Just shy of 40 of the devices are in use so far, primarily near bars in Paris’ entertainment regions as well as 17 around major buildings.

The two-year trial isn’t meant to fine anyone. Rather, it’s meant to both test the viability of the technology and determine the noise levels that lead to penalties. However, people with souped-up rides might not want to get too comfortable. A draft law due for a vote this fall will let local officials experiment with noise radar fines, and Villeneuve-le-Roi intends to take advantage of it if and when the law takes effect. You might have one more incentive to drive a quiet EV — you’ll hardly make a sound even if you mash the throttle.

You wouldn’t have to wait long, either, as taxis could take off every six minutes.

There are already machinations underway. Aeroports de Paris has to pick a site for a flying taxi hub in Paris by the end of 2019, and it should be ready within 18 months. The team will test the link through an “existing helicopter corridor,” according to ADP’s Edward Arkwright.

There are many pieces that have to fall into place for this to work. The taxis themselves have to both be safe enough to fly and last long enough on battery. The partners also have to ensure that the taxis mesh well with existing infrastructure and regulations. If all goes smoothly, though, you may not have to hop into a ground-based vehicle until you’re already in the City of Lights. This could also serve as a test case for other cities that want to see how well flying taxis cope with major events.

The change has been years in the making, and on May 20th, three other units of measurement — the ampere, kelvin and mole — will also get new definitions. Those proved to be easier to update, as they weren’t based on a Victorian-era lump in France. The kilo will now correspond to the mass of an exact number of photons, or particles of light, of a particular wavelength. With this change, the kilo will be defined in terms of seconds and the meter, which are physical constants and therefore more reliable than a man-made object.

For most of us, the new definitions won’t change much, but for the scientific community it’s a historic moment. It will give researchers far more accurate tools with which to make measurements and that could help reexamine the laws of physics. As Terry Quinn, emeritus director of the International Bureau of Weights and Measures (BIPM), previously told Engadget, “This is the most important decision that the BIPM has made in maybe 100 years, which may be a slight exaggeration, but at least since 1960 when they adopted the International System of Units.”