We don't the timeframe of dragons wing flap, by assuming the time from between 1-5 sec , we can get :-
1- 1000 miles per second ≈ 1000 * 1609.34 ≈ 1,609,340 meters per second
2- 500 miles per second ≈ 500 * 1609.34 ≈ 804,670 meters per second
3- 333.33 miles per second ≈ 535,774.2 meters per second
4- 250 miles per second ≈ 402,335 meters per second
5- 200 miles per second ≈ 321,868 meters per second
So, the dragon's speeds would range from approximately 321,868 m/s to 1,609,340 m/s,
ranges from High Hypersonic+ to massively hypersonic+ tho it really depends on the timeframe of dragons wing flap