Long a staple of amusement parks worldwide, wooden coasters fell out of favor with the emergence of modern steel coasters in the 1960s and looping inversions in the 1970s. A resurgence of wooden coasters in recent decades brought few innovations but plenty of headaches for parks that spent dearly keeping the high-maintenance rides from falling into disrepair.
Rocky Mountain's innovations utilized steel reinforcements to supplement wooden tracks typically held together by only nails, bolts and cross braces. The company's patent pending Topper Track (which replaces the top two layers of wooden track with steel rail) and Iron Horse treatment (which replaces the entire wooden track stack with a steel box) essentially function as rigid steel clamps around a flexible wooden frame.
"It's industry changing," Grubb said. "It's revolutionary."
The result is a smoother and faster ride that replicates the rambling and rumbling sensation of a wood coaster without the roughness that develops as the timber structure flexes with advancing age and weather fluctuations.
The iron exoskeleton also allowed Rocky Mountain engineer Alan Schilke to introduce steel coaster-like near-vertical drops, over-banked turns and barrel roll inversions to the wooden coaster vocabulary.
Schilke, who devised the Iron Horse track with Grubb, made his mark in the industry with his design for the prototype fourth dimension X coaster at California's Six Flags Magic Mountain while working for ride manufacturer Arrow Dynamics.
New York's Coney Island was home to several early looping coasters, including the 1901 Loop-the-Loop. Revolution, the first modern vertical looping coaster, opened in 1976 at Magic Mountain. The Corkscrew by Arrow Dynamics debuted the year before at nearby Knott's Berry Farm.
Rocky Mountain has been refurbishing aging Six Flags wooden coasters for several years, but it wasn't until the amusement park chain's Arlington, Texas park reopened the New Texas Giant in 2011 that the coaster community took notice of Rocky Mountain.
Originally built by Dinn Corporation in 1990, the $10-million rehabilitation of the New Texas Giant added a 79-degree first drop and beyond vertical banked turns along with a million pounds of steel via Rocky Mountain's Iron Horse treatment.
Coaster fanatics are eagerly awaiting the summer 2013 debut of the world's only inverted wooden coasters: Iron Rattler and Outlaw Run.
"The ride is completely different," Grubb said. "It's smooth as smooth can get."
The 1992 Rattler wooden coaster at Six Flags Fiesta Texas will be reborn as the Iron Rattler hybrid coaster with the Rocky Mountain Iron Horse treatment. The remade ride will remove the cliff-top triple helix while adding a barrel roll inversion and four beyond-vertical banked turns.
The $10-million Outlaw Run hybrid wood-steel coaster at Missouri's Silver Dollar City will feature a double barrel roll, a 153-degree over-banked turn and nine airtime hills along with Rocky Mountain Topper Track. The coaster also marks the debut of the new Rocky Mountain trains, which will reach 68 mph (the second fastest of any wooden coaster in the world) after descending an 81-degree first drop (the steepest of any wooden coaster in the world).
So if Rocky Mountain can build a wooden coaster with a barrel roll, might we eventually see a vertical loop, cobra roll, hammerhead, Immelmann loop or top hat element? Or possibly a launched, spinning, suspended, stand-up or winged wooden coaster?
"We feel we can put all the tricks in that steel coasters have," Grubb said. "Of course, we haven't developed them yet, but the potential is there. We talk about all kinds of different things."
According to Grubb, Rocky Mountain is in discussions about additional projects with Six Flags, which runs 13 amusement parks in North America, and Herschend Family Entertainment, which owns, operates or manages five U.S. parks: Silver Dollar City (Missouri), Dollywood (Tennessee), Darien Lake (New York), Wild Adventures (Georgia) and Elitch Gardens (Colorado).
Although Grubb refused to announce any park names or ride details, he did say Rocky Mountain has multiple projects planned for spring 2014.
Roller Coaster Database's Marden was decidedly less shy about picking his top candidates for Rocky Mountain makeovers: Cedar Point's Mean Streak, Six Flags Magic Mountain's Colossus, Knott's Berry Farm's Ghostrider, Busch Gardens Tampa's Gwazi, Wild Adventures' Cheetah and the Boss at Six Flags St. Louis.
Only time will tell what's next for Rocky Mountain, even if Grubb won't: "No comment," he said with a laugh.