We have to adjust rod angle in 5degrees. Isn't any way for the problem? I work the problem for 2 weeks
First of all, I do not believe there's any weathercocking here; speed off the rod is extremely high.
Let's look at some numbers.
According to the sim, maximum vertical velocity of rocket = ~1100 fps at motor burnout
Assuming 5 degree flight angle, we can predict lateral velocity from a basic trig calculation: maximum lateral velocity = 11000 * tan(5 degrees) = 96 fps
The sim says:
That shows about 140 fps maximum lateral velocity. Why the difference? My suspicion is wind. The sim is set for ~5 mph wind. I believe that the rod at +5 degrees is
with the wind, which means the wind is adding to the lateral velocity over the course of the flight.
So I tried changing the rod angle to -5 degrees, and look what happens:
Maximum lateral velocity is now down to about 84 fps, and deployment is around 47 fps (and the warning goes away).
What do we learn?
1) Launching the rocket at an angle ensures that it will have some lateral velocity at apogee.
2) Launching into the wind will offset that somewhat, provided that the rocket does not weathercock (again, if you use the very long long rail and high-thrust motor you have in the sim then weathercocking should not be an issue)
3) Your parachute at apogee needs to be able to handle it. Build accordingly.