One thing that Boeing has learned through the 787-8 experience is how its gained a reliance on computer models with the correct information inputs into its virtual system. New flight laws keep occurring from real time testing on the flight line. When Boeing started with the 787-8 it had to use metal aircraft data for the virtual design center information base, since it only had data from flying examples in the metal world. The 787-8 took about 3,000 hrs of flight time of testing, before the good to go signal. Then the 787-9 took about 1,500 hours before saying we have it modeled in the virtual system and with the practical mode of flying. Lesson learned in the virtual mode were updated on its design centers computers from the dash 8 to the dash nine. Assumptions made that worked remained and assumption that didn't work were expunged off the data modeling. Those were replaced with actual 787-9 data.
Next Aircraft up is the 787-10 with a longer stretch than the 787-9. Throw another barrel on the fire. One so long that it can't be transported to Everett by the Dream Lifter, so it will be built and remain in Charleston, SC until assembly time.
One out-growth from the 787-8 project is the reliance on the computer model, even when guessing a little. The modeling tells the engineers that close computer results gets it off the ground, and actual flying updates are added to the data, where it provides a pathway on how to fine tune the aircraft with new options. It is a far more complete and efficient way of making complex aircraft over the old trial and error method of test pilots flying, and later having conversations on the flight line. Test pilots still require a rigorous shake down of flying aircraft having immense flying skills. However, those flight line conversations with the engineers are much shorter as a bank of computer servers relay data on what happens during flight maneuvering. How the structure flexes, how the lifting surfaces react and any other in flight characteristics that form anomalies. These results of the test are discovered through duration flying where it goes to the computers and are forwarded to the next model up. The human element remains important as pilot behavioral input, reactions, and expectations are needed for the model. "Human input" to the project must be part of the virtual model!
The 787-9 just did a remarkable performance of gaining flight status after 1,500 hundred hours. Thanks to the 787-8 lessons, and correcting "wrongly assumed designed points" in the virtual model. It is best said that 90% of the model was spot on for the 787-8, and 98% of the 787-9 was spot on from the modeling attributes. The Dash Ten should come in 98.5 to 99% spot on from comparing modeling to real flight tests, completely eliminating the trial and error curve entirely, even as the 787-8 had already accomplished.
In spite of all the white noise, the 787 project has created from press reporting. The big news is found indoors at the Boeing design center, where it will pull together its 777X model, A computer design with all the lessons learned, since WWII for its 777X flying wings. Boeing will know before the 777X takes off for its first flight, what it will do. The test pilots will confirm the model and offer valuable advice for making the aircraft a pilot's aircraft. That is the import part of selling it into the future, what the pilot has to say. I remember how Mike Carriker came off the first 787-8. He was was an engineering hero. His eyes were lit up like an eight year old boy at Christmas with his first airplane toy. The thing flew just like it did in the lab. It was the beginning of something new for Boeing. The virtual model actually flies like "we imputed the information into the computer". The computer model removes 98% of trial and error flight testing.
Wind tunnels are important confirmation and refinement points in design. Pilots are for validation for flight characteristics and the human interface advancements. Mike, being both an accomplished pilot and engineer melded his professional expertise in both the design center and flight line.They are not just there to come back alive as found in the 1950-70's. They are important for the human interface of the machine for all its future pilots.
The 787-8 was five years extra in coming for the engineers, but that effort would have taken 20 years using 1970's technology or not at all. The 787 did a hole-in-one shot and did not lay-up short for a chip shot and a put. Mike Carriker is both an engineer and master pilot where he spent time both indoors at the design center, and on the the flight line. As most Boeing Test pilots now have that dual role. It's the only way to get the virtual world correct. Now bring on the 777X and the 787-10!
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