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#1
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Jonker JS-3 in Sagebrush
"After 16 years flying the ASW-27, muscle memory was involved. On downwind, the dive brakes were used to adjust appropriate pattern altitude starting from a high pattern entry from overhead, then somewhere on downwind the brakes were lastly put away. But, apparently not put away properly. The JS3 has several detent stops for holding the dive brake open at partial positions whereas the ASW-27 has only one detent at the closed and locked position. "
My question is why was there need to put the dive brakes away in the first place? From my understanding and initial training, the ideal way to fly a pattern is with the dive brakes halfway deployed. Obviously, there will be adjustments to the dive brakes to account for lift, sink, wind.... but at least partial dive brakes should be used throughout the pattern as to make the glide angle in the pattern steep enough to account for the previously mentioned factors. If this is the case then why was there need to put away the brakes on downwind? Is this differences in training, lack of foresight, or just habit? Not trying to critique the pilot just trying to understand the scenario so I can avoid doing a similar thing. |
#2
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Jonker JS-3 in Sagebrush
Wyll Surf Air wrote on 4/16/2019 10:49 AM:
"After 16 years flying the ASW-27, muscle memory was involved. On downwind, the dive brakes were used to adjust appropriate pattern altitude starting from a high pattern entry from overhead, then somewhere on downwind the brakes were lastly put away. But, apparently not put away properly. The JS3 has several detent stops for holding the dive brake open at partial positions whereas the ASW-27 has only one detent at the closed and locked position. " My question is why was there need to put the dive brakes away in the first place? From my understanding and initial training, the ideal way to fly a pattern is with the dive brakes halfway deployed. Obviously, there will be adjustments to the dive brakes to account for lift, sink, wind.... but at least partial dive brakes should be used throughout the pattern as to make the glide angle in the pattern steep enough to account for the previously mentioned factors. If this is the case then why was there need to put away the brakes on downwind? Is this differences in training, lack of foresight, or just habit? Not trying to critique the pilot just trying to understand the scenario so I can avoid doing a similar thing. I rarely use the brakes before I turn final. That way, my turns to base and final are higher than using brakes all the way through the pattern. Perhaps you mean use brakes when you past the end of the runway, a few seconds before turning base? -- Eric Greenwell - Washington State, USA (change ".netto" to ".us" to email me) - "A Guide to Self-Launching Sailplane Operation" https://sites.google.com/site/motorg...ad-the-guide-1 - "Transponders in Sailplanes - Dec 2014a" also ADS-B, PCAS, Flarm http://soaringsafety.org/prevention/...anes-2014A.pdf |
#3
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Jonker JS-3 in Sagebrush
On Tuesday, April 16, 2019 at 1:49:53 PM UTC-4, Wyll Surf Air wrote:
"After 16 years flying the ASW-27, muscle memory was involved. On downwind, the dive brakes were used to adjust appropriate pattern altitude starting from a high pattern entry from overhead, then somewhere on downwind the brakes were lastly put away. But, apparently not put away properly. The JS3 has several detent stops for holding the dive brake open at partial positions whereas the ASW-27 has only one detent at the closed and locked position. " My question is why was there need to put the dive brakes away in the first place? From my understanding and initial training, the ideal way to fly a pattern is with the dive brakes halfway deployed. Obviously, there will be adjustments to the dive brakes to account for lift, sink, wind.... but at least partial dive brakes should be used throughout the pattern as to make the glide angle in the pattern steep enough to account for the previously mentioned factors. If this is the case then why was there need to put away the brakes on downwind? Is this differences in training, lack of foresight, or just habit? Not trying to critique the pilot just trying to understand the scenario so I can avoid doing a similar thing. The complication comes when you want to change flap settings and you have the brakes out. In many gliders, if you let go of the spoiler handle to change from thermal flap to landing flap, the airbrakes suck full open. If you don't notice this things start to go wrong quickly. Some manuals say to select landing flap only when you have the field made so likely on final you might have to close the brakes and then select landing flap. It is easy to run out of hands. UH |
#4
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Jonker JS-3 in Sagebrush
On Monday, April 15, 2019 at 11:27:40 PM UTC-5, Steve Koerner wrote:
As a postscript, I'm not so sure that having detent stops for open dive brakes is really a good idea. I'll think about that some more. I may decide to remove the detents. I suspect that there are other variations of the problem that I just had. It would be especially embarrassing if something like this happened to me again. Thanks, Steve, for your post. Keep the detents. I assume this is the Piggott hook that the other thread is discussing. One day you will be distracted from your routine and you'll take off with the spoilers closed, but not locked, like that 20B that ended in the same Sage brush. Ernst (DG-800 with Piggott hook) |
#5
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Jonker JS-3 in Sagebrush
OK. I'll fess up.
On my first landing in the 29 my hand somehow went from the spoilers to the flaps. I tried to extend the glide by closing the spoilers, but what I did was go into flaps negative. And the ship started falling out of the sky. I figured it out and touched down where I intended, but only because I had 1,000 feet of grass to float over. If there had been trees ... Robin |
#6
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Jonker JS-3 in Sagebrush
Maybe the airbrake lever detents should be shaped so that unintentional extension is impossible, while closing may still be performed simply by pushing the lever forwards. Think saw-tooth dents in the appropriate direction.
If they're cut with this shape, I'd take a metal file to them. Aldo Cernezzi www.voloavela.it |
#7
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Jonker JS-3 in Sagebrush
Il giorno martedì 23 aprile 2019 14:06:14 UTC+2, ha scritto:
Maybe the airbrake lever detents should be shaped so that unintentional extension is impossible, while closing may still be performed simply by pushing the lever forwards. Think saw-tooth dents in the appropriate direction. If they aren't cut with this shape, I'd take a metal file to them. Aldo Cernezzi www.voloavela.it |
#8
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Jonker JS-3 in Sagebrush
Maybe the airbrake lever detents should be shaped so that unintentional extension is impossible, while closing may still be performed simply by pushing the lever forwards. Think saw-tooth dents in the appropriate direction.
If they aren't cut with this shape, I'd take a metal file to them. Aldo Cernezzi www.voloavela.it |
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