Mountain Drew Adventure

Watch the video of our adventure by clicking here

Final Blog Post

After five days of bottle rocket launching, the process is finally over. Our rocket has been through more than we ever thought was possible. We learned a lot about physics through this project. I learned a lot about aerodynamics, design, center of pressure, center of mass, and using resources conservatively. Our first bottle got stuck in a tree after our second launch, so we had to deal with starting over from scratch as well as redesigning our rocket when certain aspects of it failed. I learned to observe closely and troubleshoot the problems that our bottle experienced. This was necessary in order to keep increasing the time that our bottle was in the air, as well as be successful in our endeavor. The details to our 5 days will be listed below:

Day 1) Our bottle rocket consisted of a 2 liter bottle, filled with one cup of water and pumped up to 40 psi. Our second launch came with the most success, about 3 seconds in the air.

Day 2) Our bottle rocket got upgraded on day two. We added three cardboard fins, duct-taped for aerodynamics, which were hot-glued onto the bottom of the rocket. We also installed a small piece of wood to the top of the bottle in order to create a top heavy rocket. This, we discovered, would make the Center of Mass higher than the Center of Pressure and make our rocket travel higher and in a more controlled way. Our first launch lasted about 5 seconds. This is an upgrade from day 1. Our second launch got stuck in the tree and we were forced to start from scratch.

Day 3) Our new bottle rocket was created to look exactly like the previous rocket. We added a paper cone, to make our rocket more aerodynamic. Under the cone, we attached a parachute, a plastic bag that was attached to our rocket with string. The parachute was unsuccessful in deploying properly. We also found out that the paper, no matter the shape it was in, only distracted from the time the rocket was in the air. After figuring this out, we took off the cone and added two cups of water and pumped our rocket up to 60 psi, gaining a successful 7.7 seconds in the air.

Day 4) On day 4 we installed a new and improved cone to our rocket. The cone consisted of the bottom of another 2 liter bottle. Duct taped heavily for aerodynamics and attached to a small rock for a higher CM. Under the cone, we attached a much larger plastic bag (a garbage bag to be exact) to the rocket. This parachute was much more successful. When it deployed, it picked up a lot of wind and slowed down our rocket's decent. Our new cone, however was in consistent in falling off of our rocket when we needed it to. Therefore, we had a bunch of successful and unsuccessful launches. Our best timed for 8.8 seconds.

Day 5) Our last modification consisted of a new cone. Our cone was both heavy and aerodynamic. It was a small traffic cone, which fitted exactly on our bottle. The cone was big enough so that our parachute could fit securely under our cone and yet, be loose enough so that it could deploy easily in mid-air. We attached our cone to our rocket so after it fell off it would still be attached. After many disappointing launches, we timed in at 9.5 seconds, just short of our 10 second goal.

"Post Lab"

What worked best was a semi-heavy traffic cone as a bottle rocket cone. The parachute worked best when it was extremely large so that it could catch more wind and slow down our rocket even more. The smaller the strings that attached the rocket to the parachute, the better. The longer the strings, the more likely they were to get tangled when confined in the cone. Our fins worked very well. They kept the rocket from twisting and spinning uncontrollably. We also learned that the more water there is in the rocket, the higher the rocket will fly when launched. We also made sure that we pumped the rocket to about 60-80 psi to ensure that it launched with maximum efficiency. Thus concludes our conclusion of our bottle rocket adventure. We wouldn't do anything different if we had to do it again.

Last Launch Day

This final launch day was a bit disappointing, to say the least. We found that the most crucial part to the bottle rocket process was the parachute deployment: it couldn't come out too early or too late. Most of it, I think, is based on luck and wind. No one really knew how to guarantee a successful parachute deployment/nose cone coming off at the right time or even at all. The nose cone and parachute are the most crucial elements to air time.

What we did was remove and reattach the fins onto our rocket for extra durability and to make sure it could sustain multiple launches. Then came the hard part. We had a cone to use as the nose of the rocket, hoping it would be more aerodynamic and better looking than the top of another bottle. Our last problems with the parachute was it getting tangled in the string. Our solution to this was to shorten the string length and to hide the parachute in the cone in such a way that the string would not tangle. Andy found a way to do that. However, a very unfortunate incident involving an insufficient duct tape supply rendered us incapable of successfully securing the nose cone to the rocket, which was a regulation in the rules.

With high hopes, we set off to our final launching period. During this series of launches, getting air wasn't a problem in our case, it was the parachute part. One launch had an airtime of 9.5 seconds, a mere .5 points away from extra credit. On the next one, we got an amazing 12 seconds! But because of the lack of duct tape, our cone came off, deeming the launch "disqualified." During the next launch, our rocket gained a lot of air, but the parachute didnt deploy, and it was pretty much destroyed in the ensuing crash. The final launch after a hasty masking tape repair was disappointing as well. In the end, it was a very enjoyable and educational experience. We tried our best out there, after all. Also we needed more tape.

Launch Day 4

After a successful pair of launches last time out, our group set out to further improve our rocket. We learned from our last launches that the cone was an essential part of our rocket and that the cone needed to be heavy and durable, in order for our rocket to launch further. Thus, for this time out, we decided to construct a heavier duty cone, by cutting off the top of a separate bottle and attaching it to our launching bottle. Though our bottle was heavily damaged after our last launch, we were able to salvage the bottle itself. By cutting off the top of the other bottle and heavily ducktaping the top, to promote weight and durability, we were able to produce a cone that was sturdy and that added weight to our bottle. We also added a rock into our cone, in order to add more weight to our bottle. We also decided to construct a larger and more durable parachute for these launches, as we realized that our previous parachute was far too small and did not catch enough air to slow down our bottle.

For our first launch, we were able to successfully launch our bottle into the air without a hitch. At the top of its ascent, the bottle lost velocity and our cone came off, allowing for our parachute to successfully deploy on our bottle's descent. The heavier cone allowed for our bottle to travel very high into the air, and our sturdier parachute increased the hang time of our bottle. We were able to achieve an overall air time of 8.8 seconds, before our bottle was caught by the wind. This launch could be considered a complete success as all of our changes worked out exactly as planned.

Our second and third launch were very similar in that they had the right idea, but they both failed to work out as planned. We added a rock to our cone, thus increasing the weight of our overall bottle. For these launches, our bottle launched further than before and thus, seemed successful at first. However, though our cone successfully fell off at the top of the bottle's ascent, our parachute was tangled in both of these launches and failed to deploy properly. Although our parachute did not deploy as planned, all of the other aspects of our launch worked out as planned, which led us to believe that our last major hurdle is having our parachute deploy consistently.

We believe that if we make a few more minor adjustments to our bottle, that we will consistently hit 10 seconds in our air times for our launches. By elongating our bottle, adjusting our parachute, adding more pressure into the bottle and possibly adding more water into our launch, we can improve the initial launch itself and the hang time of the bottle as it descends. Our launches today were a success and gave us valuable information moving forward in our launches.

Day 3

Today was Day 3 for our bottle rocket experiment. Today we started from scratch, after losing our rocket to the Midkiff Tree on Day 2. The new bottle we modified with 3 triangular fins, much like the fins we used on Day 2. The fins were made out of cardboard and were completely covered with duct tape. The fins were then "hot glued" onto the bottom of the rocket and reinforced with duct tape. To place the center of mass higher than the center of pressure, we added a moderately heavy piece of wood to the top of our rocket. This piece of wood was duct taped on very securely so that it would not fall off in mid-flight. Our additions to today's model were the cone and parachute. Our cone, we wanted to make extremely light, so that it would fall off at the peak of the rocket's flight. So we constructed a cone shaped object with a few pieces of paper and placed it on the top of a bottle. For our parachute, we connected a plastic bag to the bottle with a long piece of string. We tucked the bag under the cone after folding it up neatly and winding the string around the bag. This completed our new model.

For Launch 1, our cone stayed securely on the rocket for its entire flight. This was a failure, because the parachute could not escape the cone and inflate to slow down the rockets descend. The rocket stayed in the air for only 3.72 seconds.

For Launch 2, we made sure that our cone was on very loosely. At the peak of its launch, the rocket's cone fell off and the parachute deployed. The problem was that the parachute didn't inflate at all, so the parachute was a failure. For our next launch day we are going to make adjustments on the model of the parachute. The rocket stayed in the air for 4.86 seconds.

For Launch 3, took off the cone and the parachute to see if our cone was keeping the rocket from traveling as high as it did on day 2. The launch was extremely successful. It stayed in the air for 7.72 seconds. We concluded that the cone needs to be heavy, to ensure that it launches as high as possible. We will make appropriate modifications for our next launch.

Launch Day 2

Following up on that video my good friend Max just posted, launch day 2 was indeed a more successful and less painful day for us. We discovered that modifications would allow our rocket to be more aerodynamic while in the air. For example, a center of gravity that is higher than the center of pressure would improve the rocket's performance by allowing it to fly straight and not flip around. We also learned that fins would keep the rocket from spinning on its axis, which is a good thing because that will help keep it in the air for a longer period of time. During launch, our rocket was attached with 3 fins and a payload (piece of wood). It shot very high and fast, higher than any other rocket I'd seen so far. The only thing was, it got stuck in a tree. We could probably improve on the modifications by having a better payload on the tip and a parachute for sustained air time.

Here is a quick video containing our second launch of day 2. Our rocket contains a few modifications including 3 cardboard fins and a ghetto nozzle (piece of wood)