Fast descents?

[jraice]

My 6" dual deploy bird is simed to fall 60-70FPS depending on final weight. Is that to fast for a fall on a drogue? The rocket is very lightly glassed, I would consider it kraft but it is a little stronger from the glass.

 

[daveyfire]

Geeze man, you've asked this question a thousand times in a thousand threads. You'll be fine at 70 fps. I know a guy who brings in his rockets ballistic from apogee, then lets them do the drogue/main thing starting at about 4000 feet. Suck it up and go fly the freakin' rocket!

 

[edwardw]

How did you sim it? Rocksim? Final rocket weight and then a parachute sized for that FPS?

Also, your profile says your an L2 flier. Most L2 fliers I know gain a lot of basic and advanced rocketry knowledge as they climb the certification ladder and fly a lot. I know I gained a lot going from LPR to HPR. You learn how rockets fly and get a feel for them. How long have you been flying rockets?

Edward

 

[jraice]

I have been flying estes for a long time, mid power for about 4 years and highpower for 2 years. I have not done a lot of fast descent dual deploy rockets, so I am getting knowlagible now.

 

[Ryan S.]

Originally posted by daveyfire
Geeze man, you've asked this question a thousand times in a thousand threads. You'll be fine at 70 fps. I know a guy who brings in his rockets ballistic from apogee, then lets them do the drogue/main thing starting at about 4000 feet. Suck it up and go fly the freakin' rocket!

I concur, the rocket will be fine, you need to fly to find out what is going to happen.

 

[jraice]

I used the rocketryonline.com simulation for descent rates.

 

[lalligood]

Originally posted by daveyfire
Geeze man, you've asked this question a thousand times in a thousand threads. You'll be fine at 70 fps. I know a guy who brings in his rockets ballistic from apogee, then lets them do the drogue/main thing starting at about 4000 feet. Suck it up and go fly the freakin' rocket!

I agree with this statement too. Quit talkin' & get flyin'! Worst thing that can happen is that you have an experience that you learn from (maybe a little, maybe a lot)...and maybe rebuild some/part/all of your rocket. It happens...

They wouldn't call it "rocket science" if it was easy!

 

[DynaSoar]

Originally posted by jraice
My 6" dual deploy bird is simed to fall 60-70FPS depending on final weight. Is that to fast for a fall on a drogue? The rocket is very lightly glassed, I would consider it kraft but it is a little stronger from the glass.

That's a fine speed, as long as your drogue can keep it there, and as long as your main can handle opening at that speed. Descent speed on a drogue (or for that matter without) is really fairly irrelevant except for the ability of your main to handle opening at that speed. Or, of course, to the ability of your rocket to handle landing at that speed should the main not deploy.