The US Transportation Department is to review progress on the certification of flying taxis.

The department’s Office of Inspector General noted that interest in highly automated aircraft that can be used for passengers and cargo, designed to operate in populated areas, has grown substantially of late.

However, it also said that it creates “new and complex safety challenges” for the US Federal Aviation Administration (FAA), which is currently reviewing applications for certification including electric vertical take-off (eVTOL) aircraft.

These craft use electrical propulsion to take off, hover and land vertically. The aircraft typically carry only a few passengers per pilot.

The FAA said it “will cooperate fully with the Office of the Inspector General’s audit and looks forward to providing information about our extensive safety work in this area”.

In highlighting the challenges for the FAA, the inspector general’s office noted that the existing regulation for aircraft certification that is being used is still primarily intended for traditional small aircraft with a pilot onboard, whereas eVTOL aircraft may be entirely autonomous.

At present, dozens of VTOLs are at various stages of development as manufacturers aim to grab a slice of this keenly anticipated emerging market.

Indeed, Hyundai forecasts the air mobility market will be worth nearly $1.5trn over the next 20 years.

However, Morgan Stanley analysts have also pointed out that regulatory risks are one of the most underestimated for the sector given strict safety requirements, especially for operating in dense urban environments.

The FAA said last week the agency and UK civil aviation authorities have a range of discussions “focused on facilitating certification and validating new eVTOL aircraft, production, continued airworthiness, operations, and personnel licensing.”

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