Archers Paradox

[maxwell9699]

Having watched a lot of slowmotion filming of arrow flight. How far does an arrow have to travel before it assumes level flight by that I mean stops bending? This presumably would be the same distance that would enable effective bow tuning. i assume there would be a difference between recurve and compound.

[sp220]

Compound bows do not suffer from the paradox in the horizontal plane, this is because a release aid is used.

I have heard all sorts of wives tails about "when" an arrow finishes "wobbling", usually being around 20 yards or slightly less.

I would not be able to say what an accurate or exact distance would be for the arrow to fully level out... I would imagine the most accurate way to tell would be high speed camera...

But as a rule of thumb, somewhere between 10 - 20 yards couldnt be too far wrong.

[geoffretired]

I have watched slo mo vids of arrows being shot at 70m with recurves and they are still bending back and forth when they land.

[sp220]

Originally Posted by geoffretired

I have watched slo mo vids of arrows being shot at 70m with recurves and they are still bending back and forth when they land.

I remember seeing footage from the 2004 olympics only very slightly slowed to show arrow flight and the arrows did appear to still be moving arround alot.

I doubt the arrow every truly streightens out - but I think the most severe part is early, immediately after release..

[bimble]

Arrows do flex a bit with compound, only vertically (there was a slow-mo of Archery-mum on a thread in the last couple of days).

Just wondering Geoff if that's when they're landing, or jut before they are landing?? If it's as they are landing I would say that the bending there is due to the fact the arrow isn't hitting the boss straight and the rear of the arrow is trying to overtake the front of the arrow.

Originally Posted by geoffretired

I have watched slo mo vids of arrows being shot at 70m with recurves and they are still bending back and forth when they land.

It's honestly scary just how much arrows flex when they hit. Sometimes I'm surprised that they don't break everytime they're shot!!

[sp220]

Originally Posted by bimble

Arrows do flex a bit with compound, only vertically (there was a slow-mo of Archery-mum on a thread in the last couple of days).

Just wondering Geoff if that's when they're landing, or jut before they are landing?? If it's as they are landing I would say that the bending there is due to the fact the arrow isn't hitting the boss straight and the rear of the arrow is trying to overtake the front of the arrow.



It's honestly scary just how much arrows flex when they hit. Sometimes I'm surprised that they don't break everytime they're shot!!

If you look at footage from the 2004 olympics which has good view of the arrow flight, it is pretty much all the way to the target.

Although it does flex more when its hit the target, just look at the beiter vids...

[King Custard]

I think its safe to assume that an arrow will oscillate till it runs out of energy, is it not?

In which case it's still bending until it disperses that energy into the boss (or the ground)...at which point rapid deceleration will negate that original 'bend' and impart another...

as said though 20 yards should the 'bendiest' part of flight out of the way.

[Jerry Tee]

There will be no difference as long as the bow ( compound or recurve ) is shoot off fingers.

[Mad Archer]

Originally Posted by King Custard

I think its safe to assume that an arrow will oscillate till it runs out of energy, is it not?

In which case it's still bending until it disperses that energy into the boss (or the ground)...at which point rapid deceleration will negate that original 'bend' and impart another...

as said though 20 yards should the 'bendiest' part of flight out of the way.

This must go back to the principle of conservation of energy - energy is never lost, only transformed (I'm ignoring relativity at this point).

As you let go of the arrow, you give it both kinetic (forward motion) and vibrational energy. Leaving out the kinetic part, the vibrational energy remains until it is converted into another form. The only transformations I can think of are the transfer of energy to the air (air resistance) and the internal flexing of the shaft generating heat.

I can't see either of these mechanisms reducing the vibration of the arrow very quickly, so I'm not surprised that slow motion shows the arrow vibrating all the way to the target.

[maxwell9699]

Okay. From the replies so far the consensus appears to be that the arrow is dropping as it reaches the target, is drifting sideways if the wind is blowing but is also oscillating side to side. So that means the archer has to shoot so consistantly that the left right oscillation concides with the gold, and this oscillation is greater at the shorter distances.
Damn this archery is difficult.......anyone got a rifle?