Trailer Racing!

13 out of 37 cars have trailered (or will have to) by the end of day 2.

Once a car trailers the time is no longer relevant, and it's all about how many km they drive in the time available. This is where trailering time becomes important, and where the race becomes a trailer race. A good trailering strategy will help a tail runner team get as much solar car road time as possible. Charging while trailering will allow higher solar speeds and less trailering.

I believe a more structured official approach to trailering will help make trailering safer and fairer by removing incentives to trailer too fast or too long. Such an official trailering strategy would involved compulsory trailering stages and fixed start times for cars not reaching specific control points by given times. Such a strategy would help keep the field together, and get slow cars well forward so they can drive long stretches without constantly getting behind. It would effectively create a number for shorter sub-races for slower teams.

Officials could make exceptions for faster cars that have been delayed through breakdown or weather.

For example:

Day1: Darwin to Katherine - 317km solar

Cars not reaching Katherine or having trailered to Katherine by end of Day 1:
Day 2: trailer to Tennant creek - 670km + any distance not covered on day 1.
Day 3-4: Tennent to Alice - 510km solar
Cars that reach Alice without further trailoring before the end of Day 4 can continue driving.
Otherwise.
Day 5: Trailer to Coober Pede - 680km
Day6-7: Coober Pede to Port Augusta by 5pm - 522km solar
Day 8: Sunday trailer to Adelaide. - 300km

Cars not reaching Tennant Creek by 14:00 on Day 3, trailered or not:
Day 3,4: Trailer to Alice, 510km + distance to Tennant at 14:00 Day 3.

Cars not reaching Alice by end of Day 4, trailered or not:
Day 5,6: Trailer to Glendambo - 932km + distance not covered to Alice, 2 days
Day 7: Glendambo to Port Augusta - 290km solar
Day 8: Sunday, trailer to Adelaide. - 300km

Trailering to Glendambo may seem a little harsh, but if a team wants to trailer to Coober Pede they had better start trailering before Alice, to reach Alice before sunset on day 4. The next day will be a long trailer drive from Alice to Coober Pede (680km). A team wanting to drive to Coober Pede should trailer the remaining distance to Alice by the end of day 4, so they can drive the solar car out of Alice at 8am Day 5.

Cars not reaching Coober Pede by end of day 5 on trailer, or 13:00 day 6 without trailering:
Day 6: Trailer to Coober Pede, Start when they arrive up to 13:00
otherwise trailer to Glendambo by end of day 6 (200km trailer)
Day 7: Glendambo to Port Augusta - 290km solar
Day 8: Sunday trailer to Adelaide. - 300km

Cars not reaching Glendambo by end of day 7, trailered or not:
Day8: Trailer direct to Adelaide. 590km + distance to Glendambo.

Obviously, the control closure times would be based on these trailering requirements.

Officials may still allow a solar car to proceed even if they miss one deadline, if they have not missed any previous deadlines.

This strategy does not allow for solar car driving on Sunday, ie a 7 day race. However I believe a better strategy would allow some driving on Sunday while still allowing time for team to reach the awards ceremony on Sunday night.

I believe a new official finish line should be opened in Port Augusta Friday morning (day 6), so that cars that cannot make it to Adelaide by the time the road closes for solar cars (Friday 5pm) can do a ceremonial finish in Port Augusta rather than wasting time in Adelaide. Solar cars could simply be parked in the tents in Adelaide on Sunday when they arrive on their trailer.

A team must drive about 390km each day to reach Port Augusta by the end of Day 7. They would pass Katherine (317) by the end of day 1, pass Tennent Creek (988) about an hour before 14:00 on day 3, reach Alice (1498) about an hour before the end of day 4, reach Coober Pede (2178) around 12:00 day 6, Glendambo (2430) about 10:00 Day 7, and finish in Port Augusta (2719) at 5pm Day 7.

By Dunmara check point, about 1/2 the field were on target to achieve this, and all the remaining cars that had not trailered were close. 25 cars reached Katherine before the end of Day 1, all these cars were on track to do 390km on day 1, 12 cars didn't make it before the end of the day.

A car with a 1kW array, given minimum average WSC sunshine (6.5 Kwh/m2 per day) and a 4.5kWh battery would have 50 kWh to use in 7 days, at an average cruise speed of about 50 kph, with minimal time for stops and no breakdowns. To complete the distance the car would need to achieve 18.4 Wh/km, or 920W at 50 kph.