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From: John De Armond
Newsgroups: rec.outdoors.rv-travel
Subject: Re: The Mileage Miracle
Date: Fri, 11 Jul 2008 06:57:51 -0400
Message-ID: <>

On Thu, 10 Jul 2008 10:58:00 -0500, Geoff Lane <geoff@nospam.invalid> wrote:

>Lone Haranguer <> wrote in
>>> I repeat my earlier post. It is my experience that fuel savings can
>>> be made by following two seconds behind a big rig at 90 km/h (56
>>> mph). In my case, the first time I tried it I got about a 12%
>>> increase in mpg compared to maintaining the same speed without
>>> "drafting".
>> And some people think there is an acceptable risk when robbing banks.
>> LZ
>You're confusing me here. What risk is involved in following two-seconds
>behind a heavy? FYI, that's the government minimum recommended separation
>over here.

OK, let's say you're bopping along 2 seconds behind that semi up ahead at 60
mph.  You're crossing that 29 mile stretch of I-10 in LA that crosses the
swamp, is built on stilts and has no shoulders.  There's a guy in the left
lane creeping past you.

Just as the guy in the left lane gets up even with you, out from under the
semi pops a 15 ft length of 10" I-beam that dropped off a truck farther up
ahead.  The semi cleared it easily enough but his tire nicked the end of the
beam and now it's skated sideways across your lane.

What are you going to do?  You can't react and stop in 2 seconds.  There's no
shoulder on the bridge so you can't go right.  There's a car next to you so
you can't go left.  What ARE you going to do?

I saw the remains of just about that scenario on that very stretch of highway.
The I-beam was still in the road.  The car was in the swamp 20 or 30 feet
below.  At least the parts that weren't still laying on the roadway.  There
was no ambulance present so either they'd already hauled the guy away or it
was obvious that an ambulance would do him no good.  I suspect the latter
after seeing the damage to the car.

Two seconds' following is fine when you're behind another car that you can see
around and over.  You can see what's going on ahead at the same time the car
in front of you does.  But 2 seconds behind a semi that blocks all forward
view is a death wish in my book.


From: John De Armond
Newsgroups: rec.outdoors.rv-travel
Subject: Re: The Mileage Miracle
Date: Sat, 12 Jul 2008 05:49:44 -0400
Message-ID: <>

On Fri, 11 Jul 2008 07:25:45 -0500, Geoff Lane <geoff@nospam.invalid> wrote:

>If you meant that the I-beam was already stationary, it is unlikely that
>the truck you're following wouldn't hit the brakes, and so you'd already be
>on the anchors before the I-beam came into view. Again, the chances are
>you'd miss it.

Why do you think that I'd brake?  I certainly don't and I'm the truck driver.
I'm NOT going to swerve to avoid it, even if that means hitting it, because I
know that a roll-over is MUCH more serious than a cut tire or two.  At most,
I'll lift the throttle and let my Jake scrub off some speed.  That does NOT
activate the brake lights.

Besides, I'm following the vehicle in front of me at a sufficient distance
that I have plenty of time to decide what to do and that includes stopping
rapidly.  If you're in my blind spot (you will be at 2 seconds back) then too
bad for you.

All you're doing now is trying to rationalize away that really stupid post you
made.  If you want to draft my semi 2 seconds back then more power to ya.
Doesn't affect me a bit.  The first time I straddle a dead deer or I-beam or
tire or whatever and said object takes you out, that'll just be one less
stupid car driver on the road that I'll have to dodge in the future.

BTW, you'd be absolutely amazed at how fast a semi can stop in an emergency.
We seldom use our brakes very hard because that causes unpleasant things like
load shifts, but the brakes are there if we need 'em.  If you're tailgating
back there, this is what will happen.  The trailer tandems unload from weight
transfer and the air bag suspension lifts the rear end.  Your little 4 wheeler
slides right up under the dock bumper until your windshield hits and a second
later, the trailer weight shifts back, the rear comes down and that dock
bumper becomes a guillotine.

Chop chop.


From: John De Armond
Newsgroups: rec.outdoors.rv-travel
Subject: Re: The Mileage Miracle
Date: Sat, 12 Jul 2008 17:22:08 -0400
Message-ID: <>

On Sat, 12 Jul 2008 15:48:40 -0400, Thats Me <yqcbbf@whab.pbz> wrote:

>I was taught to scan the road, Near, ahead, near again, left mirror,
>dash, right mirror, rinse and repeat.
>Two seconds is enough time for the average situation encountered on
>the road but for those that do not scan ahead the situation will be on
>them before they can adjust for changing road situations.

I agree with you and the guide about the 2 second rule AS LONG AS YOU CAN SEE
AHEAD OF THE NEXT VEHICLE!  That's the critical part.  That condition doesn't
exist with a semi, a large coach or a bus.

I'll come clean here, I used to be a drafter in my foolish youth.  I'd
sometimes get close enough to read the brand name on the dock bumper.  I also
got the tee-total sh*t scared out of me and some damage done to my car.  "Duh,
dumbass", I says to myself, "Wake up and smell the coffee".

I spent a lot more time back at a more "reasonable" distance, on the order of
what we're talking about now.  I STILL had the crap scared out of me by road

Following a large vehicle like that causes a mesmerizing effect.  It does to
me, at least and I suspect that I'm not unique.  You get in the zone staring
at the same thing - the back of the truck - mile after mile.  The same thing
can happen driving a semi and using the industry-recommended
truck-length-per-10-mph following distance. (I didn't stay that far back
because the effort was futile.  Some other vehicle would plug the gap.  But on
the interstate my following distance was more like 3-4 truck lengths.)

It takes a certain amount of time to come out of that state when something
happens - GPS beeps that your exit is upon you, blue lights appear in the
distance, debris comes from under the truck ahead, etc.  That time has to be
figured into a person's "normal" reaction time.

I've been in just that situation during my foolish drafting days and not just
when I was kissing the dock bumper.  An interstate gator pops from under the
truck you're drafting.  Your lizard brain that is doing the driving sees it
but it takes a second for the image to make its way to your conscious self.
Only then can you react.  I was lucky that the gator wasn't a whole wheel's
worth and that it slid over toward the shoulder enough that my feeble evasive
maneuver was enough.

Well, I've said more than enough on the subject.  I just hate to see stupidity
presented as something to be proud of or emulated, as our canuck poster did.
I'll shut up now.


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