Sky marks: why a driver pops straight up

What the scuff on the crown records

The white mark sits on the paint, not on the grooves, and that is most of the diagnosis. The ball met the top edge of the face, climbed over it and pressed into the crown behind. Zephyr Melton got it in one line from his GOLFTEC coach: pop-ups only happen when you have a negative angle of attack. The head was still going down when it arrived.

Read where the mark sits before you rub it out. A scuff starting at the top edge and running a centimetre back says the head was barely underneath. One further back on the crown says it passed well beneath the ball, which had further to climb before it touched paint. Heel or toe side records the sideways half of the miss.

What the mark cannot give you is a number. Nobody has published a calibration from scuff position to degrees, and crowns curve differently, so read it as a direction rather than a measurement. Pebble Swing reads joint angles and the backswing-to-downswing tempo ratio out of your frames; it cannot see where on the head the ball landed.

Why the turf protects you and the tee does not

The delivery that skies a driver is often a perfectly good iron swing, and the ground is the reason. A ball on grass has its middle less than an inch up, and the sole cannot travel below the turf, so however steeply the head arrives it finds the face. The floor does the work.

On a tee that floor is gone. The ball's middle now sits level with the top edge or above it, with open air underneath for a descending head to move through. Nothing in the swing changed between the two shots. The target moved up into a place where the club can miss it low.

TrackMan states the rule per club rather than per golfer: shots played off the ground want a negative attack angle, and the driver wants the opposite. That is why one delivery earns two verdicts on consecutive shots. The attack angle guide holds the numbers themselves.

Tee height and ball position, the two cheap levers

About 1.5 inchesDriver tee height, GOLF's Top 100 Teachers

Tee height needs no lesson and no purchase. GOLF's Top 100 Teachers put the driver at about an inch and a half, with the checkpoint that half the ball peeks above the crown once the club is soled behind it. A three-wood wants roughly half an inch, an iron about a quarter.

Their reasoning runs opposite to the folk fix. The higher you peg it, they write, the shallower your swing becomes, because you are forced to hit up to reach the ball. Height is not only where the ball sits; it is an instruction to the delivery, and pegging down issues the reverse.

Ball position is the second free lever. The GOLFTEC repair Melton describes moves the ball a touch forward and adds side bend away from the target, the reverse K, so the head is past the bottom of its arc by the time it arrives. Where the ball belongs club by club has its own guide. Here it buys the head time to start climbing.

The case against teeing it lower

12 yardsCarry the highest tee gained over the lowest, per drive

Eric Alpenfels and Bob Christian measured this for GOLF Magazine in 2006. Nine golfers in each of three handicap bands, aged 25 to 71, hit off three heights: the whole ball below the crown, half of it above, and the whole ball clear of the top edge. The highest setting, the one golfers are warned about, carried furthest: 12 yards a drive more than the lowest.

The 20-plus handicap group moved most, from 160.85 yards of carry off the low tee to 178.24 off the high one, launch angle climbing from 11.23 to 14.75 degrees. It measured carry, launch, spin and ball speed, and did not count pop-ups, so it settles the distance question and leaves this one where it was.

That is the shape of the trade. Pegging down shrinks the gap between the ball's middle and the top edge, so the same steep head finds the face and the marks stop appearing. The delivery that produced them is untouched. You bought a clean crown with launch angle.

High on the face is where you were aiming

238 vs 259 yardsAdam Young's modelled carry at 4,000 rpm and at 2,000 rpm

A driver wants to be struck above centre. Its centre of mass sits behind the face, so contact above that point turns the head in a way that takes spin off the ball, which Adam Young calls vertical gearing. Chris Brook, a TrackMan-certified coach, puts it the other way round: high-face strikes reduce spin, low-face strikes add it.

Young prices the height. He describes turning a 3,000 rpm drive into 2,000 or less by striking higher, and models it: 150 mph of ball speed at 8 degrees of launch and 4,000 rpm carries 238 yards, at 16 degrees and 2,000 rpm, 259. A sky mark is that pursuit overrunning the top edge, which makes it a closer miss than it feels.