To use these data, it seems like we need to take the ambient wind data measured on a "representative" course (people can debate which course it should be, but based on the data in the article there seems to be a low sensitivity....so go with Kona since everyone puts that on a pedestal).

With that wind data, you could take the known drag of different bikes/wheels at yaw, plug in a given rider wattage, and do a simulation run to see what the time savings is. The output will be different for a "pro" (300W) vs. a "solid AG" (200W) vs. a "bucket-lister" (150W). If you know your watts (or can backwork from you bike splits) you can see what setup works best.

The time at each yaw angle on the graphs is a bit deceptive since climbing at low speeds leads to higher yaws, but on a part of the course where aero gains are minimal.

fishboy wrote:

You definitely need the yaw distribution and your drag at that yaw to better estimate your total time.
This info from Nathan also makes it a lot more important that you get pacelining correct... if large amounts of time are less than 10 deg yaw, you can easily get a large slipstream benefit even at draft legal distance of 12 m.

Yep.


Adding from left to right: 1% + 19% (skip -10 to +10) + 5% + 5% = 30% of time at Kona spent outside 10 degrees yaw. (Where on the course does this happen? What are the conditions there? What about the other 70% of the time?)

Another poster also mentioned, a specific course may have a unique yaw distribution. As another example, there's a club in St. John's, Nova Scotia, whose weekly TT has consistently high winds, leading to consistently high yaw angles. It's out & back, so you get high positive and high negative yaw.

So if your A race has a predictable yaw distribution, you can select equipment that does well at those yaw angles.

On the other hand, if you race "everywhere," or if your A race has normally variable wind conditions, then your most commonly experienced yaw angles center towards the range in the article.

No comment on any of this stuff, except.... Where is St John's Nova Scotia?

My ignorance is revealed. :-( I meant St. John's Halifax.



Surrounded by the sea, you can imagine the winds there... I mean, you probably don't have to imagine them, but "one can imagine" the winds there.

Yup: A 10% - 13% reduction in apparent CdA when drafting at 12 metres in this (your) case:
http://alex-cycle.blogspot.com.au/...2/pour-me-draft.html