"We need flying burgers," Uber boss Dara Khosrowshahi said earlier this year, revealing his company is working on a way to deliver food by drone.

Although this could be dismissed as literal pie-in-the-sky thinking, Uber clearly thinks a flying food delivery service can take off, and is on the search for staff to make it happen.

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On Sunday night, October 21, the company hastily removed a job posting looking for an operations executive who can help make the service functional as soon as 2019, then commercially available in multiple markets by 2021.

The listing, spotted by the Wall Street Journal over the weekend and quickly removed by Uber, was looking for a drone expert with the experience to "enable safe, legal, efficient and scalable flight operations."

Uber took down the advertisement and said it "does not fully reflect our program, which is still in very early days."

Creating a functional drone delivery service by 2019 is certainly an ambitious goal for Uber to set itself. Amazon has been working on drone deliveries for several years, but is only at the stage of delivering to a couple of properties in the British countryside — which are both located very close to an Amazon logistics center. The first deliveries began at this location in late-2016, but Amazon has said very little about the service since.

Although the technology exists to carry packages by drone —with burgers and other meals likely not a problem either — gaining U.S. regulatory approval will be tough. However, there are signs that regulators are open to the possibility.

The briefly-listed job post comes after the U.S. Department of Transportation approved a commercial test program for drones in May this year. The department gathered together a range of companies — including Uber — to work on delivering a viable solution. Other companies involved with the program include Apple, Microsoft, Intel, and Zipline, a blood-delivery startup from Rwanda.

Speaking in May, Uber's CEO Khosrowshahi said: "Uber can't just be about cars. It has to be about mobility. It's my personal belief that a key to solving urban mobility is flying burgers, in any city. We need flying burgers."