CHICAGO -- Boeing Co. said Wednesday that it was going to push back the inaugural flight for its much-anticipated 787 Dreamliner jet by as much as three months, delaying the plane's test flight until the end of the second quarter to allow additional time to assemble the massive aircraft.

The latest delay means Boeing won't be able to begin delivering the airplane until early 2009, instead of late 2008.

VIDEO: Boeing Delays Delivery Of Dreamliner

The Chicago-based aerospace company had hoped the 787's first flight would be conducted sometime at the end of the first quarter.

The 787 program has already been hit with two delays, most recently last October, when Boeing said supply chain and assembly line problems had forced it to push back flight testing until March and delivery to its first customer, Japan's All Nippon Airways Co., at the end of 2008.

"The fundamental design and technologies of the 787 remain sound," Scott Carson, president and CEO of Boeing Commercial Airplanes, said in a statement. "However, we continue to be challenged by startup issues in our factory and in our extended global supply chain."

Many industry observers had anticipated additional delays, which are common with new airplanes.

"The 787 continues to set records for orders, while at the same time management is wrestling with one of the most complex product developments in aero history in terms of both technology and program management," Oppenheimer & Co. analyst Myles Walton told investors Wednesday in a research note.

The 787 is Boeing's first newly designed jet since airlines started flying the 777 in 1995. It will be the world's first large commercial airplane made mostly of carbon-fiber composites, which are lighter, more durable and less prone to corrosion than more traditional aluminum. Boeing says it will be cheaper to maintain and offer better fuel efficiency and more passenger comforts than comparable planes flying today.

But the unprecedented plan to assemble a jet from components manufactured largely by other companies ran into early snags when the outsourcing led to a variety of problems involving contractors in numerous countries. It also was dogged by shortages of fasteners and other small parts that hold large sections of the plane together.

Boeing said it will work with customers and suppliers to determine the impact of the latest delay.

In the past three years, nearly 800 orders have been placed for the long-awaited Dreamliner.

"We are deeply disappointed by what this delay means for our customers," Carson said.

The change will likely impact the company's 2008 financial projections, which Boeing officials said they would update later in the month.

Boeing shares, which topped $107 before the six-month delay was announced in October, fell 71 cents to $77.15 in morning trading Wednesday. That is near their 52-week low of $76.