Rubuta ci gaba don wannan sakin layi - A cikin 1970, ƙungiyar masu hawa dutse tare da Heckel sun shirya ziyartar Alaska. Tsarin mulkin kwaminisanci na Czechoslovak ya hana niyyarsu. Bayan shafewa
na Prague Spring a shekarar 1968, kusan ba zai yiwu a yi tafiya zuwa kasashen yamma ba. Rukunin sun canza shirin su kuma sun yanke shawarar hawa tsaunuka a Cordillera Blanca na Peru. Heckel da abokan aikinsa da yawa sun shirya barin tafiyar kuma sun mai da hankali kan nazarin da kuma rubuta al'adun Peruvian. Duk da haka, bayan mutuwar daya daga cikin shugabannin tafiyar, mai hawa dutse Ivan Bortel, an tilasta su su zauna a sansanin tare da sauran masu binciken. A ranar 1 ga Yuni, 1970, Heckel da abokan aikinsa sun yi niyyar rabuwa da sauran kungiyar. Ba zato ba tsammani, ambaliyar da Babban Girgizar Kasa ta Peru ta haifar ta binne sansanin su a ƙarƙashin Huascarán a ranar 31 ga Mayu, 1970, kwana ɗaya kafin tashi. Dukkan 'yan tawagar sun mutu.