Shooting ariplanes in motion is not easy, I know. I've experienced this myself some 20 years ago, exposing more than 4 rolls of 36 exposure film to get a few real keepers.
Now for some C&C, if you don't mind.
Composition would be a bit better if the airplane was a bit off-center (on the right to suggest getting closer, on the left to suggest getting further away). A bit of cropping could actually make this very good shot even better. I suggest a slightly panoramic cropping on the second pic.
And I agree with NewportPreacher: a slightly slower shutter speed would've helped blur the propeller just a bit more (but then it might have been too slow to freeze the aircraft, maybe).
Overall, very nice shots.
On a sie note, I must say I LOVE this aircraft. One of my all-time favorites!
Keep posting!