V-Rally 4

This achievement can be obtained in Quick play from the Main menu. Select Extreme-Khana on the USA Airbase level and choose a relatively fast vehicle to maximise airtime. Now proceed around the track as normal and you will come to a section that you are required to accelerate up and over a plane. If you get a good enough run up here you can easily hit the 40 meters required for the achievement.

The easiest and quickest course I found to do this on, is the Canada Driving Test. After you go a little ways through the woods, you'll come to a big empty air field. There are a bunch of little ramps in a row (where you can achieve this at a high enough speed), but also a really tall ramp perpendicular to a long runway. It's easy to clear 2-3 times that distance with any vehicle.