How much fuel did this Boeing 787-9 have on board for this flying display? Once I saw how an Airbus A350 did a validation flight prior to an airshow and flew back to Toulouse from London Farnborough without landing/refuelling (distance: 550.57 mi (886.06 km)).
I thought that these aircraft must be very light to perform at airshows.
I then saw a video of the All Nippon Airways B787 at the Farnborough Air show 2016.
How much fuel did it carry to perform such a steep climb?
Looks like he is zooming after taking off: gain as much horizontal speed as he can, then pull up very steeply to convert some of the kinetic energy into potential energy. He only spends about 4-5 seconds at the crazy steep angle.

For zooming at these speeds, the mass is not very relevant: it appears in both kinetic and potential energy terms and cancels out.

$$\frac{1}{2}\cdot m \cdot \Delta V^2 = m \cdot g \cdot \Delta h \Rightarrow \Delta h = \frac{\Delta V^2}{2 \cdot g} $$

He just needs to take a longer take-off run at higher take-off weight to reach the same speed.