Elastic Launched Glider C

[erikb]

Such a prediction bonus would have the effect of penalizing teams with superior gliders and rewarding teams with average gliders, i.e. gliders not capable of flights with a 1 foot per second descent rate or better.

There is a lot i don't know about gliders, that's why i ask people who do, about a most things. However, I know this statement does not reflect reality in anyway.

The one thing i do know, is what kids with drop rates of 1.2+ can do with their gliders and in no way would a their gliders be at a disadvantage.

Next, I find it far less likely that a team would get a lucky win in such a controlled test. All teams could practice the exact same range of times, over and over, just like in GV. And like GV all teams would have the same opportunity to adjust for the environment. However, unlike GV the variables could be predetermined though math and physics since the science of air density in known. Compared to GV where surface conditions are are complete mystery box.

Next, if the heating and cooling is left on during the event it does boil down to who is the luckiest team no matter what criteria is set. There is no way a team can have just the right glider trimmed and ready to go, for when the air is full blast, barely moving or somewhere in between. Every flight will be different with no consistency no matter what the team does. So this argument that the bonus would be somehow different makes no sense.

Finally, even at a ceiling of 20' a good teams score would be 80 points with a bonus of 10. A really strong team would be in the 96 point range without bonus. So it's not a game changing bonus. It's a reward for hard work that moves a team up or down the ladder to reflect their actual skill not the luck of draw on balsa wood.

[retired1]

Proposed bonus for gliders

If this bonus is accepted then I will try and talk someone into publishing a paper that will describe all the math needed to predict times taking into account the differences in air density. It appears that it is something that with the right guidance a team can do.

As a retired USAF pilot, I would be very interested in having a copy of that paper.

[erikb]

Proposed bonus for gliders

If this bonus is accepted then I will try and talk someone into publishing a paper that will describe all the math needed to predict times taking into account the differences in air density. It appears that it is something that with the right guidance a team can do.

As a retired USAF pilot, I would be very interested in having a copy of that paper.

If i can talk someone into writing it, then it will be published for everyone to see.

A direct quote from one the people i asked about this:
"if I were writing the rules I would publish the formulas to be used by all teams for their analysis that is within their knowledge level. 'Use these formulas for your predictions and demonstrate by test data.' Then compare at the finals by demonstration."

Since, this is above what i understand about gliders, (or physics or in general) i went to people who know a lot more about it, then i do. I wanted to make sure it was a fair and reasonable bonus before i put it out there as an option.

Yes, it is all dependent on still air. Just like the scoring is. No matter what anyone does, if the air is not still, then each flight is random, without exception. Yes, heavier gliders will get a slight advantage but they still have to go through random points of air density and movement greatly effecting lift and making each run completely independent of the others. There would be no way to adjust for that. There would be no way of knowing in advance what the best trimming would be for random air.

[wlsguy]

The bonus you are describing, while possible, seems overly complex. I hate to make the event supervisors think too much.

The current method of adding flight times is easy to understand, rewards the teams who practice, and can be scored with a calculator.
My proposal to reduce the effects of luck and increase use of data is to score 3 of the 5 flights (assuming 2 of the flights may have issues due to room factors, air currents, etc). This requires the students to be more than 50% consistant and doesn't cause the people running the event to be concerned if the flight is "regular" or "bonus".

[erikb]

The bonus you are describing, while possible, seems overly complex. I hate to make the event supervisors think too much.

The current method of adding flight times is easy to understand, rewards the teams who practice, and can be scored with a calculator.
My proposal to reduce the effects of luck and increase use of data is to score 3 of the 5 flights (assuming 2 of the flights may have issues due to room factors, air currents, etc). This requires the students to be more than 50% consistant and doesn't cause the people running the event to be concerned if the flight is "regular" or "bonus".

Keep in mind i am not demanding the bonus be added. Just working out in my own mind and in a public forum, how to make flight logs relevant and not something made up 5 minutes before the contest.

So i am just answering the question: what is a fair and accurate way to measure the data collected on the flight logs? Nothing more then trying to find the best solution for the problem at hand.

However, I do agree that more than 2 flights should be scored.

[wlsguy]

The bonus you are describing, while possible, seems overly complex. I hate to make the event supervisors think too much.

The current method of adding flight times is easy to understand, rewards the teams who practice, and can be scored with a calculator.
My proposal to reduce the effects of luck and increase use of data is to score 3 of the 5 flights (assuming 2 of the flights may have issues due to room factors, air currents, etc). This requires the students to be more than 50% consistant and doesn't cause the people running the event to be concerned if the flight is "regular" or "bonus".

Keep in mind i am not demanding the bonus be added. Just working out in my own mind and in a public forum, how to make flight logs relevant and not something made up 5 minutes before the contest.

So i am just answering the question: what is a fair and accurate way to measure the data collected on the flight logs? Nothing more then trying to find the best solution for the problem at hand.

However, I do agree that more than 2 flights should be scored.

No problem. I like talking about everything because it ultimately will make everything much more clear when the rules are finalized.
After looking at flight logs from more than 200 participants this season, I can tell the teams who use it as intended and those who don't.
The teams who don't will never have a good repeatable glider and will succeed only because they can get lucky (40% of the time with the current rules).

[retired1]

Whatever the rules end up being, I think that they should be simple enough to be run at regional and state events without being a source of challenges. The Florida state contest has had at least one event thrown out due to challenges for the last 3 years.
If math is to be involved, then all of the formulas needed should be provided or readily available and apparent on the internet.

[erikb]

Whatever the rules end up being, I think that they should be simple enough to be run at regional and state events without being a source of challenges. The Florida state contest has had at least one event thrown out due to challenges for the last 3 years.
If math is to be involved, then all of the formulas needed should be provided or readily available and apparent on the internet.

This year every single build event had an excel spreadsheet. All anyone had to do was punch in the numbers.

Plus the formulas are in the book. It can all be double checked.

[retired1]

Whatever the rules end up being, I think that they should be simple enough to be run at regional and state events without being a source of challenges. The Florida state contest has had at least one event thrown out due to challenges for the last 3 years.
If math is to be involved, then all of the formulas needed should be provided or readily available and apparent on the internet.

The math I was referring to was if math calculations become a requirement for determining flight times for the bonus.

[jander14indoor]

That's the job of the students to figure out for their glider(s). If they know flight time vs height vs launch parameters for their glider they can adjust launch parameters to hit (in a statistical sense) any target time within the capability allowed by the ceiling. No calculations needed on the event supervisors part. The check of the students formulas comes from how close they hit that unknown target, not any inspection of the formulas themselves.

This is no different than the trebuchet based events where the students have a target distance (unknown before hand) to hit. They have to know the parameters to adjust on there device to launch that distance. No formulas are distributed to support them, though they exist on the web outside SO.

Jeff Anderson
Livonia, MI