What I expected to happen was...:
Firework_rocket should travel with model pointing in up in y-axis with high speed.

What actually happened was...:
Model of Firework_rocket is displaying in wrong direction when flying towards destination on y-axis. Firework_rocket is also traveling with reduced speed 

Steps to Reproduce:
1. In "Java 1.16 Pre-release 2" ,  set a dispenser pointing up to y-axis
2. Insert a Firework_rocket with flight duration above 0 into dispenser
3. Apply a red stone signal to the dispenser

4. Visually examine the model of Firework_rocket fired from the dispenser facing y-axis

5. Repeat the process in "java version 1.14.4" and compare the results.