<prompt> Pedzisa mutsara unotevera: Muna 1970, boka revanokwira makomo pamwe chete naHeckel vakaronga kushanyira Alaska. Chinangwa chavo chakakanganiswa nehurumende yechiKomonisiti yeCzechoslovakia. Kutevera  <response>: kudzvinyirirwa kwePrague Spring muna 1968, zvakanga zvisingabviri kuenda kunyika dzokuMadokero. Boka racho rakachinja zvavakanga varonga ndokusarudza kukwira makomo ari muCordillera Blanca yokuPeru. Heckel nevamwe vake vakati wandei vakaronga kusiya rwendo rwacho uye kuisa pfungwa dzavo pakudzidza uye kunyoresa tsika dzevanhu vokuPeru. Zvisinei, pashure porufu rwomumwe wavatungamiriri veboka racho, mukwikwidzi Ivan Bortel, vakamanikidzwa kugara mumusasa navamwe vose veboka racho. Pana 1 June 1970, Heckel nevamwe vake vaida kuparadzana nevamwe vose vaiva muboka racho. Nenzira yakafanana, dutu rakakonzerwa nokudengenyeka kukuru kwePeru rakaviga musasa wavo pasi peHuascarán musi waMay 31, 1970, zuva risati raenda. Mitezo yose yechikwata chacho yakafa. 