It was 2 a.m. on a stormy summer morning.

As the thunder rumbled in the sky, we were led out of a sprawling terminal building through a narrow side door and down a staircase into the pouring rain.

A waiting bus quickly filled up with soaked passengers dragging carry-on luggage.

After a short ride across the dark tarmac followed by another storm-battered trek, we finally entered the freezing cabin of an Airbus 330 jetliner.

Smiling China Southern Airlines flight attendants welcomed us on board, greeting us as if we were excited vacationers about to take off for our dream destination, instead of frustrated, tired and grumpy passengers.

As we settled into our randomly assigned new seats, things turned eerily quiet.

Half of the plane -- the original passengers booked onto the airline's 8 p.m. flight -- seemed to have long fallen asleep during their agonizing wait, while the other half -- those of us re-booked from a canceled 7 p.m. flight and moved onto this one -- were too exhausted to make a sound.

The arrival of a second busload of drenched passengers was followed by a lengthy, silent wait on board -- with no updates from the cockpit.

It was almost 3 a.m. when the pilot announced our impending departure thanks to improving weather.

Our plane finally roared into the starless skies at 3:08 a.m. -- more than eight hours after the scheduled departure time printed on my air ticket.

Hopeful start

All signs pointed to a smooth journey when I checked in for flight CZ3547 to Shanghai on a recent Tuesday evening at the bustling Baiyun International Airport in Guangzhou, a southern Chinese metropolis long known as Canton in the West due to its former spelling -- which also explains the airport code CAN.

Keenly aware of the country's notorious flight delays, I kept checking a popular flight-tracking app geared toward air travelers in China installed on my phone.

Its information echoed that of the check-in agent: inbound aircraft had already arrived and weather conditions looked good at both origin and destination airports.

More promisingly, the app's algorithm put the probability of an on-time departure at 90% -- "What a lucky break," I thought, for a flight whose average delay had been 108 minutes in the past month.

Looking forward to a late night reunion with old friends over street snacks in Shanghai after an easy two-hour hop, I arrived at Gate B231 shortly before the 6:20 p.m. boarding time.

Across the tarmac in the distance, a cluster of tower cranes dominated the horizon.

An even bigger new terminal is under construction and slated to open in 2016 at China's second-busiest airport, which saw more than 50 million fliers pass through its existing terminal last year.

Massive growth

Decades of breakneck economic development have brought exponential commercial aviation growth, quickly propelling China to the No. 2 position in the global flight market, trailing only the United States.

But all the shiny terminals and airplanes aside, China's reputation among frequent fliers continues to sink thanks to the country's abysmal on-time performance, with the busiest hubs in Beijing, Shanghai and -- to a lesser degree -- Guangzhou often competing for the title of the world's most delayed airport.

Meanwhile, nothing happened as our scheduled boarding time came and went.

As our 7 p.m. departure time approached, some passengers started gathering around the counter to inquire about the flight status -- and only then did we hear the most dreaded of all Chinese airport phrases: "air traffic restrictions."

It's an all-purpose, vague term that can mean anything from bad weather to radar malfunctions, which may lead to less efficient aircraft movements ordered by China's already overly cautious controllers.

Lately, however, it's apparently meant only one thing: military drills.