The robot test that redraws the rules on fairway woods, hybrids and irons

There's a swing tip that's been handed down through generations of golf instruction: sweep your woods. Don't take a divot, don't hit down, just let the club work through impact on a shallow arc and trust the loft to do the work.

It sounds reasonable. It's also, according to data from recent robot testing with Golf Laboratories, more nuanced than that—and for most of the clubs in this test, getting a little steeper is worth the experiment.

More than any other spot in the bag, the gap between your driver and longest iron remains a mystery. Most golfers patch it with whatever club came in the set, or take a recommendation on faith and move on. Few actually know what those clubs are doing at impact—how the ball is launching, how much it's spinning, whether the attack angle they've grooved over years of practice is helping or quietly working against them.

For this test, we ran Ping's most recent fairway woods (G440), hybrids (G440), utility iron (iDi) and long iron (G440) on the swing robot at two different swing speeds (85 and 95 mph) and attack angles (neutral and negative three degrees) to determine how much head delivery at impact affects launch, spin and carry.

Fairway woods

The most dramatic finding belongs to the higher-lofted fairway woods. The 9-wood spun at 6,300 rpm with a neutral attack angle—a spin rate that sounds reasonable for a club designed to launch it high and stop on a dime. Move to a descending blow, and the rate drops to 5,835 rpm, with carry jumping nearly seven yards at 95 mph and four yards at 85 mph. These numbers establish a baseline for fairway woods. When you hit down on the ball with a high-lofted fairway wood, spin drops and distance increases.

The 5-wood tells a similar story: nearly 700 rpm of spin lost at 95 mph, and almost five yards of carry gained. Less spin on a club already launching high means the ball stops climbing early and carries farther instead of peaking. Again, the physics make sense.

What's interesting is the 7-wood only saw modest carry gains of roughly two yards at both speeds, with spin dropping meaningfully at 85 mph but holding relatively flat at 95 mph. It benefits from the steeper angle, just less dramatically than the 9-wood or 5-wood.

The 3-wood is the outlier, and it's an important one. Unlike its higher-lofted stablemates, the 3-wood actually lost carry with a steeper attack angle—down two yards at 95 mph and five yards at 85 mph. At 15 degrees, the club is already running lower spin numbers (3,928 rpm at 95 mph neutral) and a flatter, more efficient ball flight. There's simply less high spin to correct. Forcing a descending blow here drops the launch angle without a proportional spin benefit, and carry suffers for it. The sweep-it advice, it turns out, is actually right for the 3-wood.

Hybrids

The hybrids split interestingly. The 5-hybrid gained nearly six yards of carry at 95 mph with a steeper AoA, with spin dropping over 400 rpm—a meaningful response that mirrors what the higher-lofted fairway woods showed. The 3-hybrid was much less affected: a marginal carry gain at 95 mph but a slight loss at 85 mph. Both hybrids in this test were delivered with a slightly positive attack angle, the robot naturally sweeping through impact, which reflects how most players approach these clubs. Getting steeper helped the higher-lofted one more, which makes intuitive sense given where its spin numbers started.

Long irons

At the iron end, the story shifts again. The iDi 3 utility was largely indifferent to attack angle—barely a yard of carry gain at 95 mph and a slight loss at 85 mph, even as spin dropped notably at slower speeds. The G440 4-iron, a game-improvement design built for players who want forgiveness and don't mind playing a larger profile, was actually the biggest carry beneficiary at 85 mph: plus 5.6 yards with a steeper blow. That's a meaningful number for a mid-speed player, driven by spin dropping over 400 rpm without a crippling loss of launch angle. For slower swingers carrying a game-improvement iron, a slightly more descending strike is worth pursuing.

The practical framework this data builds is more nuanced than a single swing tip. The 3-wood wants to be swept. The 5- and 9-woods—and to a lesser extent the 7-wood—reward a descending blow. The 5-hybrid benefits from getting steeper. The G440 4-iron at moderate speeds does too. The utility iron is mostly neutral.

Insights

3-wood recommendation: Sweep it at both speeds. The 3-wood already runs with efficient spin and a flat trajectory. Steepening costs carry at 95 mph (-1.9 yards) and 85 mph (-5 yards) with no meaningful benefit.

5-wood recommendation: Go negative at both speeds. Spin is running high at neutral (5,703 rpm at 95 mph), and a steeper AoA brings meaningful carry gains—4.7 yards at 95 mph and 3.9 yards at 85 mph.

7-wood recommendations: Lean negative at both speeds. Gains are modest (1.3 yards at 95 mph, 1.6 yards at 85 mph) but consistent, and total distance improves more noticeably—worth the slightly steeper approach.

9-wood recommendation: Going negative at both speeds reduces spin for noticeable distance gains. The biggest carry gains in the entire test were 6.7 yards at 95 mph and 4.1 yards at 85 mph.

3-hybrid recommendations: Steeper costs 2.6 yards of carry with minimal spin benefit. At 95 mph, the gain is marginal (1.2 yards). Club performs well with a natural sweeping motion at both speeds.

5-hybrid recommendations: Spin is high at neutral (5,755 rpm at 95 mph), and a steeper AoA brings real carry gains: 5.9 yards at 95 mph, 2.2 yards at 85 mph, with better total distance across the board.

3 utility iron: Stay neutral at both speeds. Carry gains are negligible (+1.8y at 95 mph) and disappear entirely at 85 mph (-0.7y). The utility iron delivers its best results — controlled flight, predictable carry — with a near-neutral attack angle.

4-iron: Going negative at both speeds, especially at 85 mph, leads to more distance. The biggest surprise in the test: an extra 5.6 yards of carry at 85 mph with a steeper AoA. Slower swingers in particular will benefit from a more descending blow with this club.