Wichita ? After years of steady declines, demand for Cessna Aircraft Co.’s largest and fastest business jet is on the rise again.

Deliveries of the $20 million Citation X peaked in 2000, when the Wichita company shipped 37 of the eight-passenger planes to customers. But only 14 were delivered in 2005, and last year, just 12.

Now, with orders rising, Cessna will boost production 65 percent by 2010, when it will build about 20 of the jets.

Cessna spokesman Doug Oliver said deliveries of the Citation X fell during an overall decline in general aviation aircraft sales caused by a downturn in the economy and the aftermath of the Sept. 11 terrorist attacks.

In addition, Oliver said, “We’re just coming out of the post-Enron era, I think, where business jets were lumped into this category of corporate largess.”

The business jet market now is on an upswing as more businesses realize corporate jets are a convenient, economical and efficient way to get more done, he said.

A resurgence in Citation X orders is coming from Europe and South America, he said.

“The Citation X still occupies a unique spot in the market,” Oliver said. “It’s the fastest nonmilitary aircraft flying.”

It also faces more competition in its class.

For many years, business jets in the $15 million to $20 million range of the market had been neglected by many manufacturers, said Teal Group aerospace analyst Richard Aboulafia.

“All of a sudden every manufacturer decided to get into that segment,” he said.

The Citation X competes with other large midsized jets, such as Bombardier Aerospace’s Challenger 300, the Gulfstream 200 and Raytheon Aircraft’s Hawker 4000.

While the others don’t have the same speed, they do have roomier cabins.

The trend in the market is toward larger, more comfortable cabins, said Cai von Rumohr, Cowen and Co. managing director.

With the Citation X, “you’re basically paying for the speed,” Aboulafia said. With that, “you get higher (operating) costs and a smaller cabin.”