Parachutes ejecting during event?

[Robsrockettime]

Do you MAKE SURE the chutes come out all the way, or still knowing they're loose inside the tubes would you believe it would still come out from just opening/separating? Or is it best to know that it is pulled out. I guess probably the latter but just wondering what others experience is.

Just curious of everyone's logic.

Again referring to the videos below. The main chute is not pulled out by the nose cone but is very loosely packed inside the body tube. Being the main chute I can understand probably want it to come out.

Drogue test


Main chute test

 

[David Schwantz]

Top video is perfect. Chute IS pulled out by NC and the shock cord is not jerked to the end. Bottom video is not enough BP to get the chute pulled out. IMHO I would up the BP charge on that video.

 

[3stoogesrocketry]

That main setup will cause a hard landing, I know from experience. With the tube attached to the cone, you are compressing the chute and contents into the nose cone, the opposite way it should go. Either the main needs to be attached essentially to the Ebay , or the main tube needs to be attached to the Ebay and shoot the cone off.

 

[T-Rex]

I've watched the videos several times and I am confused about something. It looks to me the rocket separates the same in both videos. I thought one is drogue and one is main? Shouldn't main and drogue come from different places? And yes, the 'chute should be ejected from the tube. You do no want to rely on the wind to pull it free.

 

[David Schwantz]

On the bottom video, main chute, you can clearly see the av bay still in the booster. On top video, drogue chute, the av bay stays with the payload section.

 

[Robsrockettime]

Top video is perfect. Chute IS pulled out by NC and the shock cord is not jerked to the end. Bottom video is not enough BP to get the chute pulled out. IMHO I would up the BP charge on that video.

Okay. I’m at 1.4g ffffg at this point.

1.3g Drogue (shorter internal body tube ~18in)
1.4g Main. ~20in

That main setup will cause a hard landing, I know from experience. With the tube attached to the cone, you are compressing the chute and contents into the nose cone, the opposite way it should go. Either the main needs to be attached essentially to the Ebay , or the main tube needs to be attached to the Ebay and shoot the cone off.

I do have the “short” end of the shock cord attached to the NC. I was thinking of switching the short side to the eBay would be the best option. After I saw these results as well. I didn’t give thought to attaching directly to the eBay.. that’s would for sure pull it free.

I've watched the videos several times and I am confused about something. It looks to me the rocket separates the same in both videos. I thought one is drogue and one is main? Shouldn't main and drogue come from different places? And yes, the 'chute should be ejected from the tube. You do no want to rely on the wind to pull it free.

The angle doesn’t really help, but they are separated by an eBay. Thx for the advice.

I was thinking it might get pulled out by the separated parts but I suppose that’s not as reliable as just making sure it comes out.

 

[Robsrockettime]

Thanks for the confirmation guys! You guys are great!

Especially on the”easy” questions. It’s great to have a place to go to get help and answers from much more experienced individuals!

 

[bobbyg23]

I think the confusion comes from the main assy. Typically the top tube is fastened to the ebay and the charge blows off the nosecone and pushes the chute out of the tube. I have never seen where the top tube is fastened to the nonecone and the entire assembly is blown off the avbay

 

[Robsrockettime]

I think the confusion comes from the main assy. Typically the top tube is fastened to the ebay and the charge blows off the nosecone and pushes the chute out of the tube. I have never seen where the top tube is fastened to the nonecone and the entire assembly is blown off the avbay

Yeah the top BT is attached to the NC. I had been contemplating which side to separate as well. I see it as a horse a piece, not sure if it makes much of a difference. Unless it comes down to ease of chute deployment.

 

[3stoogesrocketry]

Yeah the top BT is attached to the NC. I had been contemplating which side to separate as well. I see it as a horse a piece, not sure if it makes much of a difference. Unless it comes down to ease of chute deployment.

Unless you can run your ejection charge above your chute (mounted to the nose cone) blowing it towards the ebay , forcing the chute out , you should always pop the top. Another point of interest , as the rockets get bigger , they get exponentially heavier. Think of all the extra mass (even if it's only a pound or two) trying to force the main out when the drogue deploys. Think of the main as a slide hammer. The heavier the hammer , the more force trying to separate the rocket. Even a loose main parachute can knock the nose cone off at drogue deployment. Then when it comes to max velocity flights , having two joints withing a few inches of each other will make the rocket bend / flex alot more.

 

[rcktnut]

To me looks like the drogue chute could be closer to the payload section, mine are. Definitely unconventional deployment as far as the main goes. Popping the nose cone would be more reliable/certain than method shown.

BTW what city in WI?

 

[Robsrockettime]

Unless you can run your ejection charge above your chute (mounted to the nose cone) blowing it towards the ebay , forcing the chute out , you should always pop the top. Another point of interest , as the rockets get bigger , they get exponentially heavier. Think of all the extra mass (even if it's only a pound or two) trying to force the main out when the drogue deploys. Think of the main as a slide hammer. The heavier the hammer , the more force trying to separate the rocket. Even a loose main parachute can knock the nose cone off at drogue deployment. Then when it comes to max velocity flights , having two joints withing a few inches of each other will make the rocket bend / flex alot more.

To me looks like the drogue chute could be closer to the payload section, mine are. Definitely unconventional deployment as far as the main goes. Popping the nose cone would be more reliable/certain than method shown.

BTW what city in WI?

Alright… thanks for the insight.. I can understand that when the separations are close together, that would give the rocket more flex in that spot. I have kinda witnessed it actually already.
And another good point, when the Drogue deploys the shock from that drives the main chute against the Av bay BH. Which is where I now have the shear pins. Currently, the nose cone and BT are screwed together. I’ll switch this before my flight this coming weekend.

Rcktnut I’m in Green Bay

I knew it wasn’t a typical setup for deployment.

This is the biggest rocket I’ve built to date. So it’s definitely new territory for me. Thanks for bouncing off my ideas to what works for others. Big help vs the trial an error I’m used too

 

[rcktnut]

I will PM you tomorrow, got to go for now. Our club has a launch field just East of Fond Du Lac, 10,000ft waiver although not available year round like Bong. Can give you some info if interested. Closer to home for you and nice open fields when crops are off!!

 

[Robsrockettime]

Sounds great rcktnut! Thanks