It is unfortunate that this is going to just result in a criminal filing against him.

While it was irresponsible, no one was hurt and reporting these vulnerabilities in the "appropriate" manner would likely result in the company trying to cover up the vulnerability citing some sort of DRM / trade secrets reasoning.

For this reason I am glad that he did this.

There are other sources of the same story - here are some.

This one has significant discussion: https://news.ycombinator.com/item?id=9558615

    Hacker told F.B.I. he made plane fly sideways
    (aptn.ca)

    Feds Say That Banned Researcher Commandeered a Plane
    (wired.com)

https://news.ycombinator.com/item?id=9556690

    Researcher may have adjusted airplane controls from in-flight entertainment-FBI
    (theverge.com)

    Security researcher claimed to hack, control plane in flight
    (engadget.com)

    Hacker 'made plane climb' after taking control through in-flight system
    (telegraph.co.uk)

    Security researcher hacks plane mid-flight
    (arstechnica.com)

    FBI: researcher hacked plane in-flight, causing it to "climb"
    (securityaffairs.co)

    Hacker told FBI he made plane fly sideways after cracking entertainment system
    (aptn.ca)

    Researcher hacks flight system of plane, making it climb
    (dailymail.co.uk)