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Re: Parachute Deploy Projects

Posted: Sat Feb 02, 2013 10:57 pm
by U.S. Water Rockets1
PTrockets wrote:Hello everyone,
The first project is very simple and also very popular. It's a airflap parachute deploy. (Without tommy timer_I will not present the tommy timer parachute deploy because I have one already). It's a mechanism that deploy the chute when the rocket lifts off.
It's actually a Tomy timer. One M in "Tomy". But yes, it is very popular, and easy to make and adapt.
The second project is the most popular and simple. It's called the NOAA parachute deployment system. It's a system that deploy the parachute after the apogee.
This is hit or miss. Most of the time the nose comes off when the rocket decelerates as it is still going up. Most of the remaining times the nose doesn't come off at all. It works so infrequently that when it does work it is quite satisfying.
The third project is almost like the previous. It's a NOAA deployment system with a ballon. The ballon helps the nosecone to jump of the rocket.
This is actually quite difficult to get right. The balloon is actually a really strong spring, so it will push the nose off unless you have something really strong holding it in place. We've used balloon springs in the past and the most useful are the long skinny ballons that they make balloon animals from. You make a long one and bend it in half to make a spring. It has a lot less force in this manner.
The fourth project it's a NOAA system too. It's a bit different because the nosecone is a tennis ball inserted in a toilet paper roll (the parachute is inside the roll and it's attached to the tennis ball_ and the ball is attached to the rocket).
This probably will come off a lot when the rocket decelerates. The extra weight will pull the nose off right after the air burst because the drag on the rocket body will slow the body down and the mass of the tennis ball will pull off the nose.
The fifth project is the most complicated of all. It's a baking soda and vinegar reaction chute deployment. The compressed air of the chemical reaction extends a serynge and realease the parachute. It's basead on the AntiGravity Corporation World Record Pop Bottle Rocket.
We have had a lot of success wit ha similar system, The hardest part is getting the timing right. The chemicals can take a long time to react and the time is unpredictable unless you remove variables. The ideal system will have little room for the gasses to expand into so there is little space for the gas to compress into. The other variable to look at is temperature, which can influence the speed of reaction. If you warm the chemicals, they will work much faster than when they are cold.

Keep us appraised of your progress developing these methods. It is always good to see people improving the old designs.

Re: Parachute Deploy Projects

Posted: Sun Feb 03, 2013 2:15 pm
by PTrockets
U.S. Water Rockets1 wrote: It's actually a Tomy timer. One M in "Tomy". But yes, it is very popular, and easy to make and adapt.
This is hit or miss. Most of the time the nose comes off when the rocket decelerates as it is still going up. Most of the remaining times the nose doesn't come off at all. It works so infrequently that when it does work it is quite satisfying.
This is actually quite difficult to get right. The balloon is actually a really strong spring, so it will push the nose off unless you have something really strong holding it in place. We've used balloon springs in the past and the most useful are the long skinny ballons that they make balloon animals from. You make a long one and bend it in half to make a spring. It has a lot less force in this manner.
This probably will come off a lot when the rocket decelerates. The extra weight will pull the nose off right after the air burst because the drag on the rocket body will slow the body down and the mass of the tennis ball will pull off the nose.
We have had a lot of success wit ha similar system, The hardest part is getting the timing right. The chemicals can take a long time to react and the time is unpredictable unless you remove variables. The ideal system will have little room for the gasses to expand into so there is little space for the gas to compress into. The other variable to look at is temperature, which can influence the speed of reaction. If you warm the chemicals, they will work much faster than when they are cold.
Keep us appraised of your progress developing these methods. It is always good to see people improving the old designs.
Hello U.S. Water Rockets,
Thanks a lot for your reply. Your information will be put to the test. Sorry the 'Tommy': I always mistake.
I will certainly publish the results. Lately, I have no time but as soon as I can, I'll start building.
Have a nice day and once again, TH:

PTrockets

Re: Parachute Deploy Projects

Posted: Sun Feb 10, 2013 2:47 pm
by PTrockets
Hi everyone!
I've good and bad news.
Good news:
I finished my NOAA rocket and my airfalp rocket (but still missing wings).
Bad news:
I haven't had time to make more rockets. My parachute ruptured and I have to make another. The NOAA parachute system with a balloon doesn't work.
I'll post photos soon.
Have a nice day,

PTrockets

Photos

Posted: Mon Feb 11, 2013 2:17 pm
by PTrockets
Here's some photos of the water rockets construction. Just missing the fins to be finished.

Bad news:
The vinegar and baking soda parachute system results but there is a small problem. The rubber band can't pull the parachute out of the nosecone.

Re: Parachute Deploy Projects

Posted: Sat Feb 16, 2013 11:30 pm
by U.S. Water Rockets1
Have you thought about using a cut section of bottle as a spring? We use this in our axial deploy system, and it works quite well.

http://www.uswaterrockets.com/construct ... torial.htm

Re: Parachute Deploy Projects

Posted: Sun Feb 17, 2013 2:58 pm
by PTrockets
U.S. Water Rockets1 wrote:Have you thought about using a cut section of bottle as a spring? We use this in our axial deploy system, and it works quite well.

http://www.uswaterrockets.com/construct ... torial.htm
Yes, I've saw it on your tutorial. But this case is not totally necessary. But I think I'll follow your advice. TH:

It Works!

Posted: Sun Feb 17, 2013 3:11 pm
by PTrockets
Everything went according to plan. The NOAA system worked wonderfully well.
I almost lost the rocket because the stupid wind took it to the woods. But half an hour later, I found the rocket hanging on a branch.
Luckily I didn't put the camera in the rocket.
My advice: NEVER LAUNCH A WATER ROCKET (especially with parachute) IN WINDY DAYS.
Greetings,

PTrockets

[youtube][/youtube]

Re: Parachute Deploy Projects

Posted: Mon Feb 18, 2013 12:04 am
by Asupremeflight
Congrats on a successful launch. Yea it doesn't take much wind to send them into the trees. You could try to speed up the decent a little by cutting a hole in the parachute. Or you could just tie the strings closed about half way so it does not open all the way. It will still bring it down safely just a little faster. That way is the better choice because on the not so windy days you can just open it up again for a full deploy.

Were you able to retrieve the rocket or is it up too high?

Re: Parachute Deploy Projects

Posted: Mon Feb 18, 2013 8:00 am
by PTrockets
Asupremeflight wrote:Congrats on a successful launch. Yea it doesn't take much wind to send them into the trees. You could try to speed up the decent a little by cutting a hole in the parachute. Or you could just tie the strings closed about half way so it does not open all the way. It will still bring it down safely just a little faster. That way is the better choice because on the not so windy days you can just open it up again for a full deploy.

Were you able to retrieve the rocket or is it up too high?
Hi Asupremeflight,
First of all, thanks for reply.
The rocket flew more than 100 meters, I'm sure. I have altimeter so I can not say for sure.
I was able recover the rocket half hour later. I found it more than 200 meters from the launch site. The water rocket was resting on a branch hanging by the parachute.

PTrockets

Re: Parachute Deploy Projects

Posted: Tue Dec 10, 2013 1:54 am
by lfugazi444
Last year the kids on my teams did a lot of the # 4's. We used all kinds of different balls the best was a wiful ball it was lite but had a enough weight to pull the parachute out. Some of the kids used a 32oz cup in side of a cut 2 liter taped to the engine side of the rocket. The bottom of the 32oz was cut just a little under sized to hold the ball then the cut 2 liter placed over the top to keep it in place. the longest hang time on a no wind day was 5 mins. We lost our best rocket on a windy day. most of our parachute are around 50 inches.

Re: Parachute Deploy Projects

Posted: Fri Jul 04, 2014 9:28 am
by heath loxton
my NOAA system gives us this launch quality!

https://www.youtube.com/upload


Cheers, Heath. :)

Re: Parachute Deploy Projects

Posted: Fri Jul 04, 2014 9:35 am
by heath loxton
sorry wrong link take 2!

[youtube][/youtube]