The Great Payload Mystery

[slowmover]

Originally Posted by uncle_bob

Hi

Just as things like spacing distance matter, so do things like driver fatigue. Packing up the campsite and dogs starting at midnight to roll out before 1 AM (in order to drive in less traffic) has it's impact. If this is the time of day you normally sleep .... that has an effect. There are parts of the country where things don't go nuts starting at 6AM. Equally, there are parts of the country where 6AM to midnight is going to have "crowded" roads.

Another minor issue - as we get older, some of us don't have quite the night vision we once had. Glare and the like are more of a problem. Driving in the middle of the night becomes a bit more of a challenge than it once was.

Lots of variables .....

Bob

Why I recommend the use of GAISMA. Departure no earlier than 1/2-hour prior to sunrise (if not headed directly east).

The daily trip plan should have been done yesterday. Stops already in GPS device. The day broken out into a series of legs to accomplish, one by one. Rest areas or similar for the two hour / 100-mile mark 15" break. The 60" Lunch / Fuel stop[s] at the four-hour (200-mile) mark. Time on the road trumps distance. Etc.

As with best hitch-rigging / TV tire pressure, the planned use of the clock avoids fatigue. Equates with best results.

300 or 3 o'clock.

It was harder to cover the same miles way back when. Or in Mexico. The optimal time recovery times haven't. (Thus avoiding the NA mega-regions for planning overnights).

The gun is always loaded. Prudence, with best habits.

.

[Andrew T]

Another interesting tidbit.
A Mercedes GL in Europe has approximately 500 pounds higher rear axle capacity if you are towing and do no exceed 62 MPH. GVWR does not change but obviously would be exceeded.

In some ways this makes sense vehicles designed for a certain load at autobahn speeds would obviously be able to carry more at a lower speed.

[uncle_bob]

Originally Posted by slowmover

Why I recommend the use of GAISMA. Departure no earlier than 1/2-hour prior to sunrise (if not headed directly east).

The daily trip plan should have been done yesterday. Stops already in GPS device. The day broken out into a series of legs to accomplish, one by one. Rest areas or similar for the two hour / 100-mile mark 15" break. The 60" Lunch / Fuel stop[s] at the four-hour (200-mile) mark. Time on the road trumps distance. Etc.

As with best hitch-rigging / TV tire pressure, the planned use of the clock avoids fatigue. Equates with best results.

300 or 3 o'clock.

It was harder to cover the same miles way back when. Or in Mexico. The optimal time recovery times haven't. (Thus avoiding the NA mega-regions for planning overnights).

The gun is always loaded. Prudence, with best habits.

.

Hi

I guess what I'm saying is that if you live up here in the north east, over just about any practical route / most of the year -- if the sun is up, there's enough traffic to notice it. The spacing you would *like* to maintain is not going to be the spacing you *can* maintain. Some routes are packed tight enough that the whole concept of spacing is out the window.

Yes, I just got back from a little drive on I-81 and am a bit grumpy ... Don't get me started on never ending construction projects ....

Realistically there are only a few practical alternatives if you live around here:

1) Move to another part of the country

2) Fly and stay in hotels

3) Only drive very late at night (after midnight)

4) Accept that you *will* be in traffic a lot of the time.

I'm not sure there is another option up in this area. Once you are across the Mississippi, sure, things are a bit different..... errr... welcome to LA ... ok, different most places.

By no means am I suggesting spacing is a bad idea or that getting out of a blob of traffic is a bad idea. Driving down an empty highway 6' off the other guys bumper is stupid. My point is that it is just one technique. Like any technique it doesn't work in all cases. I see people get hung up on "this is THE right thing". It does not just when driving. It happens in a lot of areas. Always better to understand that there are tradeoffs.

Bob

[slowmover]

Originally Posted by uncle_bob

Hi

I guess what I'm saying is that if you live up here in the north east, over just about any practical route / most of the year -- if the sun is up, there's enough traffic to notice it. The spacing you would *like* to maintain is not going to be the spacing you *can* maintain. Some routes are packed tight enough that the whole concept of spacing is out the window.

Yes, I just got back from a little drive on I-81 and am a bit grumpy ... Don't get me started on never ending construction projects ....

Realistically there are only a few practical alternatives if you live around here:

1) Move to another part of the country

2) Fly and stay in hotels

3) Only drive very late at night (after midnight)

4) Accept that you *will* be in traffic a lot of the time.

I'm not sure there is another option up in this area. Once you are across the Mississippi, sure, things are a bit different..... errr... welcome to LA ... ok, different most places.

By no means am I suggesting spacing is a bad idea or that getting out of a blob of traffic is a bad idea. Driving down an empty highway 6' off the other guys bumper is stupid. My point is that it is just one technique. Like any technique it doesn't work in all cases. I see people get hung up on "this is THE right thing". It does not just when driving. It happens in a lot of areas. Always better to understand that there are tradeoffs.

Bob

That version of realistic isn't much fun, is it? Sort of hits against the desire to travel at all by road.

Believe me that I understand. IH81N is kinda nice till I leave Virginia. Not all all in your corner of the woods. There are plenty of others.

Spacing is barely speed-related. It may mean backing off more often than accelerating forward. If one is on a highway with traffic above posted minimum , it's just part of the game.

Use the clock. Plan the stops. Maintain the spacing. Ones average speed for that day may not be great. So? It's otherwise been optimized.

Vehicle spacing is the control on all other driver actions. It's one of those statistical verities.

If there's to be a "tradeoff", then what's the emergency stopping distance?. Full stop.

200' is a fraction of that, isn't it? (And doesn't include the distance of recognizing a danger).

But "you" (whomever) can't maintain it? (Not buying that).

"You" do (at least) get a touch heavy on the brakes when having been passed by someone who then intrudes within the 100' space, right? (Since just dropping the throttle means the TT is free to act up).

(Don't answer. Try it. Practice.)

There comes a point one can pretty easily predict "who" will cut back over too soon. Most are under 100', but some are terrible. (None have brains. My favorite are those who, having passed the big truck truck bow wave then just sit in the left lane "long enough" -- having made no further progress ahead versus my speed -- and, sure enough, here they come back over. Too damned close, but they were too long in left lane!

Or, that the cretins get points for passing combination vehicles. Everyone knows about that, right? Pass, then slow. When enough other sub-morons have formed a pack in both lanes just ahead of the combination vehicle where a few minutes before no vehicles were present, all are eligible for 20-cents off the next fast food order. Yeah!! I love Leapfrog!!

Space maintenance gets easier with practice. Both the distance and the predictions. Use the tool of average speed. Engine run time. There just isn't that much difference.

And, sometimes the spacing is well to the rear of me. That makes the idiots bearable once they're a quarter-mile ahead.

.

[uncle_bob]

Originally Posted by slowmover

....

Spacing is barely speed-related. It may mean backing off more often than accelerating forward. If one is on a highway with traffic above posted minimum , it's just part of the game.

Use the clock. Plan the stops. Maintain the spacing. Ones average speed for that day may not be great. So? It's otherwise been optimized.

Vehicle spacing is the control on all other driver actions. It's one of those statistical verities.

If there's to be a "tradeoff", then what's the emergency stopping distance?. Full stop.

200' is a fraction of that, isn't it? (And doesn't include the distance of recognizing a danger).

But "you" (whomever) can't maintain it? (Not buying that).

"You" do (at least) get a touch heavy on the brakes when having been passed by someone who then intrudes within the 100' space, right? (Since just dropping the throttle means the TT is free to act up).

(Don't answer. Try it. Practice.)

....

.

Hi

If I head out on I-81 right now (it's 9:45AM local time) and try for 200' (roughly three 18 wheeler lengths) *consistent* spacing, it simply isn't going to happen. There is no speed / no technique that will let me do that. Even 100' is doubtful. The mix of traffic likely will be running between 45 and 85 MHP depending on which lane and who.

So what's going on? I can sit at any of a number of locations and watch the traffic go by while munching on a burger. Blocks of 20+ cars / trucks all spaced at *maybe* one truck length apart? Yup, here comes another one. Lots in the right lane, some in the left lane. Second block is maybe 10 seconds behind that one.... and on and on...There's just that much traffic on the road.

So, will you *always* be packed? No, but each time one of those blocks of traffic swerves past you, you will be in tight. You *might* have spacing control for 5 seconds. Then you are right back packed in. >80% of the time, the guy passing you makes the decision. (or you pull up tight to the vehicle in front of you, which is the same thing).

The result of all this *is* quite predictable and it does happen with some regularity. It happens a bit more often in the winter (and is blamed on snow). So I'm not claiming this is a good thing at all. It's simply one of the joys of driving around up here. Worse news - this local area isn't "bad" by the standards of the northeast.

Is this just a "choke point"? There certainly are areas like that. They most certainly mess up traffic flow. We have construction zones every 20 miles or so forever and ever. Last road trip, they ran like that from here to the Indiana / Illinois boarder.

To me a choke point is a slow down for a 5 mile stretch that then opens up once the "obstacle" has been cleared. The stuff I'm more concerned about here goes on for hours of driving time. The situation extends over most of the daylight hours.

Bottom line is, when I'm headed out for a "vacation" these are the conditions at least part of the drive is made in. Years ago, yes I could schedule or route around it. These days, around here ... not so much.

There's a *lot* of traffic on the road these days.

Why gets into politics and maybe metaphysics. We move a lot of stuff by truck and move it over long distances that way. We live further and further from our jobs. My mom *never* drove me to the number of "required" events kids head off to these days. At the same time, new road construction is not going at the rate it did in the 50's, 60's or 70's. Road maintenance never was good, it's worse now. With more packed roads and frustration, driver behavior deteriorates. Seemingly rational people will tell you that driving 20 MHP over the speed limit is "how it's done today". I don't even want to think about the number of "20 hours straight behind the wheel" stories.

It's crazy out there. My answer is *not* to simply hunker down in my bunker. I'm not going to take crazy risks. I'll drive as safely as I possibly can. I will get out and do stuff. What I can control, I will control. What I can avoid, I most certainly will avoid. Sunday afternoon coming back from the beach - not so much I'm also not going to freak out / panic when things do get a bit weird.

Bob

[PKI]

Bob - commuted for most of my adult life. Believed as you are professing. If you don't guard that space in line by closing up the following distance you will never get to work.

When we turned 55, we attended a senior safe driving class. The ex CHP instructor told us the same thing Slow is recommending. Slow down to maintain your distance. Just try it and you will see it works, he said.

Can't be true, I thought. So I set out to prove him wrong. Guess what? It is true. As you slow, someone will pass, and you slow a bit to open the gap, but you still move forward at a steady rate.

I don't do this well. Old habits are the devil to kill. But it is worth the effort to improve.

Try it. It works. Pat

[slowmover]

Thx, PKI. Looked impossible to me as well.

I agree with every point you've made, Uncle Bob. And I also resisted. When I wrote "statistical verity", that was your clue.

It's not about perfection in that type of traffic. If it's moving above the minimum, not stop-go, then it's possible to maintain that space. Even if it waxes and wanes. One is essentially 5-mph below others (rule of thumb). The flow ahead, around, and behind is markedly faster. Not a lot. But, enough.

I had a Proximity radar on a recent truck. Great feedback device. Told me distance and speed of vehicle ahead of me. Shortened the learning curve.

A dashcam is great (I'm told). But one doesn't want the radar, black box and confirming camera to tell the Safety Department just how bad one really is (Damned telematics, ha!).

Granted, my incentive (consequences) are greater. The difficulty is also higher.

I don't normally recommend following a big truck, but that the easiest 100+ feet to maintain that there is. In that kind of traffic (just be extra careful about complacency. An empty big truck with disc brakes can stop on a dime).

.

[uncle_bob]

Hi

My only real point is that people should not freak out. The details are not quite as significant.

I do agree that often the only practical answer to the case I presented is to fall in line and put up with the downsides that creates. You have more spacing control and slightly better confidence in what's ahead of you (since it does not change every 5 seconds). There's still the turkey that on occasion will decide to do this or that .... live with it, do not ram him.

Bob

[slowmover]

Freak out.

I've recommend applying a quantifying test or tests: brake and tire life. Do those last above 70,000-miles? I see over 100.

And inside of that, how often are really hard stops (or slowing) needed? For me it's about twice per year. Once every 50-60,000 miles. .

Short of having proximity radar as instant feedback, a metric. Some sort of touchstone to gauge driving changes.