KC-10 Driver ✈️ 👨‍✈️ B-737 Wrangler @MCCCANM
This is called a “bounce” or a “bounced landing”

They aren’t particularly dangerous initially, but they can be when pilots try to continue the landing after the first bounce…the most common advice is to go-around & try again, which these pilots did

The definition of a “hard landing” varies some by aircraft, but a touchdown at a rate exceeding 600 feet per minute is a number that’s common. Near that vertical velocity, the effect will likely be jarring for passengers. It may even knock some interior panels down or cause some O2 masks to drop, but airframe damage is usually minimal to none – the airplane requires a specific inspection, then is released back to operations, usually without much delay

Bounces don’t always mean a hard landing, and vice versa, but they share some similarities; slow airspeed is one factor. Some airplanes handle a little better in a bounce than others, but if the bounce continues, most airplanes will end up damaged – either by striking the tail on the concrete (pulling on the yoke, trying to slow the rate of descent after the first bounce), or by eventually touching down with the nose wheel first, which it’s not designed for…watch how fast that nosewheel comes down after the first bounce. Now imagine bouncing again, with a magnified effect

In part it’s because as the aircraft is bouncing, it’s also losing airspeed – which means control effectiveness decreases. You may either end up with the yoke in your lap or the nose pointed at the ground. Neither is good!

This is also the reason that the first 3,000’ of large runways are significantly thicker/deeper than the rest of the runway; this is the landing zone & the concrete has to be stressed for higher forces than is required if you’re just taxiing around

Though spoilers (panels on the wing that pop up after landing, “spoiling” lift & slowing the plane) deploy once the main gear touchdown, pilots retain the ability to go-around up until the point the thrust reversers are deployed. Advancing the thrust levers for a go-around will – in some airplanes – retract the spoilers (I can’t tell if the spoilers tried to extend here or not…I’m not very familiar with/747 systems & sometimes the spoilers have multiple uses)

In any event, they had a bounce & did the right thing. The airplane probably has minimal or no damage, the runway is fine & it will be back to business as usual quickly