File:Vertical airspeeds of Boeing Max 737s in 2018-2019 crashes.jpg

Summary
This is a graph of publicly available flight data, for the two flights. The source data was provided by FlightRadar24 (https://twitter.com/flightradar24/status/1104676048317362177 and possibly other tweets/posts).
 * Other information:

It is believed to be public domain, but if not, it would be usable under free use doctrine, because 1/ the data cannot be provided from other sources than the few bodies that log aircraft satellite data, so fair use would reasonably apply to its reuse, and 2/ the production of a simple graph of an ordinary type, like this, from this type of public reusable data, is insufficiently creative to give further copyright to the grapher (for example, any regraphing of the same data would look substantively the same, expect for minor choices such as line colors and scale).

Graphs of this data have also been reused on several websites, in simplified and detailed form. The detailed form is more relevant to our article, because it is more exact (hence useful to a reader, especially one with experience in aircraft) and it specifically shows the 20-21 second fluctuations which third parties have noted as a key feature, which is probably of use to a reader.

Examples of other uses/portrayals:
 * https://indianexpress.com/article/world/why-investigators-fear-the-two-boeing-737s-crashed-for-similar-reasons-5625563 (same)
 * https://www.nytimes.com/2019/03/14/world/boeing-737-max-ethiopian-airlines.html (same)
 * http://newstier.com/trump-grounds-all-737-max-flights-after-ethiopian-airlines-disaster (rounded)
 * https://www.bbc.co.uk/news/world-africa-47605265 (somewhat rounded)

Licensing
See c:Template:PD-chart.