Safer Drafting? - Fuel Economy, Hypermiling, EcoModding News and Forum

trikkonceptz · 06-18-2008, 04:21 PM

Well as its been said and proven so many times, drafting is an effective way to increase mpg. However it is very dangerous in everyday driving because of the close proximity you have to get in order to get effective gains.

In my driving however I have begun to notice that I get incredible FE gains when a tractor trailer passes me, even if for a moment. SO for the past couple of days I have done another non scientific experiment.

I began drafting the truck from the other lane. In other words, I stay one lane over and still maintain the 20-30 ft distance behind the rig. This keeps me off his ass and in his mirrors, so if he has to get over into my lane I just let up and let him and wait for the next truck.

As far as gains, my normal FE on hwy is roughly 47.5mpg, while side drafting it jumps to a whoping 58mpg+, I saw a steady high today of 67mpg on the scangauge.

So while not as dangerous, I see potential in this because apparently the broken air off the back of one of these monsters is about three lanes wide. So have fun trying it, just figured I'd share my results so far. Now good luck finding a trucker doing 60mph on a freeway.

Daox · 06-18-2008, 04:33 PM

I've heard this referred to as a surf draft. It is obviously beneficial and safer than following directly behind the truck. The downside of course is that your essentially creating a two lane road block while cruising. As usual, its hard to find them going as fast as you're willing to go.

Tony Raine · 06-18-2008, 05:20 PM

my best "safe drafting" technique so far has been my CB. some drivers are really cool about it (i think it gives them a little better mpg too). some aren't, and a cb is a good way to find out so you can avoid them.

i haven't tried "surf draft" yet, sounds a lot safer.

Who · 06-18-2008, 06:07 PM

In cycling, drafting like that with a cross wind would be called an echelon. Fortunately bicycle wheels can't penetrate a windshield like truck wheels can if they come off.

jamesqf · 06-18-2008, 06:32 PM

Quote:

Originally Posted by Who

Fortunately bicycle wheels can't penetrate a windshield like truck wheels can if they come off.

Because not many bicycles have windshields?

However, if you stop to think about the mechanics of a truck wheel coming off (a pretty rare thing), or the more common tread delamination or blowout, it would seem that directly behind the truck is going to be one of the safer places. If a wheel came off, it A) would have some outward momentum from wobbling against the lug bolts; and B) unless it was on the rearmost axle, would hit the wheel behind and bounce away to the side.

Who · 06-19-2008, 10:45 AM

jamesqf, and I wish it were a lot more rare. I'm familiar with 2 fatalities during a relatively short time period that were caused by lost truck wheels on a local section of freeway (QEW) that I frequently travel.

google ["truck tire" died windshield] or something along those lines.

Your post seems critical of mine. Am I wrong to mention safety considerations?

Lazarus · 06-19-2008, 11:16 AM

Quote:

Originally Posted by Who

jamesqf, and I wish it were a lot more rare. I'm familiar with 2 fatalities during a relatively short time period that were caused by lost truck wheels on a local section of freeway (QEW) that I frequently travel.

google ["truck tire" died windshield] or something along those lines.

Your post seems critical of mine. Am I wrong to mention safety considerations?

I saw the same thing in town on a 18 wheeler. The wheel came off at about 30 mph.

gteclass · 06-19-2008, 11:19 AM

Drafting is a great way to save gas and remember that its not just tractor trailors that you can draft. If you are in an economy car you can draft just about anything.

ebacherville · 06-19-2008, 11:26 AM

well driving is a risk no matter how you look at it.. your driving on a road with hundreds of other multi-ton objects traveling at 1/10 the speed of sound.. and many are piloted by MORONS.. Ill hide behind a 80,000lb semi and enjoy the added security of a added large brick wall like buffer against oncomming traffic and some added FE gain.. and risk a tire flying off.

ebacherville · 06-19-2008, 11:27 AM

Quote:

Originally Posted by gteclass

Drafting is a great way to save gas and remember that its not just tractor trailors that you can draft. If you are in an economy car you can draft just about anything.

Yeah those SUV's and vans make great cars to draft behind. however a semi allows you to follow further back and add some distance for safety.