The U.S. Department of Transportation (DOT) has fined British airline Virgin Atlantic $1.05 million after it was found that the carrier repeatedly flew over Iraq in violation of a Notice to Airmen (NOTAM), which designated Iraqi airspace as closed.

The US Department of Transportation reported that an investigation by its Office of Consumer Protection found that Virgin Atlantic flew through Iraqi airspace several times between September 16, 2020 and September 16, 2021.

At the same time, the Federal Aviation Administration (FAA) at that time prohibited US airlines from flying in Iraqi airspace due to fears that commercial airliners could be shot down by surface-to-air missiles.

Although Virgin Atlantic is not a U.S.-registered airline, the flights in question were operated under the numbers of Delta Air Lines under a code-sharing agreement between the two airlines.

Since the planes bore the flight number of a US-registered airline, they were required to comply with the same airspace restrictions as US airlines.

Virgin Atlantic says it became aware of the violation of federal aviation regulations only on September 15, 2021, and immediately ceased flying over Iraq on its codeshare flights.

The British carrier, based in Crawley, a city in West Sussex, Southeast England, operates several flights that fly into Iraqi airspace, including to Delhi and Mumbai.

"As soon as the DOT informed us of the non-compliance issue, our common code flight routes were immediately adjusted," a Virgin Atlantic spokesperson assured. "We have once again thoroughly reviewed and strengthened our systems and processes. The safety of our aircraft, customers and crew has never been compromised and remains our highest priority."

While the US aviation authorities were banning flights over Iraq, many other countries had either already lifted all restrictions or were only banning flights at lower altitudes. The UK Department for Transport has lifted a complete ban on flights over Iraq, so Virgin Atlantic has been building routes over its territory in 2020-2021.

In October 2020, the DOT fined Emirates $400,000 after it was found that the airline had flown over Iran's restricted airspace for 19 days in July 2019.

At that time, Emirates entered into a codeshare agreement with the American carrier JetBlue.

As of today, the FAA has lifted most of the restrictions on flights in Iraq, but an almost complete ban on flights in Iranian airspace remains in place. This ban is likely to limit the number of joint flights between Emirates and its new partner United Airlines, as the Dubai-based airline has been using Iranian airspace extensively and has not had any problems there.

Code sharing is one of the most common types of business agreements between airlines. It allows airlines to sell "partner" flights that they do not actually operate. This, in turn, allows carriers to offer a wider choice of flights within a combined ticket.