I had a big mistake in the comment above, it's 220 km/h or about 60 m/s. cos(28)=0.88 0.12*(2*pi*7000 km) = 5300 km 5300 km / 24 h = 220 km/h

I had a big mistake in the comment above, it's 220 km/h or about 60 m/s. cos(28)=0.88 0.12*(2*pi*7000 km) = 5300 km 5300 km / 24 h = 220 km/h 220 km/h / 3.6 m/s/km/h = 61 m/s