Ah... no. I was a flier. I did all of this myself, but... er, here. [He'll just let the screen split in two to display an image similar to this, which reveals that if anything, besides a slightly drastic redesign, Jetfire added mass to his frame. Quite a bit of it.]

I've been upgrading and modifying my frame for my function and effectivity for a long while now.

[He shrugs, and then his optics narrow a little as he thinks back on that.]

Ours by association. A... super-powered clone finally had its systems overwhelmed by the solar fusion generator it was powered by, and was going to explode. I was on my way of stopping him when I... and Starscream, got pulled elsewhere.

[A simplified explanation, but it's the easier one than bringing up apparent powering-up by an apparent strange form of energon (perhaps), and all the little bits implying something a lot less straight-forward.]