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20 years in the Amusement industry

Part 16: Kings Dominion's Grizzly: This Wildcat Gets a 2nd of 9 Lives

(Above: Utilities layout, Grizzly, around 1998. Drawing by Brumfield)

As mentioned in part 3 of this series (“When roller coaster riding was blood sport”), the 1920s was the golden age of wooden roller coaster construction. Designers such as Harry Travers and Herb Schmeck designed and built some of the most terrifying coasters ever seen, even up to this day. Marketing gimmicks, including as having a nurse in the station (Crystal Beach Cyclone), rumors of death by fright (Coney Island New York Cyclone), and injuries such as chipped teeth, whiplash and blackouts only heightened the sense of real danger of these snarling pressure-treated beasts, and in many cases people impatiently queued up to ride even as an unconscious rider was pulled bleeding from a car. In one extreme case, a woman was killed on the Travers-designed Revere Beach Lightning on its second day of operation in 1927, yet people waited in line to ride even as her body was removed from the tracks.

In 1926 a Schmeck-designed wooden coaster called the Wildcat was built at the Old Coney Amusement Park near Cincinnati, Ohio. While records fail to show that a nurse was hired to stand in the station, or that anyone was seriously injured on the ride, it was an enormously popular ride until frequent floods from the Ohio River became too damaging (See undated photo at left of the Wildcat under water). In 1964 the Wildcat was torn down to expand the midway, then In 1968, Coney management began talks with Taft Broadcasting to buy the park and rebuild it on higher ground. Coney shut down in September, 1971; all the flat rides were moved to the brand new Kings Island near Lebanon, but unfortunately the remaining coaster, the Shooting Star, was demolished.

In 1980 Curtis D. Summers Engineering of Ohio tweaked the original Wildcat plans and rebuilt the ride in 1981 at Canada’s Wonderland in Vaughn, Ontario calling it the Wilde Beast. Further down south, in Doswell, Virginia, the soon-to-become Kings Entertainment Company-owned Kings Dominion decided that a “blast from the past”-style wooden coaster would be the perfect addition to accompany their original racing coaster, the John Allen-designed Rebel Yell, so plans for the old Wildcat were modified and updated even more by Summers Engineers, and soon construction began on what was to become the Grizzly.

(Summers was familiar already with the design of the coaster, as he had been originally hired by Coney Island to do structural work on both the original Wildcat and the Shooting Star.)

(Above: Grizzly structure section. Drawing by Brumfield)

Wooden roller coaster construction is the closest thing we have today to slave labor. It is tedious, back-breaking work, whether you are toting 20-ft-long treated 2x10 boards up and down hills, driving 20-d galvanized nails with a 22-oz claw hammer every 6” into rock-hard lumber, or hanging vertically while drilling thousands of 5/8” holes through 4x12 ledger boards, there is nothing easy. And it goes on, day after day, week after week, through the coldest, most miserable part of the year. I personally spent months walking up and down those hills with a heavy board on my shoulder, and driving hundreds and hundreds of nails. It is truly a version of hell.

Unlike a steel coaster, which is considered a “static” structure (designed to not move), a wood coaster track is considered “dynamic.” This is critical – wood has to be able to move, swell and shrink with the forces of the ride and the weather, or it would crack, split or shake itself apart. This feature is what gives the Grizzly that unsettling feeling that at any second it is going to blow apart, but in actuality it is incredibly strong. And anyone who has ridden the Grizzly can attest to that “holy cow what is keeping this train on the track anyway” feeling, because of the dynamics of the structure. It is quite brilliant in its simplicity.

Grizzly construction began once the area was cleared. Only necessary trees were removed to keep as much of a forest atmosphere as possible. Each footer location was marked, then dug, and concrete was poured after rebar cages dropped in, usually between 2-4 feet deep depending on the type of ground. A galvanized metal strap was placed in the concrete, protruding several inches out of the top of the footer. The posts will be bolted to that.

Wood coaster design may look random but it is very precise, with each and every board having a term and a purpose. Huge 6x8 posts were paired together (called “bents”) to the correct height, notched and bolted end to end flat on the ground. “Chords” (always parallel to the ground) and diagonal “braces” were nailed between them, then the bent was raised by a crane and bolted to the footer strap. “Ribbon boards” nailed loosely to one bent were swung up into place (always horizontal to the ground) and nailed to the next bent to keep them upright as they were raised. Ribbon boards are key to spotting structural deformations during operating season, and a board that suddenly splits during the season could indicate a much farther-reaching structural problem.

(I personally noticed one ribbon board vibrating excessively during the Grizzly’s first season, until it finally broke weeks later. It turned out a concrete footer 2 bents away had sunk about two inches. Once the footer was corrected, the board stopped shaking.)

At the top of the bent, a crane lowered massive 4x12 timbers called ledgers onto aluminum clips bolted near the tops of the posts. Carpenters laid down walkboards (a very important part of the structure, as not only do walkboards give carpenters, mechanics and inspectors something to walk on but they are the only reactive horizontal supports, tempering the structure’s side-to-side motion). The walkboards and the actual coaster track (or “laminates”) sat directly on top of the ledgers, but only the walkboards are nailed down.

So, wrap your head around this - a roller coaster track literally floats on top of the structure. There is nothing holding it down, not one nail. If one could find a crane big enough, they could literally lift the entire track off the structure and set it on the ground. This is true with every wood coaster – the track has to float, or again it would shake the structure apart. Seriously, I’m not kidding.

Once the walkboards were down the carpenters began nailing on the handrails. A supervisor who helped build the Rebel Yell told me once that he had to carry 20-ft long track boards up the first drop on his shoulder before the handrail was installed. “I had never been off the ground in my life,” he said of the experience of climbing 80 feet up with nothing between him and the dirt but a walkboard, “I was so scared I was crying.”

Handrails are not just there to keep carpenters and inspectors from crying – they serve as thrust members between bent posts. See? Every board has a name and a purpose.

Once the structure was under control, another team of carpenters came along and began laying down the actual track (2x10 boards called “laminates”). The train runs on layers of 2x10s 7 deep (or 9 deep in high stress areas), with 2 2x10’s offset on top (see illustration for clarification). This is the most mind- and body-numbing aspect of coaster construction: like worker ants, laborers carry and lay those 20-ft boards, then they are lined up in place, then 3 nails are driven every 6 inches. Then the next layer goes down, and 3 nails are driven every 6 inches. And so on and on and on and on, until all 7 (or 9) layers are down, all the way around the entire circuit. In a perfect world, that is around 140,000 nails, just in the track.

Specific rules apply to the nailing of the track laminates: only 20-d (or 20-penny) galvanized nails can be used. No nail gun can be used; only a hammer. If a nail is bent it must be removed and a new nail put in its place. At least 4 feet must separate joints in adjoining layers, ad nauseum. It is serious business, and takes a team of carpenters months.

Proper latitudinal spacing for the track laminates is critical, so 4x4 boards called “intermediates” are bolted underneath to the track laminates every 2 feet or so. Intermediates maintain the gauge with a 5/8” x 18 bolt to lock the plies and hold the track to proper spacing. They also help support the walkboard.

On Curves, the radius is cut into every board before it is nailed down.

While the laminates are put in, another team places other structural compression members, such as “batter braces” (designed to temper outside sway, such as around the fan curve), and “stompers,” which are extra supports (mini-bents) placed in dips (many stompers had to be placed where the Grizzly train exits the tunnel, as it quickly became apparent this was a very high stress area). Other structural supports such as guy wires are added, usually in response to observed movement during beta testing.

Am I killing you yet with boring structural details? Imagine being 75-feet in the air on a windy 18-degree day doing a 10-hour shift nailing these damn things together with no handrail beside you. And here you are complaining about sitting in a chair just reading about them.

(Above: Grizzly lap bar, wheel and track placement assembly. Drawing by Brumfield)

A wood coaster runs on three pieces of flat steel bolted to the laminates: the “road steel” is the primary steel, and is bolted on top of the laminates. The “guide steel” is placed on the inside of the top two 2x10 laminates and controls the side-to-side motion. The “upstop steel” is placed only on the tops of hills on the bottom of the offset of the top two laminates. This controls the up and down motion of the train, and keeps it on the track over camel humps. There are sections of the Grizzly where the road steel remains untouched after years of operation – over top of the tunnel is one such place. The train is going so fast that when it crowns that hill it runs only on the upstop track. This is completely normal. Trust me.

(Right: Nothing comes simple: Grizzly lap restraint assembly. Drawing by Brumfield)

One thing the Curtis Summers design did not count on was the Philadelphia Toboggan company’s decision to build the Grizzly cars like Sherman tanks. When the cars arrived around late February, 1982, they were the proper 4-person configuration as requested (unlike the Rebel Yell lighter, 6-person cars) but they were built of battleship-grade steel and aluminum, weighing far more than originally anticipated. PTC reportedly built them based on projections of speed, angle of curves and thrust, then doubled the safety factors just to be sure. The president of PTC told a KD maintenance supervisor that they were the “heaviest cars” they ever built. The cars also had solid couplings (unlike the Rebel Yell, which originally had spring-loaded couplings) and articulating rear ends to help absorb some of the impact of the sudden turns.

Early test runs showed the heavier cars added much more stress to the structure, especially where the train exited the tunnel and roared around the fan curve, so the entire summer of 1982 was spent adding extra stompers under the tunnel, and batter braces and guy wires around all the curves. You think the fan curve sways now, when you watch the train from the station? You should have seen it in 1982.

The Grizzly was also one of the first wood coasters anywhere to have a new type of brake, called a fin. A ¼” steel blade extended vertically on the bottom of each car, and was stopped via a brass-lined air caliper-operated “squeeze brake.” This was an improvement over the old style “slide” brakes (like the original Rebel Yell, which was converted in the mid-1990s), where the train was slowed and stopped by “mutton leg” boards lifting the wheels and sliding the train to a stop.

(Left: Grizzly lift drive lower sprocket, gear box and coupling)

Coasters run on electricity and compressed air. The ride will not turn on unless the sir pressure is up to a certain psi. Pressure is always maintained via holding tanks and pressure switches, so even during a catastrophic power failure the lift may shut off but the train can still be stopped if it leaves the lift.

One thing people do not understand about roller coasters is that once the train leaves the lift chain, there is nothing anyone can do to stop it. I remember watching a made-for-TV movie back in the 1980s that showed a power failure in an amusement park, and the roller coaster came to a stop out on the track. It drove me crazy – it cannot happen. Once the train leaves the lift it is under the control of gravity only until it stops into the first brake zone – which in a power failure, as mentioned earlier, is designed to stay closed.

There has been only one accident with the Grizzly, and thankfully no one was injured. Around 1997 the track swelled out of gauge during a dry spell, and over the tunnel the train somehow popped out of the track on the right side, causing the left side to drop down and skid on the running board. The train went all the way around the lower back curve like that, and the brake fin underneath struck and damaged every single intermediate. It had to have been a horribly rough ride. Once the train stopped in the e-brakes and could not be moved, a guest in the last car remarked “that was one rough ride.”

Understatement of the decade.

The Grizzly (1982-2015) has not yet run as long as its predecessor, the Wildcat (1927-1971) but like the Wildcat maintains an impressive rung on the popularity ladder. In fact, Great America park in California built almost the identical ride in 1986, also calling it The Grizzly. It just goes to show that the classics never wear out.

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