XB-70, talked to a gentlemen who flew chase on one once, and he was still drooling, thirty years later.
AN-225, just to park next to those cheeky little A380s. OK, and because of the little globe back at the nav station.
A-4 because a test pilot that flew every jet known to mankind said that would be his first choice.
Any four engine seaplane, maybe a Sunderland
PC-6
In reality,
1. B747-200
2. PA 12 with an 0-360 bolted on
3. CV-240
4. Helio Courier
5. Citabria