|
MEASURING HILLS BY THE TONS YOU PULL YOUR HORSES KNOW A HILL'S REAL HEFT By Bob Loehne
For the past year we have bandied about with our video claiming that Saluda is America's Steepest Class-1 Grade. Frankly, I expected to see a challenge or two taking shots at our claim, but as yet no one has. We often have talked about percent of grade and simply used that rather ambiguous figure as the measure of each hill's might. Interestingly, railroads don't pay a lot of attention to a percent of grade figure for their operational planning. Let's take a look at three Southern grades and the respect SR and NS have paid them over the years. Saluda, NC - Average grade about 4.7%; max perhaps 5.4%. A number of people say though steepest, it is not toughest to climb. Andrews, NC - Red Marble Mountain is a bear to climb from Nantahala to Topton; Average grade maybe 4.4%, max 4.8%. Balsam, NC - Balsam Mountain, home of highest railroad station east of Rockies; average grade about 4.0%, max 4.5%. After steepness, track curvature plays the greatest havoc with uphill trains. A 10° curve increases the apparent grade by 4/10 of one percent; an S-turn with two 13° curves adds one full percent. Of these SR inclines, the RR gives more respect to the climb over Red Marble Mountain, which is notorious for its continued winding turns. On Saluda, the bend at Sand Cut (3% grade) is the hill's only tight turn. Let's look at the 1986 NS Carolina Timetable #2 to see how Saluda compares with Balsam and Red Marble (Topton).
DIESEL UNIT RATING IN TONS
* Info from Mr.
Richard Kimball,
Notice that the drive up Red Marble from Nantahala Gorge has the lowest rating. A GP50 could haul a 565 ton train up Saluda, but it would have to off load 15 tons of cargo to haul the same train west up to Topton. That's what the book says. What about the engineers? I've talked to several and they are in virtual agreement: Saluda is dangerous, always a heartbeat away from a runaway. But Red Marble and Balsam are both worse! Given the choice, they were unanimous in their preference to run Saluda. But this is a different age for those old Murphy Branch grades. The line fran Dillsboro (as far southwest from Asheville as Saluda is southeast) was transferred to the Great Smoky Mountains Railway which operates the line to its end at Murphy. While NS allows no passenger activity on Saluda, GSMR treats excursion passengers to the delights, thrills and smoking brakes of the steep Red Marble grade. To give you an idea how different engines have been classed for the grind up Saluda, I used several old NS and SR timetables to create the following chart going back to the 40's.
ENGINE UNIT RATING IN TONS
I find it amazing that for all the extra wheels that come with an Ls-2, it could take only 50 more tons over Saluda than Mr. Patterson's helper or 15 tons less than an Don SD-35 or a GE 830-7A. For normal freights in the 50's and 60's the SR ran sets of 5 or 6 F-units (Biddix' crash had six) over Saluda, while from the late 60's to 80's railfans mostly saw SD35/40/45's. Now, officials call for the hi adhesion 6-axle END SD-50/60 and GE C39/408 for most trains. Interestingly, because 2 or 3 of these units together have just one quality source of brake line air, engineers prefer 3 SD-40's for 3 great air supplies. |
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||