Heat and sight marks

[sambow]

Hi Wendy It would be great if you could do this and you raise some interesting considerations.

You are right to try and simulate as much "true life" conditions as possible. I am guessing that the bow is likely to spend much of its time in the sun, certainly most people at our club hold the bow to shoot (in the sun) and then put it to rest while they collect (in the sun). but you have more competition experience than me and I don't know how many people use pop a bivvys in competitions and these may keep the bow cooler. One consdieration though would be the solar effects on the hooter shooter. Its a long time since I've seen pictures but from memory it is a heafty metal construction. This could get hot in the sun and I beleive this may influence the outcome. If at all possible I would recommend shading the hooter shooter but leaving the bow on a stand in the sun and fitting it before each round shot (but i don't know how impractical that is!).

Regarding the arrows I guess most of the time they are either in a quiver, warming up, then flying throught the air (which I would guess cools them down) then on a boss heating up in the sun and then back in the quiver. So I would guess they are not going to be subjected to the effects of heat like a bow will as they get a chance to cool. so it may be worth while storing them in shade between shots.

I really hope you can find time to do this and look forward to the outcome.

[worthipa]

Originally Posted by not dead yet

what does the hooter shooter do exactly. please

Oh come now ....!

What does a Hooter Shooter do exactly?

[ben_e71]

JUne the 21st is the longest day and is a Saturday - it would allow you daylight from about 4am to 10 pm

[archery_mum]

Yes I think the Hooter Shooter would need to be shaded and this in itself isn't a problem.

June 21st - I will have to check my diary, and of course the weather forecast would need to be reasonable.

[bimble]

The general question is whether it is the temp causing the arrows to change, or the change in air pressure.

ie - does the change in temp of bow cause an increase/decrease in stored energy or,
does the change in air pressure cause an increase/decrease in arrow drag.

So you would need; a thermometer by the bow to measure local temp changes, a day on which there was a steady high pressure in the area (so it's not expected to change too much) and a barometer to check the air pressure in case there is any change during the day.

You would then have to record (every hour or so) the height of the arrows in the target, the temp and the air pressure.

[Watch_Man]

Originally Posted by bimble

The general question is whether it is the temp causing the arrows to change, or the change in air pressure.

ie - does the change in temp of bow cause an increase/decrease in stored energy or,
does the change in air pressure cause an increase/decrease in arrow drag.

So you would need; a thermometer by the bow to measure local temp changes, a day on which there was a steady high pressure in the area (so it's not expected to change too much) and a barometer to check the air pressure in case there is any change during the day.

You would then have to record (every hour or so) the height of the arrows in the target, the temp and the air pressure.

In my gadget box I have enough machines that go bing to start my own National weather service, so we should be OK

[BorderBows]

the carbon is meant to be fairly temperature stable, so the next thing would be the core. Our core is primarly temp stable. That is its industrial application, it breaks up if outside its temp range of its stability which is not available in any human shooting environment. We use it as its a great core material. Its also NOT a foam. We dont use foam, so we dont claim to know what a foam is like in the practicality of every day shooting


The next point is "human performance drops in heat", which is the one we think is most likely.
Top atheletes (as in runners) have been known to use ice baths to cool down before a race?

[Flying Whale]

Originally Posted by BorderBows

The next point is "human performance drops in heat", which is the one we think is most likely.
Top atheletes (as in runners) have been known to use ice baths to cool down before a race?

This is the whole point of this experiment. As suggested earlier in the thread. Using the hooter shooter removes the "athletes performance in the heat" from the equation.

As far as I see it at this point it would not distinguish differences in arrow flight amongst

a. air pressure changes affecting arrow flight
b. temperature changes affecting bow/arrow material performance.

It is not intended to knock anybody, or anything. Just to try and remove a variable from the mish-mash of guesswork.

[bimble]

It would depend on what results are achieved.

If, for example there is a change of air pressure during the day, but not of air temp, then whether the arrows moved could be pointed at the change in air pressure.

One of the reasons why I suggested that a day when there was a large high pressure over the country was the fact that the air pressure would not be chanigng much but the temp would.

In reality I suspect that there would be an effect from both air pressure and temperature, but that of the air pressure will be so negligible that it can be ignored.

Makes me wish I could go play in the wind tunnel now...

Originally Posted by Flying Whale

As far as I see it at this point it would not distinguish differences in arrow flight amongst

a. air pressure changes affecting arrow flight
b. temperature changes affecting bow/arrow material performance.

[Flying Whale]

Originally Posted by bimble

It would depend on what results are achieved.

If, for example there is a change of air pressure during the day, but not of air temp, then whether the arrows moved could be pointed at the change in air pressure.

One of the reasons why I suggested that a day when there was a large high pressure over the country was the fact that the air pressure would not be chanigng much but the temp would.

In reality I suspect that there would be an effect from both air pressure and temperature, but that of the air pressure will be so negligible that it can be ignored.

Makes me wish I could go play in the wind tunnel now...

I should probably have said "would not necessarily distinguish...". By being more rigorous in trying to control other factors (as you suggest) it is more likely to be able to say something meaningfully positive. I think however, the first step of being able to positively rule a factor out (i.e. the archer) would be a good thing to do.

After that having someone prepared to allow their bow to be frozen and baked would be great....any takers?