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"The importance of a reliable and effective heat shield cannot be overstated. The availability of a proper heat shield was absolutely critical for the safe return of all the Apollo crews. NASA's admission that the agency cannot now recreate the thermal shield of a return module is absolutely astounding. Such an admission could only be compared to an inconceivable statement that, for example, American military officials admit that after using armoured steel in their tanks during World War II, some 40 years later they don't have the technology at hand to develop armoured steel and have great difficulty in reproducing such steel despite the previous experience during the war." […]