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#11
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Jonker JS-3 in Sagebrush
Maybe add a red light on the panel when the brakes are unlocked? If you have an UC warning buzzer, there will already be a microswitch on the airbrakes.
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#12
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Jonker JS-3 in Sagebrush
Not the first bird in the sagebrush with spoilers out at Minden..........we got a 20B that was totaled there. Spoilers not locked and sucked open on takeoff! Pilot never did figure it out and put it in the sagebrush, shortly after release. I have made it routine to peek over my shoulder at 300 feet just to insure they are closed. Same on landing when I pull them, just to make sure they both are operating after a DG driver had only one spoiler deploy at Truckee, years ago. Mustle-memory is REAL, it became normal to shove the stick forward, after touchdown in the Genesis-2 in order to get the nose-wheel on the pavement while aiming straight down the runway. After 1000 hours of doing this, I flew an LS3a..........yep, I touched the nose on the pavement because muscle memory told me to shove the stick forward after touchdown. OK, lesson learned, right? Nope, I did it a second time!
The older we get, the more vigilant we must become! JJ PS, I’m thinking spoiler detent’s may be just asking for trouble? Better to keep your hand on the spoiler handle as long as you want them and still need them? |
#13
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Jonker JS-3 in Sagebrush
At 04:27 16 April 2019, Steve Koerner wrote:
I know the pilot well and have had a lot of discussion with him about this.= It turns out that this was the pilot's maiden flight in the JS3 and it tu= rns out that the pilot has a bit of a thick brain and hadn't had enough opp= ortunity to sit in the airplane and get familiar with the controls before s= etting sail. =20 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 bra= kes were lastly put away. But, apparently not put away properly. The JS3 ha= s 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. = =20 By the time the poor SOB got to the base turn position he realized he was a= bit lower than he expected and attributed that to sink. Bringing the turn= around, he concluded that he was still in some pretty nasty sink. His spl= it second decision was to get the airplane down on the deck for the dual pu= rpose of getting into ground effect and secondly to get under the sink (sin= k always has to end at ground level when the ground is itself level). The i= ntention was to attack the perimeter fence fast so as to be able to pop ove= r it then on to runway 30. Plan C would be to land before the fence in the = sagebrush if there wasn't positively enough energy to get over the fence. As you already know from the original poster, plan C, landing before the fe= nce was selected. Not surprisingly, speeding up with partially deployed ai= r brakes caused energy to bleed all the more surely and quickly. At touchdown a ground loop ensued that partly happened on top of the dense = 4 foot high brush. =20 There's now a little bit of fix-it to be done on this beautiful new glider;= nothing big enough to involve insurance companies. When things go wrong there's takeaways... For JS3 flying, one must put eye= balls on the divebrake lever and its detents. It's not just push forward a= nd lock anymore. We've learned that the hard way. =20 The other takeaway relates to adequate familiarizing with a new type. What = I've done in the past with new gliders is to take them home to my workshop = and sit in them for hours just playing with the controls and the instrument= s to make sure that I was totally familiar before taking flight for the fir= st time. That was impractical this time. The program letter specifically r= equired first flight at Minden and we were especially time squeezed because= there were two of us who'd traveled long distance to get to Minden to pick= up gliders and we needed to share one set of probes between two gliders (m= y JS3 arrived without probes); I was nominated to go first being the borrow= er in this instance. =20 Of course, that's all just sort of excuses. None of that should really have= been a problem. I was properly briefed on the dive brake detents by a know= ledgeable instructor and signed off accordingly. That little difference in= the dive brake control design, though, just wasn't sufficiently engrained = in this pilot's brain quite yet. It's unusual to accidentally land out on your maiden flight with a brand ne= w airplane. I'm feeling like a dodo for doing so and sad to have hurt my n= ew bird. Another big thank you to Mike and Tim and to Jim Lee for helping with my re= trieve in that nasty sage brush. =20 As a postscript, I'm not so sure that having detent stops for open dive bra= kes is really a good idea. I'll think about that some more. I may decide t= o remove the detents. I suspect that there are other variations of the pro= blem that I just had. It would be especially embarrassing if something lik= e this happened to me again. Steve, This post took a lot of courage to write. Thank you for your brutally honest analysis. Hopefully, the post will have been worth it, if it prevents just one other new JS-3 pilot from making the same error in the future. Best wishes for quick repairs. RO |
#14
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Jonker JS-3 in Sagebrush
Steve,
This post took a lot of courage to write. Thank you for your brutally honest analysis. Hopefully, the post will have been worth it, if it prevents just one other new JS-3 pilot from making the same error in the future. Best wishes for quick repairs. RO I agree. For all of our talk about sharing mistakes with our peers, from experience I know it's tough to 'fess up. Stuff happens. New situations present themselves, even if you've been flying for 50+ years. And if the latter is true, you're older and perhaps not quite as quick to assess and take the proper action. Kudos for the detailed account, which could save someone else from a similar or even more dangerous situation. Chip Bearden JB |
#15
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Jonker JS-3 in Sagebrush
Thanks for that detail, Steve.
What happened seems to me typical of a safety device causing problems that we frequently see these days. For example, banging your head more often while wearing a hard hat (safety helmet), since it limits peripheral vision while making you taller. I once aborted an ASH26E takeoff because it wasn't climbing. Looking at the wing showed some orange things. "Hmmm, what idiot left them open? Not much runway left, think I'll stop." JJ, doing an engine run-up requires wheel brake, back stick and throttle, three hands? Perhaps this is one reason for the detents. Jim |
#16
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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? |
#17
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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. |
#18
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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) |
#19
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Jonker JS-3 in Sagebrush
Jim,
So, spoiler detent’s were added in order to set the brakes because the pilot needed both hands elsewhere during run up! Then the detent’s resulted in unwanted spoilers on final? How about figuring out another way to set that wheel brakes? I’ve been watching Air Disasters on TV and can’t believe all the crashes caused by some computer geek adding some unnecessary feature. They covered an accident the other night where the copilot accidentally hit the Go-Around button and ended up crashing on the runway! Go-Around Button? The computer geek decided a pilot needed help shoving in the power and pulling the nose up? They crashed a 747 at SFO because of auto throttle didn’t shove in the needed power because the ILS wasn’t working Probably invented by the same Go-Around geek previously mentioned. Let’s not even mention the 737 fly by wire fiasco! I’m to the point that I wouldn’t get on a bird that doesn’t have the stick and rudder connected directly to the controls! I saw this crap coming 50 years ago in the F-111. If the bomb-aim’er made a cross-hair correction, the computer would only accept half his correction! The operator was only one input along with inertial, Doppler, etc. Now we have progressed to the point the operator may have no input at all. The computer thinks were stalling and by god the nose is getting shoved over, period! Good to get that off my chest, I feel much better now! JJ |
#20
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Jonker JS-3 in Sagebrush
JJ - as explained to me by Uys, the idea of the spoiler detent is so that you can secure spoilers open on the landing roll so you dont have to let spoilers close while changing to negative flaps with the same hand and potentially ballooning.
They arent really intended for 'select and leave' in the air - which I would not recommend anyway. The spoilers are adjustable in the normal way, the pilot has the option of setting them in a detente or not. Just wanted to clear up this little red herring on how they are intended to be used, and how they actually work. I did not experience any issue with the spoiler detent use, and flew my test flight pattern with spoilers adjusted in the normal way. 2T |
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