Oliver Tree, the California-born singer-songwriter and rapper known for tracks like "Life Goes On," "When I'm Down" and "Miss You," died in a helicopter crash in Rio de Janeiro, according to CNN Brazil.

Oliver Tree's mother is speaking out about her son's tragic death.

A list of just some of the lives lost in such accidents includes: Patsy Cline — Piper PA-24 Comanche small airplane crashed in bad weather on March 5, 1963, killing Cline, 30, and fellow country artis...