Besiege

VERY EASY - just download my very simple anti-air vehicle from the workshop. Search for "Duke's Freighters" (Full name is "Duke's Freighters Achievement")

3 shots, 3 kills. (I pumped the cannons up to 1.5x because the cannon balls kept bouncing off the ships!)

First kill - turn to your right, fire. That's it!
The second kill - move towards the next closest airship, get just about close enough for the bomb sheep to come after you, around there should be okay, fire!
The third kill - you have a couple of options but I found it easier to drive around the edges, avoid the bomb sheeps, park RIGHT under the 3rd ship. Aim the cannons straight up. Move your camera so you are looking up. FIRE!

Done.

First off - the xbox guide won't help you here, as the level in the windows version has four ships rather than three.

For this I used the ANTI AIRCRAFT machine by Michel P Soares.

Clear these out in order:
Bomb yaks - clear them with the crossbow, C key.
First two ships closest to the ground - fireball, raise with H key.
Highest ship on the distant right - fireworks with the T key.
Ship on the distant left - cannons with the Q+E keys. This will break the machine, so save this for last.

When using the fireball, approach the low ship with cannons from the back, as the cannons will fire and destroy your machine from the sides.
When using the fireworks and the cannons, look straight up from under your machine to make sure you get a hit.
Get out of the way of the ships as they fall.

On the Isle of Tolbrynd (second world) is a level called "The Dukes Dear Freighters" (Level 20). You have to destroy 3 of the freighters that are in the air by any mean, but to get this achievement you cant use any of the flying blocks

What i did was make a basic car in the shop of an capital i, a wheel in each corner and a steering hinge to turn it left and right, make 3 pillars pointing upwards in the middle of the top and bottom and in the middle of the i itself, place one canon on each of these pillars pointing upwards and modify them by hovering over one, push the button, go down to the power tab and increase it to about 1.50x, now do the same for the other 2 canons but make sure to change the button you use to shoot it with, i had one canon using the standard , the next using and the last using

When you have sorted the canons, place 2 (or more) crossbows on the front to be able to kill any cows carrying bombs (make sure you dont have the shoot button on any of the ones you already assigned for the canons!)

When you have built the car and everything is good to go (i recommend testing your canons) drive to the right and kill the cow carrying a bomb on its back, then drive under the freighter and shoot one of your canons, THIS MAY OR MAY NOT BLOW THE CANON AND PILLAR APART! SO BE CAREFUL! ALSO BE CAREFUL OF ANY FALLING DEBRIS FROM THE FREIGHTER AS IT CAN STILL DAMAGE YOU, ESPECIALLY THE SPINNING BLADES!

Now drive to the left and be sure to take out any cows with bombs before they get too close to you, and take out the second freighter

The last freighter is towards the back and is quite high up, but your canons should be able to hit it no problem, if your having trouble aiming, aim your camera down as far as it can go and drive underneath the freighter until you cant see your build, make sure your build is parallel as it will make it easy to hit

This is how i done it, other people will have other ways (and probably a lot better designs!) but it worked

Anti-Aircraft Guide

Basically all I made was a 4 wheeled vehicle that had 2 crossbows on the front for killing the bomb yachts and built a tall structure on my vehicle and attached 6 crossbows with all of them pointing up at the ships. Parked under each ships and hit the propellers. Hitting them anywhere else don't seem to do much damage.

Hope this works like it did for me. Sometimes the propellers are stubborn. Adding more crossbows pointing up is always a plus.

On the 20th level, in the 2nd campaign area, you will find this mission. You have to destroy 3 flying machines without using flying parts, simple enough. Let's build us some AAA.

Use logs to make a cross or plus sign, then use supports to connect them for stability. Next, place steering blocks and use to edit them to turn off Auto Return. Next, place steering hinges on each one and edit them to turn off auto return as well, and change their controls to something like so they don't use the same controls as the blocks. Lastly, place cannons on each hinge, facing the same direction as the hinges, and edit them to have 200% power and change the controls to so its easy to remember which gun is which.

Now, just start up the level, take aim and fire. No risk from the bomb sheep, and with that much power you are definitely going to hit whatever you aim at. You even have one extra shot in case you miss!