▁ 1 8   mm ▁mot ors ▁have ▁a ▁maximum ▁thrust ▁between ▁ 1 2 . 1 5 ▁and ▁ 1 2 . 7 5 ▁N , ▁a ▁total ▁imp ulse ▁between ▁ 4 . 2 ▁and ▁ 4 . 3 5 ▁N · s , ▁and ▁a ▁burn ▁time ▁between ▁ 0 . 8 5 ▁and ▁ 1 ▁second . ▁The ▁C ▁class ▁ 1 8 mm ▁mot ors ▁have ▁a ▁maximum ▁thrust ▁from ▁ 1 4 ▁– ▁ 1 4 . 1 5 ▁N , ▁a ▁total ▁imp ulse ▁between ▁ 8 . 8 ▁and ▁ 9 ▁N · s , ▁and ▁a ▁burn ▁time ▁between ▁ 1 . 8 5 ▁and ▁ 2 ▁seconds . ▁ ▁There ▁are ▁also ▁ 3 ▁classes ▁included ▁in ▁Est es ▁large ▁( 2 4   mm ▁diameter ) ▁ro cket ▁mot ors : ▁C , ▁D , ▁and ▁E . ▁The ▁C ▁class ▁ 2 4   mm ▁mot ors ▁have ▁a ▁maximum ▁thrust ▁between ▁ 2 1 . 6 ▁and ▁ 2 1 . 7 5 ▁N , ▁a ▁total ▁imp ulse ▁of ▁between ▁ 8 . 8 ▁and ▁ 9 ▁N · s , ▁and ▁a ▁burn ▁time ▁between ▁ 0 . 8 ▁and ▁ 0 . 8 5 ▁seconds . ▁The ▁D ▁class ▁ 2 4   mm ▁mot ors ▁have ▁a ▁maximum ▁thrust ▁between ▁ 2 9 . 7 ▁and ▁ 2 9 . 8 ▁N , ▁a ▁total ▁imp ulse ▁between ▁ 1 6 . 7 ▁and ▁ 1