Uber (UBER) showed off designs for an Air Taxi cabin, as part of a planned service to let riders make trips in the airborne vehicles.

The design was revealed at the Elevate conference in Washington, D.C., which is dedicated to putting Uber's network in the air through helicopters, Uber Eats drones, and the air taxis.

There are a lot of hurdles to getting air taxis off the ground, and Uber says it'll be at least 4 years before this concept to fruition.

But with Uber's stock slumping since its IPO, its not clear how much investors want to wait around.

Related. Uber's Ambitious Helicopter and Flying Taxi Plans Could Test Investors' Patience

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