Hi, my name is Jeff Bryant. I live in Northern California and am a second generation land speed racer. My father started coming to Bonneville in 1957 (Tom Bryant). I have been coming since the mid ‘60’s.
I have been a private pilot since 1991. I hold (have held) 200 mph records at Bonneville, El Mirage, and Muroc. On the way to the Bonneville 200 mph record I drove our D Competition Coupe. I crashed it at over 200 mph. Fortunately, I was only bruised in the ordeal. We made many changes over the years and learned about concepts called “Weight and Balance” and “Center of Pressure”. These are physical truths that apply to landspeed racing and flying (Private pilots are required to know their “numbers” related to centers of pressure and balance). If you don’t pay attention to them, you can load your plane in such a way that you can take off but not safely land. This information is a matter of life and death and not theory.
Over the years we have found that these physical “truths” apply to landspeed racing in the same “life and death” way they do with private pilots and their planes. This became painfully clear when we lost my youngest brother, Barry, in August of 2009 at Bonneville.
Since that day, my “therapy” has been to immerse myself into safety at Bonneville. I have been a tech inspector for several years now and am reaching out through this forum to tell other racers about the important calculations called “weight and balance” and “center of pressure”.
This information is not official and SCTA does not require that racing teams include this information in the design and modification of their vehicles. But I believe it is imperative that we know about these things. Here’s why:
Every landracing team should assume that someday their vehicle might leave the ground. Denial of this possibility puts your life at risk. A properly configured vehicle will keep its nose relatively straight when off the ground, much like a dart. That way the chute remains effective and helps stop the car. There are exceptions to this, but the odds of safely coming to a stop increase with a properly configured car. How your vehicle handles in crosswinds and the effectiveness of your steering are also affected by these calculations.
So, if you are building a new vehicle, have a vehicle that progressively gets harder to handle the faster you go, have a vehicle that seems to spin easily, and especially if you plan to exceed 200 mph, you should know about and apply this information. KNOW YOUR NUMBERS. We can discuss your question here or I can be reached at jbryant200@hotmail.com.
P.S. We knew our numbers on our competition coupe and still got in trouble because we did not RECALCULATE after making modifications to the car. Don’t you make the same mistake. Always recalculate whenever you change the weight distribution or shape of the vehicle. You always want the center of gravity to be four to six inches in front of your center of pressure.
I’ve heard many in landspeed racing say they have trouble with traction and handling. The common thought is to add weight to the rear of the vehicle when tires spin. This can be seriously dangerous in some cases. ALWAYS make changes to your vehicle with the proper configuration of "The Numbers" in mind.