Throwing Frisbees off the Upper Deck...

Yjacket82

Georgia Tech Fan
Messages
78
Location
Greenville, SC
You "kids" were so nice. (tic) I remember fish and rotten eggs for Notre Dame in 77 or 78.

There's a reason the students don't sit behind the opposing team anymore, especially within range of the upper decks. We also may have gotten banned from TV (I know we got in trouble) for a while for the "bullsh!t" cheer to critique the officials. Today the throwing thing would be frowned on more and the swearing is more typical. I guess times do change.

I remember the fish for ND. I am not proud to say this today, but I remember that black garbage bag of fish hanging outside my dorm room (Smith) for about a week. It was hot the day of the game and ND had fans blowing on them. Of course, those became the targets. Then there was the Rat group stealing the Auburn Tiger tail... I think we would be put under the jail for stuff like that today.
 

Blumpkin Souffle

Bidly Biddington III
Messages
1,367
Yea, I remember what a disaster the seat cushion thing was - covered the North end zone...

Even a little cheapo Frisbee would crack a skull when it's coming straight down from over a hundred feet...
Bro do you even physics?

Friction will gradually diminish the rotational inertia until it no longer has enough gyroscopic force to remain upright.
 

bartoma

Jolly Good Fellow
Messages
357
Location
Herndon, VA
Bro do you even physics?

Friction will gradually diminish the rotational inertia until it no longer has enough gyroscopic force to remain upright.

Umm, yea - prior to the BEE from GT and MSEE from VT - Bro... I also English... and write...

Do you do aerodynamics? A Frisbee, launched horizontally from 100-200 feet AGL (or whatever), will continue to travel horizontally some distance - and as you say, it will, at some point, no longer remain upright... But after this happens, it will fall on its edge in a near-vertical path towards the fore-mentioned band member's skull... And that's not even taking into account the likelihood that the student launching said Frisbee is throwing it deliberately at an upward and tilted angle to accentuate its subsequent dive to the ground...

So, taking into account that drag on a vertically-falling Frisbee is likely insignificant, and assuming it's falling from, say, 150 feet, it gonna be traveling at something on the order of 60 mph... And is this Frisbee weighs something like 90 grams (roughly 3 ounces), this results in an impact of approximately 40 joules - well within the range (14-60 joules) that can cause a fracture to the human skull...

Sources:

http://www.angio.net/personal/climb/speed

http://www.omicsonline.com/open-access/2090-2697/2090-2697-2-108.pdf?aid=15101
 

GTNavyNuke

Helluva Engineer
Featured Member
Messages
10,004
Location
Williamsburg Virginia
........So, taking into account that drag on a vertically-falling Frisbee is likely insignificant, .......

I would not assume this given the highly asymmetric shape. The frisbee would probably flutter down to the ground once it lost rotational velocity .......

However, your calculations are probably correct for what hypothetically we may have done. Specifically, let eggs sit outside for three weeks (it was very hot before the ND game as I recall). An egg thrown from the upper deck would do real damage, especially if it hit on the structurally strongest aspect of either end.

As @Yjacket82 said, we'd get put under the jail today, hypothetically of course. But then again, putting a several week old dead shark in an opposing frat swimming pool wouldn't be favorably received either. Or taking a 10 oz bottle rocket and putting a dart tip in it so it would go through windows (the resulting couch on fire could hypothetically excite people).

Like I have said, I don't jump the players too much for doing stupid things; others have done stupider (sic) things before them.
 

bartoma

Jolly Good Fellow
Messages
357
Location
Herndon, VA
I would not assume this given the highly asymmetric shape. The frisbee would probably flutter down to the ground once it lost rotational velocity .......

However, your calculations are probably correct for what hypothetically we may have done. Specifically, let eggs sit outside for three weeks (it was very hot before the ND game as I recall). An egg thrown from the upper deck would do real damage, especially if it hit on the structurally strongest aspect of either end.

As @Yjacket82 said, we'd get put under the jail today, hypothetically of course. But then again, putting a several week old dead shark in an opposing frat swimming pool wouldn't be favorably received either. Or taking a 10 oz bottle rocket and putting a dart tip in it so it would go through windows (the resulting couch on fire could hypothetically excite people).

Like I have said, I don't jump the players too much for doing stupid things; others have done stupider (sic) things before them.

I dunno... Just based on my recollections (and subsequent anecdotal experience), I would bet on a Frisbee coming down at a high rate of speed, on edge, in a near vertical dive as opposed to "fluttering"...

I should ask my Dad (AE '56) - he spent a career at Lockheed/Marietta in aerodynamics and operations research... Besides that, he built and flew a Sonerai 2... :)
 

AE 87

Helluva Engineer
Messages
13,016
Without thinking about it too deeply, my gut says that a frisbee isn't ever going to fall like a rock. Without rotation, I think the lip would keep it from staying vertical (perpendicular to ground), and once horizontal (parallel to ground) the increased drag would probably cause it to flutter. In fact, I think it would be pretty hard to throw it in a way to keep it vertical because you're going to have the contributions of torque and the aerodynamic lift from the frisbee's shape. Again, didn't think about it too much, just my two cents.
 

bartoma

Jolly Good Fellow
Messages
357
Location
Herndon, VA
Without thinking about it too deeply, my gut says that a frisbee isn't ever going to fall like a rock. Without rotation, I think the lip would keep it from staying vertical (perpendicular to ground), and once horizontal (parallel to ground) the increased drag would probably cause it to flutter. In fact, I think it would be pretty hard to throw it in a way to keep it vertical because you're going to have the contributions of torque and the aerodynamic lift from the frisbee's shape. Again, didn't think about it too much, just my two cents.

Methinks an experiment is in order... :-D
 

Blumpkin Souffle

Bidly Biddington III
Messages
1,367
Umm, yea - prior to the BEE from GT and MSEE from VT - Bro... I also English... and write...

Do you do aerodynamics? A Frisbee, launched horizontally from 100-200 feet AGL (or whatever), will continue to travel horizontally some distance - and as you say, it will, at some point, no longer remain upright... But after this happens, it will fall on its edge in a near-vertical path towards the fore-mentioned band member's skull... And that's not even taking into account the likelihood that the student launching said Frisbee is throwing it deliberately at an upward and tilted angle to accentuate its subsequent dive to the ground...

So, taking into account that drag on a vertically-falling Frisbee is likely insignificant, and assuming it's falling from, say, 150 feet, it gonna be traveling at something on the order of 60 mph... And is this Frisbee weighs something like 90 grams (roughly 3 ounces), this results in an impact of approximately 40 joules - well within the range (14-60 joules) that can cause a fracture to the human skull...

Sources:

http://www.angio.net/personal/climb/speed

http://www.omicsonline.com/open-access/2090-2697/2090-2697-2-108.pdf?aid=15101
Why yes actually I do English and write. Even if you hadn't posted about being a student in the 80's one could guess that you are old enough to be a parent to many of the posters on this board by your response. "Bro, do you even physics" is a modern take on the classical meme "Bro, do you even lift?"

“Do You Even Lift?” (DYEL) is a condescending expression used on body building and fitness forums to question the legitimacy of someone’s fitness expertise or weight lifting routine. Similar to other interrogatives like “U Mad?” or“U Jelly?”, the phrase is mainly used to aggravate another user during arguments about physical fitness.
Source 1

Now with regard to the physics problem, I applaud your effort, but as @GTNavyNuke said you can't just ignore drag. My previous post stated that the drag would counteract the angular momentum to the point where it would become unstable and flare out. A solid object thrown from that high I'm sure would cause severe head trauma, but just don't see a frisbee doing that. Then again I'm not an AE and don't fully understand the flight dynamics of a frisbee so if someone could give a better model that would be great.

Of course I'm assuming you were throwing it correctly and not like these guys
 

ClydeBrick

Ramblin' Wreck
Messages
944
This website has to be the geekist football website on the planet.

And I love it. :D



Oddly enough, one of the videos that is linked to the Bosnians flinging their Frisbee is a one where "The Greatest Game of Horse" (Frisbees vs basketballs & footballs) is recorded and at the end the guy throws a Frisbee into a basketball hoop from the Vulcan tower in Birmingham. Unfortunately it does not discuss the force of the impact.
 

LibertyTurns

Banned
Messages
6,216
Kind of an off-topic derail, but what about the grilling Lefty Drissel (sp???) took at the GT-Maryland game in the 80's.
The empty gas tank skullcaps for Lefty were pretty cool
Yo' Adrian, wanna toke? on the 6' long joint replica after Adrian Branch got caught with the goods
The day Domino's ran out of pizza boxes when we greeted Lorenzo Charles after he stole the pizza
Can't remember who we threw the panties at. One dude got kicked out for holding up a playboy centerfold poster when he stepped up to the freethrow line. If I recall it was a MD player but something tells me it may have been one of the Dook fairies. It's even possible it was multiple games/teams. $2 flasks were common back then.
There was a ***** the PUSSYcats banner a frat ran across the field at a Clemson game.

Man those were the days. The cops could run up on you while frolicking with the ladies in the fountain & they'd give you a warning. Loud music, too much beer, pyrotechnics, repositioning of campus property & out of control pranks. Maybe you'd get an earful from Dean Dull & put on double secret probation or made to perform some unsavory work for someone in need. We seemed to turn out alright despite the uncivilized behavior. I feel sorry for today's kids. We had it good. Now you get the eject button, jail, etc.

By the way, having been in the presence of someone that nailed a tuba player from the upper deck I can vouch for the fact it puts a sizable dent in the tuba bell(?) when taking a direct hit. My recollection is 60mph would be an accurate guestimate. You definitely do not want to take a direct shot from anythng launched from the upper deck.
 

AE 87

Helluva Engineer
Messages
13,016
Why yes actually I do English and write. Even if you hadn't posted about being a student in the 80's one could guess that you are old enough to be a parent to many of the posters on this board by your response. "Bro, do you even physics" is a modern take on the classical meme "Bro, do you even lift?"

“Do You Even Lift?” (DYEL) is a condescending expression used on body building and fitness forums to question the legitimacy of someone’s fitness expertise or weight lifting routine. Similar to other interrogatives like “U Mad?” or“U Jelly?”, the phrase is mainly used to aggravate another user during arguments about physical fitness.
Source 1

Now with regard to the physics problem, I applaud your effort, but as @GTNavyNuke said you can't just ignore drag. My previous post stated that the drag would counteract the angular momentum to the point where it would become unstable and flare out. A solid object thrown from that high I'm sure would cause severe head trauma, but just don't see a frisbee doing that. Then again I'm not an AE and don't fully understand the flight dynamics of a frisbee so if someone could give a better model that would be great.

Of course I'm assuming you were throwing it correctly and not like these guys


Am I the only one who didn't notice how they were throwing the frisbee first time thru?
 

bartoma

Jolly Good Fellow
Messages
357
Location
Herndon, VA
Why yes actually I do English and write. Even if you hadn't posted about being a student in the 80's one could guess that you are old enough to be a parent to many of the posters on this board by your response. "Bro, do you even physics" is a modern take on the classical meme "Bro, do you even lift?"

“Do You Even Lift?” (DYEL) is a condescending expression used on body building and fitness forums to question the legitimacy of someone’s fitness expertise or weight lifting routine. Similar to other interrogatives like “U Mad?” or“U Jelly?”, the phrase is mainly used to aggravate another user during arguments about physical fitness.
Source 1

Now with regard to the physics problem, I applaud your effort, but as @GTNavyNuke said you can't just ignore drag. My previous post stated that the drag would counteract the angular momentum to the point where it would become unstable and flare out. A solid object thrown from that high I'm sure would cause severe head trauma, but just don't see a frisbee doing that. Then again I'm not an AE and don't fully understand the flight dynamics of a frisbee so if someone could give a better model that would be great.

Of course I'm assuming you were throwing it correctly and not like these guys


Ah, well, yes - we all do have our idioms peculiar to our own generation... Yours is noted... :)

I still don't think Frisbees "flutter" - I think they usually spill off to one side and accelerate towards to ground... Of course, this is exacerbated if the initial launch in other than horizontal...

Take a look at this video - looks like it's got a serious downward component to its velocity when it hits the ground... Now imagine if he had launched it skyward, 45 degrees off axis - I bet that thing comes screaming down fast enough to put a good dent in someone's hat...

 

AE 87

Helluva Engineer
Messages
13,016
Ah, well, yes - we all do have our idioms peculiar to our own generation... Yours is noted... :)

I still don't think Frisbees "flutter" - I think they usually spill off to one side and accelerate towards to ground... Of course, this is exacerbated if the initial launch in other than horizontal...

Take a look at this video - looks like it's got a serious downward component to its velocity when it hits the ground... Now imagine if he had launched it skyward, 45 degrees off axis - I bet that thing comes screaming down fast enough to put a good dent in someone's hat...



Ref to flutter was always if the angular momentum stopped without reference to how likely that would be. Clearly, in your video it's still spinning. However, it's hard to tell from that video what distances we are seeing from when it bounces off the sloping top/side of the building.

Here's a video that's a little closer to the scenario:



It could be that the kid broke his hand, but it didn't sound like it.
 

RLR

Jolly Good Fellow
Messages
355
The old folks and your stories :). Gotta love GT's history of pranks. I have to imagine we're top 5 among American unive...post-secondary education places. I guess when you take the smartest group of 18-22 year olds and give them whiskey, F's, and limited female company, you're providing all the ingredients for a good prank.

That said, I think the young alumni pranks have kept pace. Stealing the VT jerseys? I mean, smells don't show up on TV. Those scrub replacements jerseys do.

There's the classic kid sitting alone at a football game with his laptop doing homework picture. Which is great, because I loved having my parents/employers think that was representative of me.

Along those lines, when we got killed by LSU in the peach bowl, the 2nd half became a paper airplane contest. GT dominated, decent amount landed on the field.

I believe Matt Ryan and Boston College also published something in the technique about not liking being hit by alcohol bottles...which is definitely an effective response

There were the FBI raids in the freshmen dorms when paypal and i think one of the major credit cards got hit over the wikileaks payment thing...which again, I love being associated with a school whose freshman may or may not have taken down the largest payment firms in the world. I dread the day when my boss figures out "ya, i can do that, let me just play around with it = ya, let me google it, find the answer, and then tell you"

I remember lots of napalm incidents on campus. Some fierce firework battles. Lots of hitting golf balls off roofs. The football stadium and old basketball stadium's roof were popular hangouts. I also found a grenade one time on east campus. That was weird, but I was late to class so... I guess my point is, it all works out in the end. Why go all UGA, athens-clarke county over college.
 

Animal02

Banned
Messages
6,269
Location
Southeastern Michigan
The old folks and your stories :). Gotta love GT's history of pranks. I have to imagine we're top 5 among American unive...post-secondary education places. I guess when you take the smartest group of 18-22 year olds and give them whiskey, F's, and limited female company, you're providing all the ingredients for a good prank.

That said, I think the young alumni pranks have kept pace. Stealing the VT jerseys? I mean, smells don't show up on TV. Those scrub replacements jerseys do.

There's the classic kid sitting alone at a football game with his laptop doing homework picture. Which is great, because I loved having my parents/employers think that was representative of me.

Along those lines, when we got killed by LSU in the peach bowl, the 2nd half became a paper airplane contest. GT dominated, decent amount landed on the field.

I believe Matt Ryan and Boston College also published something in the technique about not liking being hit by alcohol bottles...which is definitely an effective response

There were the FBI raids in the freshmen dorms when paypal and i think one of the major credit cards got hit over the wikileaks payment thing...which again, I love being associated with a school whose freshman may or may not have taken down the largest payment firms in the world. I dread the day when my boss figures out "ya, i can do that, let me just play around with it = ya, let me google it, find the answer, and then tell you"

I remember lots of napalm incidents on campus. Some fierce firework battles. Lots of hitting golf balls off roofs. The football stadium and old basketball stadium's roof were popular hangouts. I also found a grenade one time on east campus. That was weird, but I was late to class so... I guess my point is, it all works out in the end. Why go all UGA, athens-clarke county over college.
. Adding to your list.....the first time they did a computer lottery for dorms....it was hacked...it was on discovered because no foreign students got dorms (the hack base the drawing on the 8 the digit of your SSN which was used as you I'd back then.....no foreign students had a SSN sf o they got sent to the bottom. Then there was the time shortly after computer registration took over and George P. Burdell managed to enroll in every section of every class offered that quarter.
 
Top