As the Discovery, Enterprise and Endeavor make their last flights, we at Tecplot look back at the role of 3D visualization in the space shuttle program. So today, a little trip down “memory lane” . . .
NASA’s Space Shuttle program first took off in February 1977, but not on an independent flight. Instead, NASA attached it to a Boeing 747 as a test flight. How fitting, then, that the last time our three shuttles are airborne will be via a piggyback ride on a 747.
So, why the piggyback?
When NASA’s space shuttle program was born, engineers had to study the fluid dynamics of more than launch and re-entry. With a launch pad in Florida and a landing strip in California, they needed a way to get the shuttle back east for the next launch.
A piggyback ride, of course.
One problem: this presented unique fluid dynamic challenges. At that time, NASA engineers probably used the linear panel method and a great deal of wind tunnel testing to study the flight characteristics of a 747 with the attached shuttle and stabilizing fuselage. (These were the days before Full Potential code or even Charlie Boppe’s three-dimensional WIBCO code.) To overcome these difficulties, stabilizers were added to the tail assembly to overcome the pitching moment when the shuttle was on top. Also, a tail cone was added to the back of the shuttle for drag and buffet reduction as well as to protect the orbiter engine nozzles. (Read more about this on SpaceFlightNow.com.
In a testament to the ingenuity of NASA engineers, the shuttles are still being piggybacked the same way they were 35 years ago. (You can read more about piggyback techniques here.)
An even bigger role for 3D visualization
After the Challenger disaster, NASA immediately began a major effort to understand every fluid dynamic aspect of takeoff and re-entry. But at first, there simply wasn’t enough computing power to learn much. By the 90’s, though, that was finally changing and NASA began taking full advantage of their new capabilities.
As Dr. Scott Imlay of Tecplot said, “During this time period, in many ways, NASA drove the advances in CFD.” Much of this, he says, was done with OVERFLOW grids which were developed in the early 90′s by Pieter Buning, Dennis Jespersen and others. Pushed to understand the flow field around a complex object traveling over Mach 2 (with humans aboard), these pioneers required entirely new methods of 3D visualization.
Tecplot’s history with NASA, then, is a long and happy one. It goes all the way back to the days that Mike Peery and Don Roberts started the company.
Laughing, Mike says these early R&D projects from NASA AMES meant he and Don “… Went from eating canned beans for dinner to the occasional meal that included ground beef.” We’re proud that with NASA, we’ve been able to push the boundaries of CFD visualization.
The end of an era
Discovery was carried to Dulles Airport, just west of Washington, DC. It will become an exhibit in the Smithsonian Institution. Enterprise will be piggybacked from its previous display in the Smithsonian to New York to become a permanent part of the Intrepid Sea, Air and Space Museum. And Endeavour will be displayed at the California Science Center in Los Angeles.
As the end of the shuttle program was announced, representative Gabby Giffords Tweeted, “Atlantis Space Shuttle closes a proud chapter in our history of space exploration. Looking forward to the next.” We especially like the second sentence of that quote.