Rockets in a transfered world not working

In a transfered world. rockets are not always firing when elytra are engaged. This occurs during taking off from a one block height and higher. Flew to the end city and rockets would not propel over the void at all times. They will fire if I cursor to the ground but it appears your code while in flight or taking off with elytra fully engaged doesn't always register to be able to propel the player.