On Friday, May 10, 2013 8:11:07 AM UTC-4, Don Johnstone wrote:
The system is really a combination of two launch
methods, an auto tow and a winch launch and is just one level of complexity
too much when the proven technology already exists to provide a good
launch without introducing more complex procedures, especially ones which
rely totally on a mechanical/electrical function with no human input or
control.

The opposite of Don, I have ZERO experience with winch launches, so I look at the approach with a completely naive perspective. If you think that my inexperience means that I should not comment on what I see, then stop reading now. I have no opinion, but I have a few questions.

The system is really a combination of two launch
methods, an auto tow and a winch launch...

From my naive point of view, this launch starts out as an autotow. How is this phase of the launch different than a traditional autotow? Waveguru depends on the clutch on the payout winch to modulate the tension on the line.. What are the failure modes for this clutch and what are the consequences? Would it be safer to lock the clutch and start the tow with the line under tension (rather than the truck taking the "running start"? Is a traditional autotow more failure prone and/or dangerous than a winch launch?

Once the autotow phase of the launch is completed, the glider is several hundred feet in the air. All of the bad things that can happen with a winch launch close to the ground have been sidestepped.

(waveguru's method introduces) more complex procedures, especially ones which
rely totally on a mechanical/electrical function with no human input or
control.

Again, naively, in a rapidly developing situation, whenever "time is of the essence" and extremely short, I would generally trust a properly designed and constructed mechanical or electrical mechanism to effect the correct response much more than I would trust a human operator. Is there a reason why a human operator would be more trustworthy in this situation?

Okay. I do have a few observations/opinions:

1)That the payout winch payouts more line and keeps line tension constant when the glider hits lift seems an inherent advantage of this approach when compared to a traditional winch launch.

2)Don's suggestion that traditional winch launching is proven and that there is therefore no reason to experiment with payout winching misses the point. In a country where beefy pickup trucks are common, the start-up costs for payout winching are much lower than traditional winching. Secondly, far fewer humans need to be deployed and coordinated to run a payout winch. The relevant question is "Which is better to use on a dry lake bed, 1)autotow with payout winch or 2)traditional autotow? What are the tradeoffs?