During the month of April, RC501, the first of what is now five 747-8F test aircraft, spent the middle portion of the month at Edwards Air Force base in California performing take off and stability and control evaluations.
Around April 10, say program sources, the aircraft underwent its certification max brake energy test, which saw the freighter – loaded to its maximum takeoff weight of 975,000lbs – slam on its Goodrich-built carbon brakes just before V1 speed transferring all its generated energy into the ground-down disk brakes, heating them to more than 2,500 degrees Fahrenheit (1,400 C). Boeing says the aircraft was able to stop 700ft shorter than first anticipated.
Boeing published its own video (above) of the test on Wednesday.
Certification requirements prohibit emergency services from moving before five minutes after wheel stop to simulate a real-world incident that accounts for dispatch time at an airport. Carbon brakes have made these RTO tests significantly safer over the years as the previous generation of steel brakes would catch fire, posing a greater risk to the crews conducting the tests.
For the sake of comparison, I’ve posted the original 777-200 rejected takeoff test from 1994/95 certification campaign as well. A second interpretation of the same test presents a significantly different tone, naturally attributable to artistic liberty, but the juxtaposition is notable.