Bottle Rocket B

[chalker]

I don't see any restrictions on length of the rocket. Am I correct on that? Also you smell nice.

Yes I'm pretty sure. But your bottle can only be a max of 2 liters.

There is no limit on the length of attachments to the 2 liter bottle. General rule #1 applies: http://soinc.org/ethics_rules

[chalker]

If you look at the spec sheet there are rules and my team member and I have tested it 3 times each with/without the ping pong ball.

Even only 3 times might not be enough to establish a significant difference (20% in your case). There are so many parameters to consider: wind speed / direction, air temperature / pressure, water level, etc.

[RaisinBrandon]

I don't see any restrictions on length of the rocket. Am I correct on that? Also you smell nice.

Yes I'm pretty sure. But your bottle can only be a max of 2 liters.

There is no limit on the length of attachments to the 2 liter bottle. General rule #1 applies: http://soinc.org/ethics_rules

I said the bottle can be only a max of 2 liters, not the attachments

[scio_musca]

Hi,
Wanted to find out what flight times other schools are getting. We are currently getting a flight time of 10 seconds. Is this good enough to do well at regionals and state?

[Unome]

Hi,
Wanted to find out what flight times other schools are getting. We are currently getting a flight time of 10 seconds. Is this good enough to do well at regionals and state?

Being in California, I'm not really sure. That might get you a medal at Regionals (depending on how big your Regionals is)

[RaisinBrandon]

Hi,
Wanted to find out what flight times other schools are getting. We are currently getting a flight time of 10 seconds. Is this good enough to do well at regionals and state?

I got a constant 11 sec... Until it crashed in the teachers lounge.

[sciolympiad]

Hello, I know that parachutes are not allowed in Bottle Rocket but are wings?

[Toms_42]

Hi,
Wanted to find out what flight times other schools are getting. We are currently getting a flight time of 10 seconds. Is this good enough to do well at regionals and state?

10 seconds should be fine for regionals, although something like 15-20 is a good target for states/nationals.

[Unome]

Hi,
Wanted to find out what flight times other schools are getting. We are currently getting a flight time of 10 seconds. Is this good enough to do well at regionals and state?

10 seconds should be fine for regionals, although something like 15-20 is a good target for states/nationals.

Looks like we're still as good as we were before, then.

[joeyjoejoe]

Hi,
Wanted to find out what flight times other schools are getting. We are currently getting a flight time of 10 seconds. Is this good enough to do well at regionals and state?

I'm in division C so I haven't read the rules but at 10 seconds, I'll bet you have a "lawn dart". There are plenty of things you can do to fix this but, since I don't have a copy of the rules, I'd have let you determine if they are allowed.
1. Can you drop the nosecone weight at apogee? Probably not but this adds a great amount to your time if allowed.
2. How long can the rocket be? With a longer rocket, you have more leeway to adjust important parameters such as CLA (center of lateral area), CG (center of gravity) and the always hard to determine: CP (center of pressure).
Going up, if the CG is at least one diameter (average width of the rocket) ahead of the CP, it will fly straight. Coming down, the physics is different. If the CP (the point that we can consider the atmosphere pushing on the rocket), roughly coincides with the CG, it should fall flat instead of nose down.
In a nutshell, if you can design a rocket with a CLA just ahead (toward nose an inch or so) of the CG and provide a perfect combination of nosecone weight (moves the CG toward nose) AND fin size (moves CP backwards, away from nose) you can create a "back slider". I have one that I built that can reach 150m at 60 psi and has stayed aloft for 27 seconds.
Again, I have no idea what the rules state but you might want to Google "back slider water rocket". There is plenty of info out there on this. One of the most famous is the "Coney" which has a ridiculously long nose cone.

It is really neat watching these backsliders reach full height and then literally pausing at apogee followed by a short backward (yes backward!) slide downward until, within meters, they become horizontal with the earth and fall slowly and gently down with the fins spinning like a pinwheel. You don't have to worry about a backslider destroying itself on landing. In fact, if you were to get hit by one of these, it wouldn't hurt at all. Meanwhile, one of my lawn-dart rockets put a large dent in the roof of my truck!