mattcolville
Adventurer
If you think you've got 10 hours, plan for a 4-6 hour experience. Don't do open-ended sandbox encounters, like "they wander around and have to make Con checks" or "they meet some villagers and RP". No. You've got to have a solid plan with a realistic time budget. They're on a Ride, not in a Sandbox.
I've got a couple of weeks, I don't mind doing time to give them options. I can't imaging "wander around making con checks" would be one of them.

Here's a specific adventure outline based on your ideas:
1. Intro and opening scene (30 minutes). The flying ship could be a bug. An animated bug: either undead, or via Animate Object-like spells. The players are inside the hollowed-out abdomen, bound and blindfolded with hair rope.
When they crash, they've got three ready-made goals: 1) survive, 2) find out who attacked them*, 3) get revenge on whoever imprisoned them. Those are Big Esoteric Goals. Give them an immediate goal by placing some obvious destination in the near distance, and a threat to get them there. Like a ziggurat on the horizon, and a giant sandstorm bearing down on them. They know they need to get to the ziggurat to have any chance at survival.
Note: from here until the Ziggurat, do not let the players drink any water. Place a giant glass pitcher of ice water on the table, but do not let them drink it. Turn up all the lights, too. Go buy one of those cheap floor lamps to really sell the sun. Trust me on this. Your players will talk about your commitment to the bit for years to come.
I think a giant flying insect is perfect. I wanted to capture some of that Fury Road feel so I felt like giving them a desert skiff, like a ship of the desert that was attached (as a kind of life boat or just a supplemental vehicle) to the flying bug would be cool.
Still have that big ziggurat in the distance, that's a great idea, but give the feeling like it would be impossible to get to on foot.
Plus the ship speeding across the desert might mean other ships coming after them. I want a swashbuckling ship-to-ship encounter a la Fury Road.
2. Assess, repair, first chase (1 hour) After the crash, the giant bug's in bad shape. The wings are completely wrecked. But it can still crawl. Give players the means to patch it up, while interrogating their prisoner (he's crippled, but alive, and bargains well for his life). Then chase the characters to the ziggurat. Elves in Dark Sun are essentially the bikers from Fury Road (they run fast). Put some on kank-drawn chariots. You've now replicated the Buzzard tribe encounter from the first chase scene in Fury Road.
Man that's awesome! Great idea!
3. Betrayal, into the sandstorm (45 minutes) After the PCs deal with the elves, their prisoner somehow alerts his superiors. Now a new Templar-led force is on the way. More chariots. More scuttling up-armored animated bugs. On-again, off-again combat as forward elements catch up to the bug and try to slow it down. Crazy environmental dangers as the sandstorm nears. Keep moving toward the shelter of the ziggurat, which they reach just as the sandstorm engulfs them, sweeping away nearby pursuers and driving them into its unknown depths.
Yeah I definitely want the PCs to think the Templars are after them. I think this coming from a trusted NPC who betrays them might be effective. Especially if he's helped them survive up until now, classic.
How about they discover a huge reservoir within the ziggurat, a huge columnar pool taking up the entire middle of the ziggurat, and this asset (coupled with the threat of the Templar army) leads to a segment where they shore up defenses. Montage-style as they jury-rig traps and prepare hard points and fallback positions for a siege. Give them a map and some resources and let the players collaborate and go nuts. All the while, tease out story elements.
I love the idea that the Ziggurat is not a dungeon, per se (I mean, maybe there are some defenders) but that there's some great secret hidden within that galvanizes the players and makes them think it's worth fighting over.
These are great ideas and very inspiring, I think this is going to be a huge success. Thanks for helping!