Air Trajectory B/C

[jdemaris]

I see a lot of talk about ping-pong balls and PVC pipe. I don't see anyone stating what sort of PVC pipe or what sort of ping-pong ball. Maybe I missed it somewhere in these discussions? PVC does not have just one ID. It is the OD that is the constant. So, "1 1/2" PVC is always 1.9" on the outside diameter, but the inside-diameter differs depending on if the pipe is schedule 30, 40, 80, etc. And with ping-pong (table tennis) balls - there are two standard sizes. The old standard is smaller then the new one. Also, on the subject of air-defection- there are special outdoor "practice" balls that are heavier and designed to help off-set air currents when used outdoors.

On the subject of the "Science Olympiad" in general. This is my first experience with it. I hear a lot about "innovation." Looks to me like much has been done to remove room for innovation. I also wonder why it takes so long to get a rules-clarification considering there is only one place to do it.


1 ½” schedule 30 – 1.59” ID and 1.9” OD
1 ½” schedule 40 – 1.65” ID and 1.9” OD
1 ½” schedule 80 – 1.476” ID and 1.9” OD

[reed303]

I see a lot of talk about ping-pong balls and PVC pipe. I don't see anyone stating what sort of PVC pipe or what sort of ping-pong ball. Maybe I missed it somewhere in these discussions? PVC does not have just one ID. It is the OD that is the constant. So, "1 1/2" PVC is always 1.9" on the outside diameter, but the inside-diameter differs depending on if the pipe is schedule 30, 40, 80, etc. And with ping-pong (table tennis) balls - there are two standard sizes. The old standard is smaller then the new one. Also, on the subject of air-defection- there are special outdoor "practice" balls that are heavier and designed to help off-set air currents when used outdoors.

On the subject of the "Science Olympiad" in general. This is my first experience with it. I hear a lot about "innovation." Looks to me like much has been done to remove room for innovation. I also wonder why it takes so long to get a rules-clarification considering there is only one place to do it.


1 ½” schedule 30 – 1.59” ID and 1.9” OD
1 ½” schedule 40 – 1.65” ID and 1.9” OD
1 ½” schedule 80 – 1.476” ID and 1.9” OD

ISTM that researching what works, and what does not, is part of the point of SO construction events. Otherwise you could just buy a kit and glue it together.

Re innovation, just wait til you see what wildly different approaches your competitors will take to the same event.

Good Luck.........

[chalker]

... I hear a lot about "innovation." Looks to me like much has been done to remove room for innovation. I also wonder why it takes so long to get a rules-clarification considering there is only one place to do it.....

Regarding innovation, there is still plenty of room for it. There is a very difficult balance of many variables we have to strike as rules writers, which include things such as:
-Making sure 'rich' teams don't have a significant advantage over 'poor' teams due to being able to buy certain things
-Making sure experienced teams that competed in prior years don't have a significant advantage over 'newbie' teams
-Making sure the ~400 event supervisors for each event this year are able to objectively and efficiently judge teams within the time and space constraints they face
-Making sure events have a low barrier to entry (for the tens of thousands of students who are new this year), but still complicated enough to differentiate the 60 best teams that will compete at Nationals
-Making sure competitors have an opportunity to learn something and be challenged in the process of preparing for an event
- etc. etc. etc.
Having been involved in this for decades, I can assure you every year there are amazing things competitors do that are incredibly innovative. In Air Trajectory alone, I saw numerous very novel designs last year and expect the same this year.

Regarding the delay for rules clarification responses, I'll point to my numerous prior statements on this process. The bottom line is SO is 99% volunteer run, and at the National level has a lot of committees engaged, whose members all have day jobs. We handle thousands of FAQ/clarification requests every year, and each one needs to go through a process the usually involves several sets of eyes looking and commenting on them. This week alone I personally saw ~80 questions for Physics related events. Some of them went through the process within a few days and were answered pretty quickly, others will take longer at we discuss amongst the committee members.

[jdemaris]

No offense intended here but it sounds kind of silly to me.

If real science in the real world had to limit itself to these two two factors you listed - hardly anything would get done.
It sounds like part of the equation is dumbing things down so all can participate. This kind of thinking reminds me why my newest children are being home-schooled.

-Making sure 'rich' teams don't have a significant advantage over 'poor' teams due to being able to buy certain things
-Making sure experienced teams that competed in prior years don't have a significant advantage over 'newbie' teams

[XJcwolfyX]

Sounds like you have a bad attitude. This competition is a place for students to engage in STEM related events and allow them to 1. Be with people who share common interests and 2. Introduce and expose students to the world of science and engineering. Nothing is an exact science here. These are adolescents competing, some as young as 11. If you want exact, professional science, that does not occur at middle school and high school levels and only is at extremely advanced levels of education. It's a shame you don't want your children to participate in this "dumbed down" competition.

[jdemaris]

RE your comment . . " It's a shame you don't want your children to participate in this "dumbed down" competition."

I did not say anything to indicate I don't want my children to "participate." Looks like we have word-connotation-problems here again.
I stated that my last child is home-schooled. That has nothing to do with 'not participating" in the Science Olympiad. He is involved and I am a coach.

[JonB]

RE your comment . . " It's a shame you don't want your children to participate in this "dumbed down" competition."

I did not say anything to indicate I don't want my children to "participate." Looks like we have word-connotation-problems here again.
I stated that my last child is home-schooled. That has nothing to do with 'not participating" in the Science Olympiad. He is involved and I am a coach.

jdmaris, do you have a specific question related to air trajectory? Looking at your post from yesterday, you are correct that many do not post specific sizes of PVC or table tennis balls. In general, many people do not share their specific designs.

Let's all try to stay specifically on the topic of air trajectory and nothing else in this thread.

[jdemaris]

At the incipient stage - I came to this forum (not this specific thread) with one question. There was no emotion attached to it. Just a fact-based question. In response I got several emotion-loaded responses here and a few were nasty. Since then - my initial question got answered, with logic, at the official rules clarification area at the Olympiad website. I do have several more questions but will not post them here. A little bit too much emotion and too little logic in some of the replies. And note - I say that with no intention of degrading those that do not act in that manner.

In reference to my post about ping-pong ball and PVC pipe IDs? I added the info after reading many posts that made it clear that some here do not realize that there is no standard ID for PVC water-pipe. It varies by "schedule" which is wall thickness. Only the OD is a constant. Same with my comment about there being two standards used for official ping-pong balls. Nothing to do with plan-secrets. Just common knowledge to those that have worked in trades like plumbing.

[XJcwolfyX]

At the incipient stage - I came to this forum (not this specific thread) with one question. There was no emotion attached to it. Just a fact-based question. In response I got several emotion-loaded responses here and a few were nasty. Since then - my initial question got answered, with logic, at the official rules clarification area at the Olympiad website. I do have several more questions but will not post them here. A little bit too much emotion and too little logic in some of the replies. And note - I say that with no intention of degrading those that do not act in that manner.

In reference to my post about ping-pong ball and PVC pipe IDs? I added the info after reading many posts that made it clear that some here do not realize that there is no standard ID for PVC water-pipe. It varies by "schedule" which is wall thickness. Only the OD is a constant. Same with my comment about there being two standards used for official ping-pong balls. Nothing to do with plan-secrets. Just common knowledge to those that have worked in trades like plumbing.

What is your question exactly about the PVC pipes and ping pong balls?

[JonB]

At the incipient stage - I came to this forum (not this specific thread) with one question. There was no emotion attached to it. Just a fact-based question. In response I got several emotion-loaded responses here and a few were nasty. Since then - my initial question got answered, with logic, at the official rules clarification area at the Olympiad website. I do have several more questions but will not post them here. A little bit too much emotion and too little logic in some of the replies. And note - I say that with no intention of degrading those that do not act in that manner.

In reference to my post about ping-pong ball and PVC pipe IDs? I added the info after reading many posts that made it clear that some here do not realize that there is no standard ID for PVC water-pipe. It varies by "schedule" which is wall thickness. Only the OD is a constant. Same with my comment about there being two standards used for official ping-pong balls. Nothing to do with plan-secrets. Just common knowledge to those that have worked in trades like plumbing.

What is your question exactly about the PVC pipes and ping pong balls?

jdemaris, I am glad your question was answered via the website.

XJcwolfyX, he just posted information about PVC to help everyone out.