While it did have promise, it's unfortunately one contrived plotpoint after another.
For starters, while I can buy Rebecca making Baloo getting a check up to keep him healthy, I cannot believe how she literally did not question a report saying Baloo's ticker or Googleschlocker in this case was on borrowed time. First off, is that a term you can even describe the heart as? Secondly, Baloo just came in moments earlier saying he received a good bill of health, so why would she not find it odd they now said he had a bad heart?
Yes, I know one more test was supposed to come in, but have you ever heard of a doctor's report saying you had a clean bill of health and then say you're dying not even 24 hours later? Very unlikely.
Thirdly, the episode decides to do a stupid gag of Baloo thinking Rebecca is the one dying instead. Yes, I know she said she was going to die, but the fact Baloo didn't even ask her about it when she was upfront about his earlier was just stupid. That and the fact Wildcat was the one who told him should have made Baloo wonder if Wildcat was possibly mistaken. I mean, he isn't exactly the sharpest knife in the drawer.
Fourthly, the whole plot with Howard Huge. While it was kinda interesting wanting to see him make the world's biggest plane take off, he was just a nutty character who wasn't that interesting. Plus, near the climax when they escape, his guards were nowhere to be found when trying to distract him away from the SeaDuck. Seriously, that's just lazy writing. At least show them knocking the guards out first.
Lastly, the cliamx, and boy does it suck. While the concept of using reverse polarity to escape a magnet is a clever one, the episode doesn't even show how they got back safe and sound. That's just pathetic. It's like they thought, "Eh, we don't have enough time, so we'll just show them back at home without any
Seriously, this episode was just awful. It wouldn't have happened had not one, not two, but THREE contrived moments all came together. Which is why I'm giving it a 4.5 out of 10, and the only reason it's not lower is because the idea of Baloo flying into uncharted territory, as well as Howard Huge's concept aircraft was a bit of an interesting plotpoint. I just wish it hadn't come under such forced circumstances.
For a show this good, I'm really surprised the writers wrote such a stinker. You're better than this.