dHarban wrote: Ed,
While the ALES rules make this 10 percent stipulation, it is not likely that current practice results in strict compliance with this.
I log all of my flights and I do not fly in a manner which is intended to gain any advantage from kinetic energy at the end of shut-off. In fact, I us the Altis switches and reduce the shut-off altitude settings to be certain that I am in compliance. That said, for a 700 watt average input Supra E (Geared Neu 1110) I consistently recorded altitude gains after motor shutoff in the 32 to 35 meter range with maximums over 40 meters. When I was flying that plane I used a cut-off setting of 175 meters for 200 meter contests.
My heavier Maxa is powered at about 600 watts (static) -- 500 watts in flight -- and it consistently exceeds the cutoff altitude by about 23 meters.
The lighter Maxa is powered at about 450 watts (static) and it consistently exceeds cutoff altitudes by about 16 meters.
While I am not sure it makes THAT much difference in the ESAP context, these variations are material and they are from planes which are not optimized or flown to optimize altitude gain after cutoff. In competition it DOES make a difference -- 30 meters is good for about 90 seconds with a Supra or Maxa. And the difference will be exaggerated when lower launch altitudes are selected i.e. 30 meters on top of 150 instead of 30 on top of 200. Further, it can be demonstrated that excess altitude gains far in excess of those I have observed without any weight penalty to the plane. The Supra, for example, could have easily been taken to over 1000 watts with a simple prop change -- no increase in plane weight. And the expected zoom by someone flying for maximum gain would easily exceed 50 meters.
Again with the variation reasonably expected from winch launching and the fact that the SAP allows equipment configurations which are capable of very substantial launch altitudes in excess of the typical launches seen in contests, it probably doesn't matter for LSF tasks. But it WILL for ALES comps.
Happy Landings,
Don
Don, I am surprised you are pushing this point but
since you want to talk launches, let's talk launches. 40 meters beyond 200 is a 20% overage. OK. This seems to be a big issue for you as it seems you have set up your gliders to exceed the target launch height and you want to bring this up as a concern.
Let's see if there is any historical precedent for this concern in the LSF, AMA or SAP history.
I go to run SAP tasks or to fly in a TD contest that qualifies for SAP credit. I am flying my Spirit or BOT or some other entry level to midrange pure glider, You launch your Uber moldie off the same winch I am using. I am hitting 350 feet and you are hitting 700 feet. You are launching 100% higher than I am.
Let's say we are both flying Supras. I launch to 500 feet and you launch to 700 feet based on your greater talent. I see this in contests all the time even when people are flying the same plane. And no one declares the guy launching high is violating any rules of the contest, or is disqualified for SAP credit.
This was never a concern in the SAP or winched TD contests, but it is being raised as a concern for ESAP? Why is a possible 20% variation of ESAP launch a big deal for you but a 50% to 100% variation (or more) for string launch is not a concern?
Absolute launch height is irrelevant, has always been irrelevant and should remain irrelevant based on the traditions established by the SAP and AMA rules. SAP does not define a maximum launch height nor does AMA nor have I seen this at any TD contests that I have ever attended.
The SAP defined the maximum launching equipment that could be used. The ESAP sets the maximum target setting on the altitude limiter. Neither defines the launch height, just the profile of the launch equipment. And so ESAP is following the tradition and the method set by the SAP and AMA.
What about over launching in ALES contests? Well, that is why we have rules and CDs. If a CD is concerned about a 20% launch variation then he will impost the appropriate controls to address it. AMA doesn't require this. SAP doesn't require it for TD contests so why should it be such a big deal for ALES and ESAP?
ALES has created the most uniform launch system that has ever existed in soaring under AMA rules. It is not absolutely precise because it does not need to be precise. But it is WAY more consistent than anything that has ever existed in the string launch world for AMA TD or SAP purposes.
So why are we discussing this? Perhaps you plan to suggest that we modify the SAP to impose a launch height restriction on SAP tasks? The devices exist to do it, so why don't we do that? The answer is that it is irrelevant, it has always been irrelevant and it should remain irrelevant. We don't do it in TD and we are not likely to do it in ESAP.
Hopefully the horse is now totally dead along with the topic of launch height variation.
It has been said in this thread that there are less and less big TD contests so it can be harder to meet SAP task requirements. Well, the cost of a high end glider that can launch as high as the high end moldies has placed this out of the price range of the average guy. Maybe if we imposed launch limits on TD contests more people could afford contest grade planes and there would be more contests.
Not suggesting that we should actually do this for TD, but at least ALES is bringing more uniform launching to the contest world and you can hit that height with an RTF Radian with a $50 upgrade on the prop and the battery. Anyone can launch to the target height. Now it is all about soaring and landing skills.
