Frederick Valentich (June 9, 1958 – October 21, 1978)
I’d never heard about this young man’s disappearance until yesterday. Here’s Cash Peters’ take:
Even Wikipedia has an entry for Valentich‘s disappearance.

His birth time is unknown, so I rectified the chart to highlight this mysterious event (Neptune) @ age 20. There are three inconjuncts, two of which form a Yod (Finger of God) pointing at Mars.
Moon Inconjunct Uranus
With this aspect you must learn to control sudden outbursts of emotion that occur at difficult times when you least expect it. Also, your present home life may not be a stable situation in which you can grow up emotionally secure and confident. A particular incident when you were very young may have given you the feeling that you can’t count on anything or anyone for support. Later in life, you may try very hard to get away from anything that reminds you of your earliest childhood, even if your childhood has not been difficult. You just feel that you have to get away and go somewhere else.
Mars Inconjunct Neptune
With this aspect you must learn to stand up for yourself and demand your rights forthrightly and directly. Often you feel that you don’t have enough energy to assert yourself or that any such effort would be futile. Unfortunately, some people with this aspect learn to work behind the scenes or dishonestly. Others simply give up or take a defeatist attitude toward life.
Mars Inconjunct Pluto
This aspect sometimes means that you are the victim of aggressive energies in someone else, that you always seem to attract forceful persons who give you a hard time. Either they never let you have your own way, or they may be rather brutal, physically and psychologically. Learn to recognize such persons in advance and avoid them. Also think about why you are attracted to them, since in fact you may be quite fascinated by their forcefulness.
Does this young man qualify as someone born under a bad sign?
Last Contact with This World?
There is speculation that Frederick’s plane when down in Bass Strait (between mainland Australia and Tasmania). It is presumed he drowned. But his body has never been found, and therein lies the mystery.

As this moment is known to authorities, I am treating it as his moment of death. But what if, like Cash Peters suggests, Frederick’s soul was removed from this dimension and moved to another? And is he still stuck there? Hmm. I wonder.

His natal North Node conjunct the event’s Sun @ 28° Libra gives me pause: this may, in reality, be the whole point of his short life. He gave himself to the aliens for them to do as they wished with him. The proof? His natal Saturn is conjunct the event’s Part of Fortune @ 22° Sagittarius.