KEFLAVIK -- When ZA002's sistership, ZA003 (N787BX), flew into Eglin Air Force Base for hot and cold soak testing in April, flight test crews rolled the 787 into the C-5 Galaxy sized hangar, shut the doors, and turned down the thermostat.
When you're chasing crosswinds at Keflavik Airport in Iceland, a dial to control the weather is a luxury not afforded the crews accompanying ZA002 (N787EX). For the 787's first round of international remote testing, flight test teams had to bring their patience and the list of Plan B ground tests should Mother Nature not cooperate.
To give a sense of the moving target that is crosswind testing, as of last Monday, Boeing first planned last week's 787 event for Thursday to include an opportunity to watch ZA002's maneuvers from a taxiway next to the runway. As the week rolled on, it became apparent Thursday's winds wouldn't materialize and the testing was shifted to Friday afternoon.
By Thursday afternoon, the Friday afternoon crosswind flight had turned into Friday morning crosswind flight with a low probability of a second block in the afternoon. As I waited at the rental car counter at 6:45 AM on Friday having just stepped off an Icelandair 757-300, ZA002 was climbing out of 10,019ft Runway 02 to start nearly five hours of testing that would evaluate the stability and control of the aircraft. The second 787 test aircraft crabbed through the wind performing full stop landings and missed approaches as the METAR showed sustained winds blowing at 27kts and gusting to 39kts.
To put those figures in context, American Airlines allows its pilots to hand fly their largest aircraft up to a 30 knot crosswind component.
For the 787, which has dual heads up displays (HUD), pilots will be able to see the flight path vector without looking down at the primary flight display. For further control in low visibility take off and landing (LVTO) situations, the flight director guidance cube and flightpath vector symbol on the HUD will provide visual cues to pilots. This allows the pilot to fly the apporach by keeping the flight path vector at the desired descent angle for a stable touchdown.
By mid-day, ZA002 was back on the ground and ready to meet the assembled group of Icelandic media and this lone aviation blogger. As we arrived at the aircraft, which was parked at a dedicated spot on the southeastern side of the field, the winds began to pick up again, with spitting rain and winds strong enough to get the Trent 1000s bouncing as the fans looked as though they were spinning at idle.
Our hour with ZA002 was significantly abbreviated as flight test crews scrambled to pre-flight 787 and take advantage of the steady increasing winds. ZA002 with its door closed and chocks pulled waited on the ramp. When you're waiting for the green light from Mother Nature to fly, sometimes it's just best to close your eyes for a moment and grab a quick snooze.
While the winds were most certainly howling, they weren't howling in the right direction, gusting just short of the required crosswind component needed for testing. A couple hundred feet above the runway the winds were sufficient, but as the closer the 787 would have gotten to the grooved asphalt runway, the weaker the winds got curtailing any chance of a second block.
So goes another day in flight test.
ZA002 is expected to ferry back to Boeing Field on September 8.