mmarshall

Although, I learned mountain driving and grade-control in a number of places in the Central Appalachians, here's a good YouTube video of one of my favorite stretches of highway............the LONG, three-and-a-half mile descent, at an average 10% grade, of U.S. Highway 40 (the old National Road) from the top of 2500' summit of Chestnut Ridge into the valley towns of Hopwood and Uniontown. Chestnut Ridge, the last of the Allegheny ridges as you drive westward on U.S. 40 through MD and PA towards Ohio, is a rather high and rolling plateau on the east side, but, on the west side, has a dramatic, steep drop-off and a good scenic view at the Point Lookout stop. (I did a term paper in college, BTW, on the Appalachians)

This is THE grade where I learned the art of downshifting, engine-braking, and speed-control on long descents, more than any other (obviously by necessity). Although not particularly long or high by Western Sierra/Rocky Mountain standards (the Pikes' Peak Road, for example), by Eastern standards, this is quite a dangerous stretch, especially for heavy trucks (and this area has many coal trucks from the local mines). Large trucks are required (by signs) to come to a complete stop at the top, downshift into their absolute lowest gear, and maintain (if possible) 10 MPH all the way down. An emergency runaway truck ramp is built into the lower part of the mountain...you'll see it in the video.

Some of you who have driven in the Rockies may not find it a big deal, but this is quite a hazardous stretch of road by Eastern standards, and has resulted in a lot of accidents and deaths over the years. I've seen some Appalachian mountain roads that are much more curvy and winding (particularly near Skyline Drive in VA), but none this long and steep combined (except maybe for Mt. Washington in NH)

http://www.youtube.com/watch?v=AdxHrtANxC4

Here's some more views...and one from the bottom looking up:



http://www.city-data.com/picfilesv/picv8934.php

(this image would not post)

SLegacy99

I lived in Altoona for 2 years and was actually thinking today how much better I liked living in western/central PA as opposed to the Philly burb I reside in now.

MrG4Life

iTrader: (14)

There pretty serious about that speed limit for trucks and buses. There is a 10MPH speed limit sign like every 100 yards or so. Maybe even less.

geko29

The road is so wide it's tough to see the grade in the video until the surrounding area opens up towards the end. But I've been on quite a few roads like that, though most were narrower. I forget where it was, but when I was growing up, we were on vacation in a '78 plymouth (don't recall the model), and coasting with the big 318ci (5.2L) V8 in second gear, my dad still had to get on the brakes pretty solidly every 10 seconds or so to keep it under 60. It's tough to imagine doing that in an 80,000 lb truck, even with an exhaust brake (though obviously they help immeasurably).

mmarshall

There are some pretty interesting stretches not far from Altoona, too. One is U.S. 30 going up and down the Allegheny front...the long, curving hill where the old Steamship Hotel used to be before it burnt down. It has some sharper curves than the Chestnut Ridge descent on 40 (including one near-hairpin), but doesn't seem quite as steep for quite as long. That Chestnut Ridge descent is a monster.

Just a couple of miles from U.S. 30, the PA Turnpike also makes an even longer, 6-7 mile winding descent from the tunnel at the top of the same Allegheny Front, but is much less steep...it's a piece of cake. It trades more distance for a much flatter grade.

mmarshall

It averages 9-10% for three and a half solid miles all the way down from the very top, which is considerable, especially for heavy trucks.

And if you think that road is tough now, just imagine what it was like many decades ago, when it was only 2-lanes, and cars were less-reliable. There was a rest stop, with water/engine coolant, about halfway down for cars going down the hill with overheated brakes and going up with overheated engines.

Here are some old postcard shots:











Modern trucks have not only downshifting but the "Jake Brake" as well....I assume that's what you mean by the "exhaust brake".

On the Tru-TV/cable shows about the Ice Road Truckers in northern Alaska, they show the use of the Jake Brake going over slick roads in the Addington Pass (Elev. 4690) in the Brooks Range between Fairbanks and Deadhorse.

mmarshall

Yes, even on a road this wide (4 lanes, divided) in a regular 3000-lb. car, never mind a heavy truck, this grade still scares the hell out me every time I've been on it. I downshift, use very light pedal pressure on both gas and brakes (when needed), and carefully control my speed without burning up the brakes, keeping it to about 45 or so.


Even with this long, steep grade (and it's not really that dangerous if you use common sense and a little care), it's still a fun trip on 40 across the Mountains.....unless you're in a hurry, it sure beats the PA Turnpike for keeping you awake, and doesn't cost any tolls either.

geko29

Jake Brake is a brand of Exhaust brake made by Jacobs, much like Xerox is a brand of copier. It works by almost or completely cutting off the exhaust (some modulate, some do not), which makes the engine operate in reverse. Since an engine is essentially an air pump, restricting the exhaust puts the compression stroke on the exhaust side instead of the intake side. This gives you an engine braking power that is somewhere between 60 and 80% of the engine's peak torque rating. Multiply that with gear reduction in the transmission by using a low cog, and you have an absolutely massive amount of braking power, without using the service brakes.

mmarshall

Thanks. I had a rough idea of how the Jake Brake worked, but, not being a trucker, didn't know the details.

trukn1

Oh goodness,,US-40,,I was JUST on this road last week. The stories that I could share about this particular road are not for the weak at heart. Trust and believe, that as wide as it LOOKS in the video, it really is NOT that wide in reality. Think of your average 2 lane road with no shoulder on either side and you pretty much have an idea. Oh and you have to share it with truckers, such as myself, who are working hard to control up to 80K lbs of truck, decending down the grade, which for the rocord is 9% for 3 miles, all while trying NOT to burn up the brakes doing so. As Marshall stated,,it is an adventure. Yeah, it is a cheap way to get around the Pa. turnpike and over to I-70, just DONT SLEEP on this road b/c it is trickier than it looks. I could name several roads which would offer you an adventure. US322, Just North of Lewistown, Pa,,,skirting the Laurel Creek Reservior is another "fun" road to drive with a 7% grade on the mountain for about 5 miles. Just 1 of MANY I could name. LOL!!

IS-SV

Challenging and unique road, especially for the truckers. Good perspective Trukn1!

I8ABMR

I have said it before and I will say it again. Give me a Ferrari 458 Italia and an open freeway and let the smiles begin