See also this image from the article. The design of the Aldebaran is a giant flying boat, with air intakes in the wings to help create the nuclear exhaust exiting the reaction chamber nozzle.
Here's the famous XKCD radiation dosage chart for scale: https://xkcd.com/radiation/ . The highest scale in the chart, the yellow boxes, represents 50 Sieverts, of the dosage received from standing next to the Chernobyl core for ten minutes just after meltdown. A conservative estimate is that one launch on this thing would expose the crew to 5000 Sieverts, or 100 Chernobyls worth. Furthermore, we've sen how simple atmospheric nuclear testing irradiated the entire planet for half a century (see the Kodak film story and low-background steel), any prolonged use of this thing would have caused cancer rates to (ahem) skyrocket worldwide due to distribution of nuclear fallout into the atmosphere.
Let's not romanticize stupid ideas. Leave this one in the dustbin of history.
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