Below is concept art of Scourge as an airship, from the comic Hearts of Steel. It looks pretty badass. In theory, any decent vehicle can be a good alternate mode. But realistically speaking, airship design must consider how much air they need, how much weight they can carry, and how maneuvrable they are. It'd probably need to be really big, can't carry enough metal so it'd be really light, and may have serious issues with mobility so with combat it can't work out. This link explains how realistic airships need to be: Physics ruins all our Fun: Luxury airship edition It may only be worth as a mobile base, and for any poor robot who takes on that alt mode it's as good as sitting in the air with a target on your back. So I guess not. It's a pity because there are some fantastic airship designs.
I think the best way to make an airship Transformer work would be to make the robot mode not humanoid. Like, use the balloon for wings on a bat or bird, and the internal frame for the arms. Wings are the biggest bodypart of most winged animals; you'll have a much easier time using the balloon on an avian robot mode than a humanoid one. You could try to use it as a cape or cloak or something on a humanoid but it'll certainly be ridiculously oversized. Plus I think an airship would demand a character's role to be aerial surveillance/reconnaissance to make any use of an airship mode at all, and say, an Eagle would have more to do in the sky than a humanoid form. Aside from being a spy, this TF could maybe deploy Funnel-like drones (if you're familiar with Gundam) or small parasite ships for defense or to create a stealth/forcefield grid. Tiny drones like bees guarding a flying beehive, to keep the airship lighter than air.
Why not? We had Alannah turn into a Viking boat. We've had movie-formers turn into household appliances too. Though I'd like to hope its more sturdy.
Sure. As a "fake" airship that probably flies under gravity repulsors and jet engines. Not as an actual lighter-than-air airship. But that's ok because a lot of TFs with car modes are disguised wheeled tanks, going by their tech specs and bios. They only look like cars.
Oh and it would probably need hidden thrusters so it won't hafta flee at the Speed of Snail. Could make for a good spy?
An airship would be useful for spying, but any character with that as an alt mode would definitely need something to boost their speed, especially if they were attacked by enemy jets.
I don't see why not. airships often have large metal frames to help keep their shape. the ballon could simple deflate and compress into the robot mode. If you wanna think outside the box the baloon could even become the robot mode torso give them a great big inflatable belly.
The biggest challenge is to design a compelling robot mode without too much shellforming. Naval shipformers present this challenge too, but it's going to be harder with an airship because parts of the hull can't be hidden under the waterline.
It doesn't seem to be much of a challenge to me. Considering the person in the drawing above, just took the existing Scourge design, flipped him upside down, and then attached him to a big gigantic balloon.
In this IDW comic book the blimp part of the alt mode was an actual inflatable fabric balloon. Only the control car with engines part was an actual robot. That's handwaving most of the alt mode away.
Well, I was actually assuming it was a big gigantic hologram for intemidation purposes, as well as disguise. After all, there is no need for them to have the balloon part. But, it sounds like your way works too. Not really. All you would have to do is set it in a time period when they are common.
Sure it could work. The bot could store an inflatable balloon in his backpack. The balloon could be made from some type of super strong alien-tech material requiring no internal supporting structure. It would be inflated with hot air produced by the bot. And make it a color changing balloon so it can be made black to absorb solar heat energy in daytime to make the bot more energy efficient.