ðə pɹˈɑːpɚɹ ˌɑːpɚɹˈeɪʃən ʌvðɪ ˈɛsˌaɪvˌiːbˈiː θˈɜːd stˈeɪdʒ ʌvðə ɹˈɑːkɪt wʌz kɹˈuːʃəl, ænd ɪnðə lˈæst ʌŋkɹˈuːd tˈɛst, ɪt hæd fˈeɪld tə ɹˌiːɪɡnˈaɪt fɔːɹ ðɪs bˈɜːn.
The proper operation of the S-IVB third stage of the rocket was crucial, and in the last uncrewed test, it had failed to reignite for this burn.