Here is the scene where the Flying Fortress was going down towards Nebel Plateau, as Volcanion refills more water, then the heroes escape and Volcanion sacrifice itself to destroy the flying forrtress goes in Team Robot In Pokemon Movie: Volcanion and the Mechanical Marvel.
(Suddenly an Strange Rumbling appears, The Flying Fortress began to crumble)
Takato Matsuki: What's that noise?!
(Raleigh checks the control system)
Emerl: Prince Raleigh, what's going on?
Raleigh: Oh, no! The fortress is set to fall onto Nebel Plateau!
(Everyone gasp in horror)
Thomas: Bust my buffers!
Muscle Man: Oh, no, bro!
Regirock: Our home!
Regice: What do we do now?
Tai Kamiya: Can you stop it?
Raleigh: It can't, it looks like the control system is out!
Kimia: All because of Alva. And even if we we're be able to escape.
(The prediction starts with all the Nebel Plateau Pokémon watches the flying fortress going down and then crashes to Nebel Plateau and then becomes a massive explosion as the prediction ends)
Clemont: Isn't there anyway at all?
Louie: Is it?!
Camillot: How do we stop it?!
Raleigh: We can't change course.
Kuffs: Then how do we stop it?
Raleigh: The only way would be to explode the fortress into a pile of dust.
Gobbol: How are we gonna do that?
Volcanion: Explosions are my specialty!
Ash Ketchum: Hold on, you're out of water.
Kenta Kitagawa: How are we going to find water in this fortress?
Raleigh: Part of the fortress runs on steam, so it has water tanks. Volcanion, I'll take you there.
Volcanion: Please do.
Raleigh: Everybody, wait on my sister's flying machine.
Ash Ketchum: I'm going with you!
Takato Matsuki: (Gives a sleeping Jeri to Sonic) Sonic, take care of Jeri, please.
Sonic: Okay, Takato.
(As the flying fortress continues to go down, we go to the heroes made it to the water tanks)
Raleigh: Over here!
Volcanion: I can smell water!
(Ash, Raleigh and Takato tries to move the wheel, but it's stuck on tight)
Raleigh: This thing's really stuck!
Takato Matsuki: We need a plan!
Ash Ketchum: I've got it! Go for it, Pikachu, iron tail!
(Pikachu jumps and uses Iron Tail on the old wheel and it moves)
Takato Matsuki: It worked!
Ash Ketchum: Kay, thanks!
(They move the wheel as hard as they can)
Ash Ketchum: It's moving!
(The water comes out)
(Volcanion jumps and absorb all the water)
Raleigh: Excuse me, you said you're name is Ash and you're name is Takato, right?
Ash Ketchum: That's right?
Takato Matsuki: That's me.
Raleigh: I've been acting like such a fool. Spending so long, shutting myself up in my lab. That's why, Alva and his friends had such an easy way tricking me that way.
Takato Matsuki: Don't worry about the truth for Alva and the villains, cause your Kimia's brother.
Ash Ketchum: Know what I think? You should head out on you're own journey with a Pokémon.
Takato Matsuki: He's right, you should learn everything about the world of Pokémon, instead of learning anything what you did in the past with the bad guys. That would be awesome.
(Raleigh smiles, then suddenly part of the fortress collapse and crashes on the forest. Then Volcanion's circle and lines turns red to blue finally full of water, then they run to the center of the fortress)
Ash Ketchum: Volcanion?
Volcanion: Say, perhaps I should create an explosion right here.
Takato Matsuki: You think you might be able to destroy it?
Raleigh: Beneath the center of the fortress. So I do think it would be effective, but...
Ash Ketchum: Then you won't be able to escape.
Raleigh: Yeah, that's the truth.
Takato Matsuki: We really don't want you to die.
Ash Ketchum: You said you're power enough to level up a mountain, right? So why not follow the plan and blown up from outside?
Volcanion: Agreed. We should all go back together.
Ash Ketchum: Yeah!
Raleigh: Let's hurry!
Takato Matsuki: Right!
(Later our heroes are on Kimia's flying aircraft and then Volcanion along with Ash, Pikachu, Takato & Raleigh shows up)
Raikou: So as Ash, Pikachu and Takato!
Guilmon: You're back, Takato.
Ash Ketchum: Kay, Volcanion, go get 'em!
(Volcanion jumps off the aircraft and looks at the hole preparing to jump)
Kimia: Get on board after the blast!
Volcanion: Alright! Just go!
(Volcanion uses mist to push the aircraft away as Volcanion jumps in the hole)
Ash Ketchum: Volcanion!
Moltres: Our friend!
Kimia: No, you can't do that!
Entei: Get away from there!
Articuno: Let's hurry!
Zapdos: Look out for the falling rocks!
(Kimia avoids from the falling rocks, one of them hits the left wings as Kimia tries to keep her aircraft keep flying)
Suicune: We've got to help them! (Fires Aurora Beam on the rock)
(Three Regi Trio fires Hyper Beam on the falling rocks. Now we go to inside of the Volcanion is where it enters the center of the flying fortress
Volcanion: Well, I'm going out with a bang! Time to Blast! (Charging up Explosion) Magearna, my friends. I couldn't protect all of you... forgive me.
(Volcanion yells and lets out the attack as the Flying Fortress shines)
Emerl: What's happening?
Ash Ketchum: Volcanion.
(All of the Nebel Plateau Pokémon watches the flying fortress as it explode)
Tai Kamiya: Volcanion!
Ash Ketchum: You lie to us! You said, we all go back together!
Pikachu: Pika, pika!
Slumbo: Volcanion is dead!
Takato Matsuki: He should have learned the truth to go back!
(Now we see the Villains who escaped see the event)
Mr. Ross: (In Megatron's voice) No. no!
Dr. Drakken: They destroyed our weapon!
Shego: (Growls in anger)
Primus: (In Starscream's voice) Not to, call you a coward, Ross. But sometimes, cowards do survive.
Mr. Ross: (In Megatron's voice) This isn't over.
(Mr. Ross opens a portal to allow the villains to escape)