ORLANDO, Fla. -- Oil company BP used a cheaper, quicker but potentially less dependable method to complete the drilling of the Deepwater Horizon well, according to several experts and documents obtained by The Orlando Sentinel.

"There are clear alternatives to the methods BP used that most engineers in the drilling business would consider much more reliable and safer," said F.E. Beck, a petroleum-engineering professor at Texas A&M University who testified recently before a U.S. Senate committee investigating BP's blown-out well in the Gulf of Mexico.

He and other petroleum and drilling engineers who reviewed a log of the Deepwater Horizon's activities obtained by the Sentinel described BP's choice of well design as one in which the final phase called for a 13,293-foot-long length of permanent pipe, called "casing," to be locked in place with a single injection of cement that can often turn out to be problematic.

A different approach more commonly used in the hazardous geology of the Gulf involves installing a section of what the industry calls a "liner," then locking both the liner and a length of casing in place with one or, often, two cement jobs that are less prone to failure.

The BP well "is not a design we would use," said one veteran deep-water engineer, who would comment only if not identified because of his high-profile company's prohibition on speaking publicly about the April 20 explosion aboard the Deepwater Horizon or the oil spill that started when the drilling rig sank two days later.

He estimated that the liner design, used nearly all the time by his company, is more reliable and safer than a casing design by a factor of "tenfold."

But that engineer and several others said that had BP used a liner and casing, it would have taken nearly a week longer for the company to finish the well -- with rig costs running at $533,000 a day and additional personnel and equipment costs that might have run the tab up to $1 million daily.

BP PLC spokesman Toby Odone in Houston said the London-based company chooses between the casing and liner methods on a "well-by-well basis" and that the casing-only method is "not uncommon."