WSC 2023: end of Day 3

Hey folks - I'm chilling out at the Marla Traveller's Rest tonight at the conclusion of the third day of WSC 2023, and what a race it's been. For an at-a-glance race summary of the Cruiser Class, check out this chart from Tony at Scientific Gems:

Chart via Scientific Gems
"Two speeds are shown for each team:
the first is the average speed since Darwin;
the second (in brackets) is the average for the last leg."

Other good links: WSC's Tracker Map and a .kml file for Google Earth, a WSC Challenger Graph similar to Tony's (but inverted), and a WSC Cruiser Graph as well.

The first day this year was a great day for solar racing. The second day saw increasing amounts of smoke along the course dimming the skies (a few team members told me they spend the second night sleeping in N95s), and a front rolled north over our position on the second night bringing in headwinds, cooler weather, and patchy clouds for the third day that I am told will persist tomorrow.

I have largely been following along with the teams up at the very front, and the big three up there have been Innoptus (Leuven), Twente, and Brunel (Delft). Innoptus took an early lead on the first day, and between Dunmarra and Tennant Creek they had achieved a >30 minute lead - they departed the Tennant Creek, Barrow Creek, Alice Springs, and Erldunda control stops before Brunel and Twente arrived. They also managed to arrive at Alice Springs just before the end of the second day; the checkpoint there was not scheduled to open until the following morning and the race officials had to scramble to be ready in time for Innoptus's arrival! And speaking of Innoptus, a few people online have been speculating about how much use they are getting out of that retractible fin or if it's mostly just being used for photo shoots. All I can say is that we have overtaken them somewhere between 6 and 8 times, and the fin was extended on all but one occasion...

Further back, Brunel was in second place soon after the start, but began slowing down on the second day of the event and was passed early on by Twente. As we've faced headwinds on the third day of the race, Twente has closed the distance to Innoptus and are almost back to the point they'll be meeting at control stops again - it's very much still anyone's race!

Behind Brunel, Michigan has steadily been catching up. During qualifying, Michigan encountered issues on their hot lap and were forced to start at the very back of the starting grid. I'm told they overtook something like 25 teams on the first day alone... they spend large parts of the first day grouped up with Kogakuin and Top Dutch, and ended the first day at Dunmarra with those two and Tokai. They turned on the gas on the second day and made up quite a bit of time, and although they slowed down in the clouds and headwinds on the third day just like everyone else, they didn't slow down as much as Brunel and have closed from an hour and forty minute gap at Tennant Creek to just under an hour at Erldunda. Barring any mistakes or breakdowns by Brunel, in the distance remaining it will be a challenge for Michigan to close the remaining distance to overtake for 3rd place, but they have a chance...

About half an hour behind Michigan are Tokai in 5th and Sonnenwagen Aachen in 6th.

Tokai has been running a very steady race, they've been comfortably in 5th place for essentially the entire even thus far - momentarily falling to 6th when overtaken by Michigan, but climbing back to 5th after overtaking Sonnenwagen.

Sonnenwagen got the pole position at the start and hung onto 3rd place closely with Innoptus and Brunel up through Katherine, but have slowly and steadily fallen back - by Tennant Creek they had been overtaken by Twente and were in 4th, they had clearly fallen out of the lead group by Alice Springs, they fell to 5th by Erldunda, and were passed by Tokai before the end of the third day. 

Behind Sonnenwagen is a 2+ hour gap back to Top Dutch in 7th, another hour and a half or so back to Kogakuin, and the remaining cars are spread out behind. The current running order from 9th onward appears to be JU, Durham, Eclipse, WSU, αCentauri, Blue Sky, Goko, Chalmers, Adelaide, Halmstead, and Wakayama; all other teams appear to have stuck the car on the trailer. Halmstead and Wakayama do not appear to be on a pace to finish the race; we'll see if Chalmers and Adelaide can hang on. There may be some excitement in the back: WSU, αCentauri, Blue Sky, and Goko have been running extremely tightly together for the entire event and 12th appears to be the most tightly contested place in the Challenger class.

On the Cruiser side, right now it's Sunswift's competition to lose. Cruiser teams were supposed to arrive at Tennant Creek at 2:00pm on the second day, and if late they would start accruing a 0.99^(minutes_late) penalty multiplied against their score. Sunswift was the only team that arrived on time, Minnesota was next at 52 minutes late (penalty multiplier of 0.59), Apollo was 63 minutes late (multiplier of 0.53), Solaride was 65 minutes late (multiplier of 0.52), Ascend was 94 minutes late (multiplier of 0.39), SunShuttle was 128 minutes late (multiplier of 0.28), and the remainder appear to be out of the event. 

Via https://telemetry.worldsolarchallenge.org/contrib/vision/cruiser.html

It's especially heartbreaking for Minnesota, who were on a pace to finish before the target time... until they had some sort of issue and parked their car almost a full hour before the end of the first day, putting them off the back of the pack of Cruiser cars. They were the fastest Cruiser car on the second day, but it wasn't enough to make up for the time they'd lost.

It remains to be seen what the external energy usage and person-km for each team are, and of course practicality is a big black box at the finish line, but Sunswift has been carrying four people in the car for almost the entire even and I expect them to do very well on practicality, so it's hard to see how any other team can come back from those penalty multipliers. Of course Sunswift could also have some sort of issue and accrue a large penalty multiplier, but looking ahead to the second stage, Sunswift is the front-running Cruiser team at the end of the first day of the stage and appears to be on pace to hit Coober Pedy by the required 4:30pm time. Minnesota also remains on pace, while Solaride and Ascend slowly slip back, and Apollo apparently has suffered some sort of critical problem and will certainly miss the 5:00pm hard cutoff, leaving only four cruisers left in the running.

Ok - gotta hit the tent and get some sleep for the drive ahead tomorrow. I'll leave you with some photos:

A very confused road train driver trying to enter the Katherine weighstation

Sunset at Dunmarra

Fire and smoke between Barrow Creek and Ti Tree on the second day
We could feel the thermal radiation passing this fire from inside our car
Innoptus was ahead of us at this point, Twente and Brunel behind