July 23 (Reuters) - The U.S. Transportation Department said on Tuesday it is opening an investigation into Delta Air Lines (DAL.N), opens new tab after the carrier canceled more than 5,000 flights since Friday as it struggles to recover from a global cyber outage, opens new tab that snarled airlines worldwide.

While other carriers have been able to resume normal operations, Delta has continued to cancel hundreds of flights daily of a crew scheduling system.

A massive global technology outage on Friday took down airlines, medical services, TV broadcasts, banks and scores of other business and services around the world, a stunning example of the fragile dependence the global economy has on certain software and the cascading effect it can have when things go wrong.

Financial services and doctors’ offices were disrupted on Friday, while TV broadcasters went offline as businesses worldwide grappled with an ongoing major IT outage. Air travel has been particularly hit, with planes grounded, services delayed and airports issuing advice to passengers.

Earlier on Friday, cybersecurity giant CrowdStrike experienced a major disruption, the company told NBC, following an issue with its latest tech update.

A major cyber outage has grounded flights and disrupted businesses and media organizations throughout the world.

The technology glitch caused chaos on Friday morning with Delta Air Lines, American Airlines and United Airlines issuing statements saying that their flight operations had been impacted. Emergency response systems were down at police agencies and healthcare providers in Phoenix, Arizona, forcing some police and ambulance providers to dispatch cars manually, per The Arizona Republic.