SAO PAULO—Marília Mendonça, one of Brazil’s most popular singers and a Latin Grammy winner, died Friday in an airplane crash on her way to a concert. She was 26. Mendonça’s press office confirmed her death in a statement, and said four other passengers on the flight also perished. Their plane crashed between Mendonça’s hometown Goiania and Caratinga, a small city in Minas Gerais state located north of Rio de Janeiro. Minas Gerais state’s civil police also confirmed Mendonça’s death, without providing details about the cause of the accident, which occurred shortly before arrival. Photographs and videos show the plane laying just beneath a waterfall; Mendonça had posted a video this afternoon showing her walking toward the plane, guitar case in hand. On Friday evening, the news triggered an outpouring of sadness on social media from all corners of Brazil, including fans, politicians, musicians, and soccer players. Her Instagram account has …