Fireflash's fictional shielding and cockpit placement

Thunderbirds' Fireflash supplies a fictional example for discussing nuclear-aircraft design. Its shielding is described as lasting only three hours before passengers would be exposed, with replacement needed after each flight. That premise is challenged because radiation shielding is not normally treated as a barrier with such a simple expiry time; another participant suggests neutron activation as a possible complication. The cockpit's position at the top of the tail fin raises a separate concern about what pilots can see during landing. The exchange criticizes the fictional arrangements without presenting Fireflash as an actual aircraft design.