Catching up with the Gravity Group

It’s been quite a long time since we last checked in with them but we were able to catch up with Mike Graham of the Gravity Group and discussed a few of their current projects, including the new Timberliner trains. Thanks to Mike and the rest of the team for taking the time to answer our questions.

What is it like working with a team of creative engineers? What has your typical role been at the Gravity Group?

It’s been great working with our team over the years.  We thrive on doing things that are unique and challenging.  We don’t really have typical roles as we all wear the many hats required to design roller coasters and run a small business.  That being said, however, in the last few years I’ve been the lead engineer on the Timberliner project.

Speaking of the Timberliners, how was your first ride in the new trains on the Voyage? Did it ride like you expected it to?

The first ride on the Timberliners on the Voyage was very rewarding.  It was great to share the experience with William Koch III as well as the Koch and Holiday World family.  The ride itself was quite different while still being the same Voyage.  Through the twists and turns, in particular, the train glided effortlessly.  For the most part, it did ride like I expected it to, and riding it also helped to identify additional aspects of the car that we want to tweak.


What were some of the challenges in designing the Timberliners? Why were they delayed a year on the Voyage?

With any new product that did things so differently on so many fronts, there were unknowns that could only be identified through extensive testing.  The majority of the delay was due to motion in the seat area, which it turns out is a combination of many different factors.  Getting to ride it is the biggest hurdle on the project, and we will continue testing in early spring.

The Twister at Grona Lund appears to have a very tight turning radius. How are the Timberliners able to negotiate these uniquely small turns?

The Timberliner front car chassis is a dual-purpose design.  The first purpose is to provide the necessary “tractor” car on the trailer car design of the Timberliner.  The second is the chassis for the Splinter compact coaster design that can turn on an unbelievable six foot radius.  With some adaptation of the trailer cars, we were able to create the Twister with a very tight radius to contort into the very confined area at the park.  With the industry-exclusive steering mechanism on the cars, these trains can do what no other train can.


We’ve heard there is a wooden coaster first on the new Twister coaster (something regarding the handrails)? What makes it unique and what was the reasoning behind implementing it on this ride?

The park wanted a classic wooden coaster feel, and we went with a special bright white coating on the structure along with an industry first of a brilliant red plastic structural lumber for the handrails.  This will give the handrails a long-lasting historic red look while retaining their structural integrity.  We are excited to reveal another classic coaster detail soon.

We can’t wait to hear what that next detail is! How did you come up with the idea for the “high five” element on the new racing/dueling coaster in China?

For many years we have brainstormed about banking at 90 degrees at the top of a hill.  Combining that with the thrill and interaction of a racing coaster, the “high five” was a feature which Chad had concocted for a ride on a different continent.  It just seemed to be a perfect fit for this ride in Wuhan, China.


Since this is for Coaster101 I have to ask, what’s your favorite roller coaster that you’ve been on?

I do love all of our Gravity Group and Custom Coasters rides, but it’s hard not to say The Voyage might be my favorite as I have had some ridiculously awesome rides on it.  However, I am so looking forward to Twister, Wooden Warrior and the Wuhan racing / dueling coaster.

I certainly agree with you there, Voyage is still my all-time favorite coaster! I can’t wait to experience it in the new Timberliner trains.

We look forward to watching these other projects come to completion. Be sure to check out the Gravity Group’s Facebook page for the latest construction pictures. Thanks again to Mike and the Gravity Group for taking the time to talk with us and for designing such awesome coasters!

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