Open rocket speed question

[cessena12]

Hey, I am doing simulations for my loc bruiser. I have it going up on a j-400 and open rocket says that recovery device deployment at high speed. Is that because the delay is 16 seconds and it is coming down? So then all I would have to do is drill the delay charge less right?
Thanks.

 

[scsager]

Hey, I am doing simulations for my loc bruiser. I have it going up on a j-400 and open rocket says that recovery device deployment at high speed. Is that because the delay is 16 seconds and it is coming down? So then all I would have to do is drill the delay charge less right?
Thanks.

OR will show you exactly whats happening.

-Double click the simulation line.
-Choose "Plot flight" to see a graph of the flight.

The graph will give you an idea how soon after apogee the ejection charge fires.

-You can change the delay for a motor by using the drop-down, or just type in any number you want.

-Rerun the simulation with a new (shorter or longer as needed) delay until the ejection charge fires close to the apogee.

This will give you a good idea of how much you need to drill the delay when you actually build the motor.

 

[cessena12]

Thanks I really appreciate that. I just started messing with openrocket.

 

[cessena12]

Another question it says time until apogee 10 seconds but I need a delay of 9 seconds. That doesn't make any sense to me.

 

[Peter Olivola]

What's the propellant burn time on the J-400? If it's ~1 Sec. the delay of 9 secs. would be correct. Delay times are measured from propellant burnout, not ignition.

Another question it says time until apogee 10 seconds but I need a delay of 9 seconds. That doesn't make any sense to me.

 

[cessena12]

The burn time is 1.75 seconds.