Something doesn't add up. From the specs in automobile mode, fuel consumption is 7.5 l per 100 km, and the range is 500 km.
From that, we can deduce that it has a 37.5 l fuel capacity.
Now let's look at the specs for plane mode. It says that it has a range of 700 km, and consumes 15 l per hour. At 15 l per hour, it would take 2.5 hours to go through 37.5 l, but to go 700 km in 2.5 hours takes an average speed of 280 km/hour. The specs say that the top speed is 200 km/hour, so what is going on? (They do say "and more" for the top speed, but I would not expect the listed speed to that far under the real top speed).
From that, we can deduce that it has a 37.5 l fuel capacity.
Now let's look at the specs for plane mode. It says that it has a range of 700 km, and consumes 15 l per hour. At 15 l per hour, it would take 2.5 hours to go through 37.5 l, but to go 700 km in 2.5 hours takes an average speed of 280 km/hour. The specs say that the top speed is 200 km/hour, so what is going on? (They do say "and more" for the top speed, but I would not expect the listed speed to that far under the real top speed).