ONE SMALL MISSTEP FOR MANKIND

American aerospace executives worried about competition from other countries seeking lucrative commercial launching contracts can sleep more soundly tonight. A German-designed satellite, built in Russia and launched by Japan, nosedived into the Pacific today after circling the Earth two or three times. German and Japanese space agency officials are not sure what happened to the $60 million "Express" satellite, which was launched Sunday night from the Kagoshima Space Center, 620 miles southwest of Tokyo. The Express, launched to help in research on gravity and re-entry technology, seems to have provided an unintended lesson for its designers.