For the obvious reasons, I invariably get too busy to blog exactly when things get interesting...
Well it’s been a good day to begin with – finished most everything in time for the ops briefing at 10 am, got ready to fly at noon, ended up starting flying at 1 pm…
The helicopter took off and picked up tension as expected at 1000 ft AGL, and the winch controlled the ascent beautifully. As the helicopter ascended, we experimented with various speed and tensions settings, and observed the top-of-cable assemblies to see we didn’t get any unwanted dynamic behavior.
The cable behavior was spectacular, and the pilots reported that station keeping (our main concern) was easier than they expected, and could be performed easily using either visual references or the GPS setup.
Tension read-out was good, but we they’d prefer an analog display since it can vary quite rapidly, and that’s pretty easy to do.
During the ascent, KCSP used the top-of-cable assembly as a tracking target and got a pretty good opportunity to track a km-high target and gauge helicopter-climber separation.
The smooth run was interrupted about 80% into the reel-out procedure, when the anchor pulley failed, and once it failed, it shredded the cable almost instantaneously. The tension during the failure was nominal, so there were no after-effects – it simply disconnected. The helicopter rose a few tens of feet and the cut end of the cable drifted overhead until the pilot laid the remnant on the lake-bed floor.
Since this was a contingency, we shut down for the day, and we will proceed with Laser testing tomorrow. We will also decide tomorrow on how to proceed with helicopter testing – scope and schedule.
Overall, this was not a bad flight – this is what testing is created for – we identified a weak link that can be easily corrected, and gained experience and confidence in the areas of operation. In particular, we had enough reel-out and hover time that know that the areas we considered problematic are actually well under control.