How to calculate my ETA?

stick to around 50-51mph avg on calculator. dived miles into hours. then add 2 hours to the total

 

Depends on where in the USA you are and destination. I use a very slow ETA method myself always leaving more cushion for unexpected delays or for my super lazy driving. 800 miles in my slow truck with 9 hours left today would be about 450 driving miles so I'd have plenty of time to find parking not running out of time.

Id expect my ETA to be 11:00am the next day approximately with wiggle room using your 8am time now with 9 hours left scenario.

 

First off remember the "E" in ETA means estimated. This is not an exact science. Your average MPH used to figure time is never going to be the same across every situation. If I am having to deal with rush hour traffic say in Atlanta I might have to add an hour or more to a trip that might only take maybe 30 minutes at 2 AM. I always used 55MPH when I gave an estimate. Then added or subtracted based on my location and time of day! This topic is one of those things you will learn with experience. Your milage may vary!

 

I add a half hour to the ETA that Google Maps shows, plus any planned stops (fuel, food, etc).

 

Dispatchers often use 50mph to calculate your arrival time. The low number is used to allow for delays, fueling, etc. They don’t calculate down to the macro level that you can since they don’t know all the details as you do for the trip. How many stops you’ll make, congestion, time of day, how many breaks you need, etc.

This is what I do. I calculate how many miles for the trip and divide by 60 average. The average may go up or down depending on location, etc. Then I add 30 minutes per fuel stop, my 30 minute break, miscellaneous breaks I’m going to take, plus buffer time depending on travel factors. I have gotten very accurate results with this method.

 

If the 800 miles is mostly interstate, and you are efficient and drive about 65 MPH, you should be able to use 60 mph as an average, plus a 10 hour break and a 30 min break for every 11 hours. That would be the soonest you could get there. Don't forget to calculate any time zone changes at the end. Also add in your pretrip inspection time (in this example I did not add them).

Using your example:

Time 8+9+0:30= 17:30

800-(9*60)= 260

So day 1 ends at 5:30 and you will have traveled 540 miles

17:30+10=27:30--24 = 3:30 is when your 10 is up

260/60 = 4 hours 17 minutes

3:30 + 4:17 = 7:47

Your ETA is around 8am if you take exactly 30 min and 10 hour break, and your arrival is in the same time zone. If different time zone, adjust this ETA accordingly. If your new, just to be conservative should add a couple hours for fuel, bathroom breaks and traffic, etc

To get a better ETA buy a top of the line Rand McNally GPS and it will incorporate speed limits and it also looks at your trucks speed history and provides an extraordinarily accurate ETA, which you will simply need to add your break times in. You can quickly transcribe this to dispatch. It is also less probe to math errors that doing these calculations in ones head sometimes yield.

Garmin only looks at speed limits so the ETA is very inaccurate if you are driving a 65 mph truck on 80 mph roads for example. So don't use Garmin's ETA imo.

 

This is a topic where there are no wrong or right answers. For me, I never figured my stops along the way. One thing though when it comes to establishing an ETA with your carrier is to be mindful of that ending. For example, I used 55MPH. a 1000 mile trip would take me on average 18 hours. Since I normally got about 540 to 580 miles a day I would then calculate my 10-hour break into that time. If I left Atlanta this means I am going to be about 450 miles from my final when I start day 2. Because maybe as much as 90% of my driving time is shot when I get to my final I also don't have a lot of 14-hour clock left either. Now, this is where trip planning comes into play! I yanked reefers, my normal detention time was on average 3 to 4 hours. I hope at least some of you are getting my point. In a 1000 situation, I have already planned that end of day on the 2nd day and also my dispatch knows that most likely I'm out of hours until the 3rd day. This trip planning thing somehow gets forgotten about with regard to ETAs etc. It is also the beginning of a nightmare for a new driver!

This topic reminds me of something I once heard an old Navy Blue Angels Boss say to me at NAS Oceania several years ago. He said when the team first starts out they are not as close together as they are toward the end of that season. This is because precision flying must be developed over time. This also applies to trip planning. Relax, if your carrier is breathing down your neck for you to be precise tell them to go pound sand you will get there when you get there. ETA is but a part of planning a trip, don't get so lost in getting there that you lose sight of what happens after you arrive!

 

One thing to bear in mind, try to give realistic etas, your dispatcher IS looking out for you by trying to figure out a reload on the other side. If you give an eta and then miss it by 4 hours, you might not make your next planned load, which the dispatcher has already promised someone you would pick up, this makes THEM look bad, it makes YOU look bad, and worst of all, it loses you money because it now means you might have to sit overnight before you get the load, or sit waiting for them to find a different load that works.

 

Im in the "50 mph" crowd. Usually a very conservative estimate. I would rather beat my ETA by a couple of hours than miss by 2 hours. As stated previously, you'll get better at it with more experience. In general, I plan my trips at 500-550 miles per day. Those are about the same numbers my company uses when planning our loads.