In the continuing tug-of-war between rulesmakers and golf equipment manufacturers, the U.S. Golf Association has informed equipment makers it is studying three “research areas” that potentially could result in rules changes.
The three areas are spin generation, clubhead moment of inertia, and the adjustability of woods and irons.
In a letter to manufacturers dated March 30, the USGA said no rules changes are being proposed at this time and that any future changes would occur only after the USGA’s normal notice-and-comment process in which opinions are solicited from golf companies, associations and individuals.
Of the three research areas identified by the USGA, moment of inertia clearly was the hot topic among industry insiders who arrived early at Augusta National Golf Club for the Masters.
Moment of inertia, which defines the clubhead’s resistance to rotation on off-center hits, never has been limited by the rules of golf. As the size of driver heads has expanded dramatically in the past 15 years, clubhead resistance to twisting has experienced a corresponding increase. This has resulted in a modern generation of drivers significantly more forgiving than those of the past.
In 1990, the average volume of a metal driver head was about 165 cubic centimeters. Many of today’s drivers measure 460cc, the size limit established by the USGA in 2003.
“We are undecided what it means,” said Larry Dorman, Callaway’s senior vice president of global press and public relations. “We don’t know where they are going with moment of inertia, but average golfers are the ones who have really benefitted from this.
“I have given up trying to define the intentions of the USGA. It doesn’t seem to make any sense to legislate against ordinary golfers when we’re trying to grow the game.”
The research areas of MOI and spin focus mostly on woods and not irons. Drivers and driving distance remain primary concerns of the USGA (and also the Royal & Ancient Golf Club of St. Andrews, Scotland, which is listed as a partner in this research initiative).
Nike Golf executives, riding high on the prominence of Tiger Woods and his Ignite 460 driver, declined to discuss USGA driver research. But Tom Stites, Nike’s director of product creation, did talk briefly about another new area of USGA research – testing irons for spring-like effect with the possible objective of eliminating “hot” irons.
“It’s not important,” Stites said. “We shouldn’t forget the arms race of the late ’80s and early ’90s. The lofts (on irons) were jacked up (strengthened) so much that golfers were getting unrealistic distances.
“Any time you do this, you have to make (distance) compensations somewhere else. If your pitching wedge goes 150 yards, it’s not a pitching wedge. It doesn’t make sense,” he said. “The only clubs in the bag that you don’t hit a specific distance are the driver and 3-wood. What you want in irons is consistency. We have worked very hard to design irons that go the same distance every time.”
The USGA correspondence clearly outlines the research steps it is taking and possible outcomes. Highlights of what the governing body is doing in each category include:
Spin generation: According to the USGA, one of the key performance parameters controlling ball flight and ball response on the ground is spin. The USGA has been investigating how spin is generated when a golf ball is struck by a golf club – using computer simulation modeling, lab testing, robot testing and player testing.
This could lead to future proposals for new measurements, new tests and limits for club or ball parameters that affect spin.
Clubhead moment of inertia: The USGA is concerned that any further increase in this measurement may reduce the challenge of the game. Though the governing body indicates that the current restriction in head size could serve as an “effective cap” on further increases, it is concerned that the emergence of new clubhead construction materials – with greater strength and lower weight – could enhance moment of inertia. The USGA’s goal is to determine whether a limit on moment of inertia should be established.
Adjustability of woods and irons: The game’s rules currently state that woods and irons must not be designed to be adjustable – except for weight. The USGA is considering expanding the types of adjustable features permitted for woods and irons. This could lead to a new proposal, but any rule change would still prohibit the making of adjustments during a stipulated round.