Boeing Completes 787 Dreamliner 'High Blow' Test
EVERETT, Wash., Sept. 27, 2008 -- Boeing [NYSE:BA] successfully completed a high-pressure test, known as "high blow," on the 787 Dreamliner static test airframe at its Everett factory today. The test is one of three static tests that must be cleared prior to first flight. During the test, the airframe reached an internal pressure of 150 percent of the maximum levels expected to be seen in service - 14.9 lbs. per square inch (1.05 kilograms per centimeter) gauge (psig). It took nearly two hours to complete the test, as pressure was slowly increased to ensure the integrity of the airplane.
"We had every confidence going into this test because of the extensive work we've done on larger and larger pieces of composite - from small coupons to fuselage sections," said Pat Shanahan, vice president and general manager of the 787 program. "Still, it's very rewarding to see a whole airplane being tested and having the results we expected.
"I am so proud of the team that has worked on this program and the progress we are making."
Image Credit: The Boeing Company
The remaining two tests will structurally validate the leading edges and trailing edges of the wings of ZY997 before Dreamliner One can fly. Boeing did not announce a timeline for when these tests will be conducted.
on September 28, 2008 1:50 AM | Reply
This is not really a surprise. There has not been any issue with the structure.
This being said, like any other program, engineers have to make minor adjustments here and there.
But that's business as usual.
One step at a time. That's the way to go.
on September 28, 2008 11:55 AM | Reply
Jon (or anyone reading this), maybe you can help me understand:
If standard atmospheric pressure is already ~14.7 PSI, how does that figure into this testing?
on September 29, 2008 7:44 AM | Reply
The pressure used was 14.9 psig where the "g" stands for gauge, sometimes also called delta-p or differential pressure (dP) when using ambient pressure as reference or datum.
Bottom line is that the test was at 14.9 psi (gauge) + 14.7 psi (standard ambient pressure at sea level) = 29.6 psia (absolute).
on September 29, 2008 12:34 PM | Reply
Excellent, Fred. Thank you.