"Because all U.S. airports have closed, air shipments are unable to continue from Taiwan to the United States," a spokeswoman at Taiwan's Chiang Kai-shek International Airport told Reuters.

"With the information we have on our hands, we cannot tell when cargo flights will resume," she added.

The disruption of product shipments from Taiwan is part of a sudden shutdown in electronics supply chains going into and out of North America after hijacked jetliners were crashed into the World Trade Center towers in New York and the Pentagon in Washington on Tuesday, resulting in mass destruction and probably thousands of deaths. Commercial air travel was immediately shutdown by the U.S. government.

U.S. semiconductor companies, along with other industry manufacturers and suppliers across the United States, attempted to cope with the shocking attacks and grounded aircraft. Many chip suppliers clamped down on security and attempted to assess options for keeping business running while the shocked nation struggled with the attacks (see Sept. 11 story).

Air shipment is the backbone of most semiconductor supply chains. The industry will most likely cope with a temporary shutdown, but concerns exist about isolated part shortages and the impact on the recession hitting many equipment sectors. For at least today, air transportation is expected to be disrupted with U.S. government officials attempting to decide when to resume flights.

While some industry activities are being put on hold in the wake of Tuesday's tragedy, other events are scheduled to go on as planned. In Taiwan, the annual Semicon Taiwan trade show is still set to open on Monday (Sept. 17) in the Taipei World Trade Center and Grand Hyatt Hotel. A spokeswoman for Semiconductor Equipment and Materials International (SEMI) said the San Jose-based trade group is proceeding as planned with the annual chip production show.

In the U.S., officials with the Networld+Interop show in Atlanta this week said the event will go on as planned despite the terrorist attacks Tuesday, while the Audio Engineering Society Convention scheduled for New York City, beginning next week, remains tentatively scheduled.

"At the moment, we're going ahead as planned," said Roger Furness, executive director of the Audio Engineering Society in New York on Tuesday. The event is set to start Sept. 21 (Friday) and conclude on Sept. 24.

"We're revisiting the decision every hour. Everything is very confused at the moment, and there is no clear indication of what is going to happen in the world in the next 24 hours," Furness said.

Taiwan exports grounded

In Taiwan, electronics and semiconductor managers were trying to assess the immediate impact of grounded flights to the United States. More than 90% of the chips and other electronics products produced at the Science-based Industrial Park in Hsinchu--Taiwan's "Silicon Valley"--are exported to the U.S. market, according to park officials. In just the first 24 hours following the shutdown, 277 shipments worth $7.2 million have been delayed, estimated officials.

In total, Taiwan is the world's leading supplier of LAN cards, monitors, mouse devices, notebook PCs, PC motherboards, scanners, and related products, according to the MarketIntelligence Center (MIC) of Taipei.

The island is also the home of the world's largest silicon foundry companies-Taiwan Semiconductor Manufacturing Co. Ltd. (TSMC) and United Microelectronics Corp. (UMC). It also makes a significant number of other chip products, such as DRAMs, EPROMs, flash memories, ROMs, switching chips, among others.

"There are great concerns that a large number of products to be shipped to the U.S. will be seriously hit due to the shutdown," said F. C. Tseng, vice chairman of TSMC, the world's biggest silicon foundry.

According to the officials in Hsinchu, the Science-based Industrial Park would lose an average of $3.3 million for each day that shipments are delayed, assuming that this month's exports are comparable to July's total of $98.6 million. Sales are generally higher in September than in July, so the losses could be greater.

In addition to the immediate disruption in trade, the attack has thrown cold water in the face of hopes that the U.S. market would recover in the fourth quarter, providing long-awaited relief for the Taiwan electronics industry's depressed sales.

"Everybody was hoping the Christmas shopping season would boost demand," said Mike Tsai, president of Powerchip, a maker of dynamic random access memory chips. "Now it seems that any pickup in the DRAM market this year is unlikely."

Still, some company executives were less worried, believing that the effects will be temporary. "Of course, this is going to have an effect on the global economy," said Stan Shih, chairman of the Taipei-based Acer Group, a major supplier of PC systems and laptop computers. "But the impact wouldn't last long," he added.

--Additional reporting provided by Faith Hung in Taiwan and Darrell Dunn in the U.S. for EBN, a sister publication of Semiconductor Business News.