Well, if the wealth of comments after my last blog is anything to go by, the darting world in general (and Red in particular!) is currently in a notably inquisitive frame of mind regarding the wonders of flight dynamics. So, as it would be remiss of me to dampen such laudable scientific interest in pointy flying things, I must give over the majority of this latest little epistle of mine to an extensive Q&A section.
But before I do, here’s a quick answer to a question that, in one form or another, keeps rearing its ugly head; how important is aerodynamic drag to dart designers?
And the quick answer is…… forget drag, it’s lift they should be worrying about!
In due course I may justify this statement in more detail, but for now I’ll just point out that all the forebody, skin friction and base drag created by the barrel, shaft and flights will only slow down a typical dart thrown at 6 m/s by less than 0.02 m/s and increase its flight time by under a millisecond. The resultant extra “gravity drop” will be under 2mm and, as even this small effect would be pretty repeatable, the risk of a dart being simply “dragged” down far enough to miss its target bed are negligible.
By comparison, as discussed in my past blogs like “The Good, the Bad, and the Ungainly”, lift acting on the flights can throw a dart off-course by a lot more than 2mm. As the yaw which causes the lift can also vary a fair amount, we can thus safely conclude that lift is far more important to dart accuracy than straightforward drag.
However, I must confess to a teensy complication to this nicely simplifying conclusion, something called “lift-induced drag” - of which more another time……
Q&As
Carey Bock and Phil Taylor Phase 5s
Yes, Carey, Phil does indeed use the Phase 5s, which have evolved from a combination of the John Lowe Hero 26gm barrel and Sigma Pro shafts.
Dave Burgess and Barrel Dimensions
Herewith, in mm, the maximum diameter/length of the Sigma and Gripper Barrels:
Sigma 970: Steel Tip: 21gm/7.06/43.45: 23gm/7.56/42.06: 25gm 8.01/41.46: 27gm/8.49/40.55: Soft Tip: 19gm/6.69/40.00
Sigma 950: Steel Tip: 18gm/6.41/45.79: 20gm/6.78/44.96: 22gm/7.36/43.07: 24gm7.76/42.60: 26gm/8.33/42.06: Soft Tip: 18gm/6.76/41.00
Gripper Type 1: Steel Tip: 21gm/6.35/50.55: 23gm/6.58/50.55: 25gm/6.83/50.55: Soft Tip: 17gm/6.35/42.93: 19gm/6.35/47.63
Gripper Type 2: Steel Tip: 20gm/7.93/38.10: 22gm/7.93/41.66: 24gm/7.93/44.75: Soft Tip: 18gm/7.62/37.59: 20gm/7.75/40.13
Hope that little lot helps you find the right one for you, Dave!
Bob and Red on Aerodynamic Drag
This is a complex topic and one I shall no doubt return to in the future, especially with regard to yawed flights. In the meantime, I hope this blog will help to explain why, as Red picked up on in one of his comments, most aspects of the aerodynamic drag of darts are of academic rather than practical interest!
Warren and Square Noses
Welcome back, Warren, and best wishes for your return to good health. The square nose issue you raise was briefly covered in my last “Sigma Squared” blog as a less-then-desirable manufacturing necessity that we’ve tried to mitigate on the new Sigma 950s by using a slightly lower percentage, more malleable, tungsten alloy. I hope players find that the increased nose taper on these darts will help reduce flight damage.
Bob and Sigma 950s
I believe some Sigma 950s will soon be on their way to US suppliers, Bob, but if you have no luck locally you could try getting them by mail order from a UK company such as Mad On Darts (www.madondarts.co.uk), who should have them shortly.
Red and Heritage Darts, uniLab, etc
Although the old Modus dart from 1986 was not designed by me, Red, it is true that, as I admitted in one of the Q&As to the “The Good, the Bad, and the Ungainly” blog mentioned above, I am senile enough to have been working with Unicorn on dart design as far back as then. However, as I explained in that Q&A, my work only really came to concrete fruition recently with the launch of Sigmas and uniLab.
Red also asked how much further technology can take us down the uniLab road of a player selecting the dart best suited to their style rather than adapting their style to suit a dart they have chosen on some other basis (such as their favourite pro using it). The answer to this is, in theory, quite a way. Although uniLab can give good generalised results, more player-specific recommendations could be made by an expert using tools such as slow-motion video analysis and detailed dynamic computer models. Indeed, two Unicorn players (you’ll have to guess who!) have already been through this process. However, it might be quite a while before a similar facility is available to the general public! Moreover, the over-riding importance of the psychological element in darts and its potential influence on equipment choice must never be underestimated.
As a final point, Red, because uniLab can only give generalised recommendations, although the scores it provides are measures of accuracy and trueness of flight, they not meant to be taken too literally and are calibrated just to be a convenient metric for ordering the results. Incidentally, it should be noted that the score is dependent on player standard, so 100% could only be achieved by a completely error-free dart thrown by a player who never misses. For example, the best real dart for a pro might score 97% whereas the best one for a novice might only get 85%.