it is mainly yellow, with only a dash of green and red, and a little more white, there to break it up. The worker has space to stand and drive the vehicle, and has a walkie talkie attached on the side of the car. Around the other side is a coiled-up, what I assume is a, fuel pump. It looks pretty good when coiled up on the side of the car. Stickers come into use again here, this time for the number plates.