Unlike many other rallies the Cannonball Runs have a legal objective that allows the rally to have a true winner. We received a lot of questions about this 61 mph objective used in the Cannonball Run’s including this years Great American Run. We will try to answer all the questions in this article.
What is the 61 mph objective?
The 61 miles per hour objective means contestants have to aim for a 61 mph average over the total distance of the rally.
How is the 61 mph measured?
To measure your average speed there’s three variables that need to be entered: the distance, your start time and your arrival time. The difference between your start and arrival time is called driving time. When you divide the distance by your driving time you get your average speed. During the Cannonball Runs also your odometer is reset when you start and written down when you finish, this is just to make sure you followed the designated route and not used in any calculations of your average speed.
In multiple day events a subtotal is made for every team on a daily basis. All these subtotals are added and make your final average speed. The subtotals are not weighted and your average speed over the total distance is therefor irrelevant.
Day 1: Distance 500 miles / driving time 7 hours = 71.249 mph – 61 = 10.249 mph variance
Day 2: Distance 400 miles / driving time 8 hours = 50 mph – 61 = -11 mph variance
Day 3: Distance 600 miles / driving time 10 hours = 60 mph – 61 = -1 mph variance
Total: 10.249 – 11 – 1 = -1.751 mph variance + 61 mph = 59.249 mph
If the averages were weighted the overal average would be: (500+400+600=1500) / (7+8+10=25) = 60 mph. But weighted averages are a lot harder to calculate and therefor not used during Cannonball Runs.
When calculating the average speeds or preferred arrival time remember to calculate the minutes to a percentage.
During this Cannonball Run a 2 hour mandatory stop was included in the average speed calculation. This lowered your driving time used for calculating your average speed by 2 hours.
Distance 500 miles / total driving time 10 hours (start 10am – arrival 8pm) – rest time 2 hours = driving time 8 hours = 500 / 8 = 62.500 mph – 61 = 1.500 mph variance.
Your average speed can also be limited by checkpoint opening and closing times. All checkpoints have certain opening and closing times if you start or arrive before or after opening times you will automaticly be assigned the opening or closing time for that checkpoint.
Day x: Distance 500 miles
Start checkpoint opening 9am – closing 10am. You left 11am
Finish checkpoint opening 5 pm – closing 7 pm. Your arrived 6pm
Actual average: 500 miles / 7 hours driving time (11 am – 6pm) = 71.429 mph – 61 = 10.429 mph variance
Calculated average: 500 miles / 8 hours driving time ( 10am – 5pm) = 62.500 mph – 61 = 1.500 mph variance
In this example the checkpoint opening and closing times work in your advantage and keep you closer to the 61 mph. But be careful the finish checkpoints opening and closing times are only announced on the mission card you receive at the morning checkpoint. So if you leave to late you might not be able to make it to the finish checkpoint with a 61 mph because the checkpoint already closed giving you a much higher average speed.
We hope this solved some of your questions, if you have any other questions please contact us!