Golfers have access to more data about their swings than ever before. Now it’s time to learn what it actually means

By Mike Stachura
To say the launch monitor has become ubiquitous and vital in golf is like saying Google is a useful tool on the internet. Not only is it likely that you will find player after player on golf’s elite professional tours staring at the launch numbers churned out from a GCQuad or Trackman 4, golf equipment retail’s most important asset today is the magic box that tells both fitters and customers alike that yes, this is the best club you’ve hit today. No other consumer product on the planet—not dishwashers or minivans, not pizza stones or sports bras, not table saws or OLED TVs—has a device that can define unequivocally this product is better than that one but more importantly this product is that much better than the one you currently own.

Of course, the launch monitor’s worth is just as important to gauge how well you’re swinging the club, too. The launch monitor isn’t just a selling tool these days, it’s a teaching tool. And in your hands, which is increasingly possible with affordable devices like the Rapsodo MLM and the FlightScope Mevo and home simulators like the SkyTrak, launch monitors are how you learn to improve and make sure those tips from your pro are sticking. (With the new Golf Digest Schools Connect+, you can share your swing using the Rapsodo MLM with a Golf Digest-ranked teacher in 1-on-1 virtual lessons.)

The launch monitor is the foundation of understanding performance because its information is so specific. It means those small numbers signal big improvements. As Golf Digest Top 50 teacher Martin Hall said about the GCQuad launch monitor he uses in teaching, “One of the things I really enjoy is that it puts every decision I make as a teacher on trial: Did I do something that’s moving you in the right direction, or didn’t I?”

Of course, in that instance when you might be alone in a simulator and those launch monitor numbers are flashing across a screen like the code sequence in The Matrix, you need a way to separate the noise from the substance and take advantage of the technology.

One warning: The best way to read performance numbers coming from a launch monitor is to focus on a reasonable average, not the one perfect shot. The best driver isn’t the one that hit that home run shot with perfect numbers, it’s the one that produces the most consistent numbers, the best average distance with tight dispersion. You improve your golf game with reliable averages, not hoping for miracles. Save that for your dating app. That said, there’s also a lot you can learn from that perfect swing. Archiving it, which is increasingly possible with launch monitor apps, lets you go back and figure out how to make those miracles commonplace.

OK, there are basically two kinds of launch monitors, both of which use ultra-sophisticated algorithms to further interpret ball flight. In short, launch monitor technology knows what your club and ball are doing in a way the human eye never ever could, but that knowledge is truly game-changing.

There are literally dozens of data points on display, but a select few stand out as ones you should understand. Let’s look at what some of those key metrics are and how they should be used so the next time someone extolls your ball speed or smash factor, you actually know what they’re saying.

Carry/Total distance: You know what these are: how far the ball flies through the air and how far away from you the ball is when it stops bouncing and rolling. Total distance should be your focus on evaluating drivers; carry distance is most important in irons. (If the guy behind the launch monitor is talking about total distance when you’re evaluating irons, immediately leave the area because this person is not helping you.) Since all launch monitors tend to have their own ways of calculating bounce and roll, sometimes total distance can be overstated. What you might want to do is pay attention to one of the obscure numbers on the launch monitor called landing angle. To optimize total distance with the driver in most conditions, you’ll want a landing angle in the high 30s. For example, Titleist recommends that a landing angle for the driver around 37 degrees is pretty good and below 30 degrees is never a good fit, while a middle of the road 7-iron’s landing angle is between 45 and 55 degrees. Finally, if you’ve never been fit before or don’t otherwise keep track of your distances with a GPS app like Arccos, don’t be surprised that the distances you’re seeing are less than you think. According to average golfer data accumulated by Arccos, the stat-tracking platform that uses grip-based GPS sensors, the average driving distance for a male 11- to 15-handicapper is 219 yards. Even worse, Arccos reports that the average 10-handicapper expects his 7-iron to go 165 yards when in truth it only goes 148. A launch monitor speaks the truth, even when that truth is hard to take. Take it and learn from it.

Ball speed: This number, expressed in miles per hour, is the velocity of the ball leaving the clubface. The higher the ball speed, generally, the more solidly you’ve made contact (but more on that later) and the farther your shots will fly. For perspective, the average ball speed with the driver on the PGA Tour is about 170 miles per hour, and on the LPGA Tour it’s around 140. For a 7-iron, it would be 25-30 percent less. Ball speed tends to be king of the launch monitor numbers, but it isn’t everything. For example, you could be generating somewhat more ball speed with one 7-iron vs. another. But some of that difference could be the result of a difference in loft. Stronger lofts, generally, provide a more direct energy transfer for faster ball speeds. That’s why, particularly for irons, you have to look at more than ball speed.

Launch angle: This number, measured as an angle up from the ground, reflects the initial trajectory of the ball. It is different than the loft of your club for a lot of reasons, and can have a lot to do with another number we discuss below, Angle of Attack. For the driver, average golfers really want to get this number safely into double digits (12 degrees is a good starting place). Only the highest swing speed golfers can get away with a launch angle as low as 10 to get decent distance. But even for them, higher will yield more distance. For perspective, a couple of extra degrees of launch angle might mean five extra yards of carry on an average golfer’s tee ball.

Spin rate: Every shot has backspin, even a putt. Most launch monitors see both the amount of backspin, in revolutions per minute (rpm) and the way that the axis of spin rotation is tilted, what some folks incorrectly call sidespin. (Technically, if a ball had sidespin it wouldn’t get off the ground.) Combining relatively higher launch with relatively less spin is generally a recipe for distance with any club, although with irons the less spin you have the more your shots will roll out on the green. Again, be careful about focusing on getting lower and lower spin numbers, especially if you’re not generating a lot of clubhead speed. A very low spin number off the driver on a centre hit is fine, but if you mis-hit that same shot a little high on the face, you might not have enough spin to keep the ball in the air. As well, if your swing speed is below 95 miles per hour, a few hundred rpm’s of spin won’t mean as much to your best distance as getting the launch angle up in the right place. A high launch angle gives you more margin for error than an ultra-low spin number.

Angle of Attack: This refers to the upward or downward path of the clubhead as it’s travelling toward impact. The number is measured in degrees as a positive or negative number, unless your path toward impact is perfectly level (in which case your angle of attack would be zero). Generally, unless something very strange is happening or you’re hitting the turf a foot behind the ball, this number will be in the single digits. It certainly shouldn’t be the same for all clubs, and ideally, it should be a positive number for tee shots with the driver and likely a slightly negative number with iron shots. A positive attack angle with the driver is one way to help shots launch higher and with less spin (the recipe for distance). Still, you can have a positive attack angle with the driver and it may not indicate you’ve made a good swing. You can simply flip the club through impact (which actually reduces clubhead speed), rather than having them move the club on a slightly ascending path in response to a proper body turn. Short answer: If you’re maintaining or increasing your clubhead speed and your ball speed with the driver, and you have a positive angle of attack, you will see more distance. How much? A recent test from the club fitting wizards at TXG Tour Experience Golf in Canada showed the difference between a positive angle of attack and a negative angle of attack with the driver, with swing speed and ball speed as a constant might be as much as 35 yards. Conversely, of course, a positive angle of attack with your irons likely means you’re thinning or topping the ball or even missing it entirely. Instead, you want a negative angle of attack where you’re delofting the club at impact. That’s turning a 7-iron to a 6-iron or a 5-iron in terms of the loft at impact (which is technically known as “dynamic loft”). A recent Golf Digest test by Golf Laboratories swing robot showed that a tour-like angle of attack of minus-7 degrees could yield as much as 23 yards more carry for the average golfer. Of course, changing your attack angle is often the result of a swing change, an especially arduous one with the irons. A small trick to improve your angle of attack with the driver, however, is to play the ball a little more forward than your usual position, which is probably too far back anyway if your angle of attack is negative.

Smash factor: This number sounds sexy but it’s a pretty basic science and a pretty reliable indication of how solidly you’re striking the ball in the centre of the clubface. It is a simple ratio of the ball speed to the clubhead speed. For the driver, that ratio should be getting to 1.45, maybe a hair higher. If you’re not seeing a lot of variability in your smash factor, that should be an indication that you’ve got the right club and right shaft combination. Smash factor can apply to all clubs, but the ideal ratio of ball speed to clubhead speed decreases because as loft decreases the energy transfer is less direct because of the more oblique impact. According to Trackman research, a good smash factor is around 1.38 for a 6-iron and 1.19 for a pitching wedge. But again remember that if you’re comparing two irons from different companies those lofts might be different and thus the optimal smash factors will be different. A good fitter will know the difference, and of course, it never hurts to ask when you’re not sure.

Of course, now that you’ve gotten a little tutorial, maybe you’ll be asking less and learning more from your numbers. With any luck you’ll be using the same lingo as a tour pro. And if you can’t play like one, at least you’ll be able to sound like one.