'Make a sail' or 'go aero' uphill with a stonking tailwind?

[mjr]

Yes, but depressingly rare ... The valley system round here seems to funnel the winds in a strange way. It is often possible to do a circular ride and get cross/headwinds 75+% of the time!

Oh everywhere has quirks like that. If you live on the coast or near a major estuary, tidal winds can give you headwinds 75+% of the time... but I did one 100 mile ride last year where we had tailwind or cross-tail wind for 81 miles, which I think was partly due to that effect. The 19 miles into a battering headwind still felt like 1900, though!

Back to the question: I'd sit up every time - not quite "make a sail" if it's uphill, but I've freewheeled over 20mph on the flat thanks to a tailwind before. Mind you, we only managed 6mph into that wind, so the average still stank.

 

[Oldfentiger]

Yer all overthinking it!
Have you got a NET tailwind or headwind.
Examples......
If you're pedalling at 10mph with a 15mph tailwind then you have a net tailwind of 5mph, so sit up and reap a miniscule benefit.
If you're pedalling at 10mph with a 5mph tailwind then you have a net headwind of 5mph, so get down and reduce your frontal area (unless you can raise a 5mph fart).

 

[derrick]

I would say sit up. We have a couple of strava segments we do regularly, With a good tail wind you can save a bit of time, Depending how strong that wind is.

 

[2IT]

Isn't it ironic and unfortunate that our backside is more aero than the front side?

So while we would like to catch a lot of tailwind, we usually just pass it.

 

[ufkacbln]

Mike Burrows explained it something like this very simplified version:

Stand up and put your arms out - any wind direction forward of your arms will have a head wind component, and affect your forward motion