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Synthetic Approach to Your Backyard Strip

Sig600 said:
If you give the masses a great tool, that when misused will potentially kill someone, someone will misuse it and kill themselves.
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Agreed. Is there some particular reason though that your observation is more true for this feature than for any other feature the experimental vendors are providing? As you correctly pointed out, they are prone to being sued no matter what they offer. So far in this discussion, I have seen much speculation that any decision not to offer this feature must be because of legal liability, but the only vendor comments about not offering it seem to rely more on the opinion that it might just be a bad feature.

Even if I think they're wrong, I don't strongly fault them for standing by what they believe to be "right".

--
Stephen
 
fatherson said:
Agreed. Is there some particular reason though that your observation is more true for this feature than for any other feature the experimental vendors are providing?
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I felt considerably outnumbered on this, so avoided posting for a bit, but I'll jump back in with an hypothesis here...

I would posit that it's the similarity in nomenclature, symbology, method, look and feel of what might be called a "synthetic precision approach" or "synthetic ILS" to an *actual* precision approach procedure which could foster a more "lenient" attitude on the part of the user towards accepting and using the feature under the "wrong" circumstances (e.g., in actual IMC, or when flying in conditions which require flight solely by reference to instruments, such a dark night with little or no outside visual reference points).

Imagine a more "advanced" feature in this class...let's call it "Synthetic Precision Approach" or SPA...which I, the experimental avionics developer decide to make available. Here's what I'm offering in the unit I'm trying to sell you: for any runway at any airport, a menu item allows you to select this SPA feature; when selected, the system creates a 3.0 degree glideslope to the touchdown zone, plus synthetic IAF, FAF, MAP and a Missed, Approach Procedure which takes you to some fix/navaid/point of your choice, and it even throws in a "hold". I don't call them that, of course, but instead I call them something else (maybe "Synthetic Initial Fix", "Synthetic Final Fix", etc.). I toss in symbology that looks similar to the ILS "feathers" depicted on an approach plate. I do this all automatically, but maybe you can select a different glideslope. The system includes lateral and vertical guidance (HITS, HSI CDIs, whatever). I tell you "now, don't use this except in VFR, because it's not a *real* ILS".

This is all very doable, and I could even crib up these poitns in conformance with the specs for an ILS approach. "Great!", you say. "That'll help my situational awareness! And I can use it to practice my ILS skills at non-precision airports!" Right?

True, and it might be useful in setting up nice approaches to runways without any ILS.

Think there might be people out there that would use this in IMC? Looks like an ILS, feels like an ILS, I told you it's as accurate as one, and within the FAA specs for one...heck, why not?

What I *didn't* do was survey it, check it for obstructions, terrain clearance, things penetrating those imaginary surfaces that define the approach areas, etc., for every airport in the world.

I propose that I've set up a tool that is *asking* to be used under the wrong circumstances, and likely to get someone killed.

My example is quite a bit beyond a simple "synthetic approach" as we're talking here, but is this not a logical next step in the level of sophistication in such a feature?

OK, I'm ready to get blasted now :) and if I'm wrong, I'll be the first to admit it...but for now, I'm still of the opinion that there are instrument approaches and there are things that are not instrument approaches, and the two should not be confused. :)
 
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Flying Scotsman said:
OK, I'm ready to get blasted now :) and if I'm wrong, I'll be the first to admit it...but for now, I'm still of the opinion that there are instrument approaches and there are things that are not instrument approaches, and the two should not be confused. :)
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Or rather, your opinion seems to be "the two should not be misused", which I think is correct.

Look, you might indeed "get blasted" Steve, but it won't be by me. I really appreciate that you took the time to write such an articulate defense of your apparently minority opinion.

I'm intriqued that my own opinion about this feature still seems to be in flux; there is clearly an internal debate going on inside my own head between two factions:
  1. the libertarian part of my brain is saying freedom is good, trust the customer to use your tool however he deems is right for him, I'm a big boy, you're not my nanny;
  2. the safety-conscious grandfather side of my brain is saying this feature will be both used and misused, Darwin will punish the misusers brutally, said brutality is bad for everyone, my children and grandchildren (and a younger, brasher me) are just as likely to misuse this feature as is some anonymous pilot I don't know, please protect my babies. :)
Hysterics aside (because no, I'm not really such a Dr. Jekyll and Mr. Hyde nutjob), there are quite reasonable reasons to agree with either side in my internal debate.

In the end, freedom wins for both sides though. Dynon and any other vendor who decides not to provide this feature are simply exercising their freedom to sell only those features their conscience permits them to. GRT and the other vendors who do provide the feature, even aware that it may be misused by some, are in effect saying we won't unfairly constrain those of our customers who will use it correctly.

I think this is simply the kind of debate that can never have just one right answer.

--
Stephen
 
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I think you're right about being one of those seemingly endless debates/discussions :)

It must be the systems engineer in me that is analyzing this from a safety perspective, because in my work, safety has to be analyzed for the system as a whole. Each individual part of the systems with which I (and many others here) deal can be perfectly "safe" (i.e., free of hazards, meets its specifications and performance requirements, etc.), and yet when combined, the system as a whole can be shown to not be free of hazards ("unsafe"). It's almost an aphorism that safety is an emergent property of systems. We've seen examples of this in aviation time and again.

And to me, the system includes everything...the plane, the avionics, the ground and space-based navaids, the airport facilities, *the pilot*, ATC, etc.

I appreciate the honest, rational give-and-take on these sorts of issues...because they can root out unsafe practices or components of the system, and then we can deal with those risks.

And of course, as we all know...you can't make things idiot-proof, because idiots can be very clever :). There's always going to be some knucklehead that won't listen to reason, or learn by example, or follow the (very hard-won) lessons and rules. All we can do is try to make things as safe, efficient, usable and capable as we can, and not hamstring everybody else.

So thanks for your nice response (the civility on VAF is a model for other fora to follow, IMHO)...
 
Rainier??

Steve,

I believe that MGL has had its own version of these approaches, called GLS by them, IIRC. They have the ability to do approaches to a waypoint, or airport of your choosing.

Best,
 
Until today, my plan for future upgrades to Tweety was to end up with one or two Dynon Skyview screens, when finances permit. On the way I've installed a D10A to get me started with the glass-cockpit concept. I just found out recently that the D10A has a built-in autopilot too, and that the Dynon servos and install kits are relatively cheap. I was thinking that would be a good "safety feature" to have, and that it would allow the future Skyview upgrade with minimum fuss.

Knowing that I can't do something with the latest-and-greatest Skyview, though, makes me re-think my whole upgrade plan... Knowing that data sets for airports are only going to get more expensive, as the FAA starts charging for theirs too, and knowing that Canadian data is expensive to start with, I want something that allows flexibility.

It seems Dynon has just added a big "minus" to my comparison chart. GRT and MGL are looking better again.
 
One more question for Steve..

Flying Scotsman said:
OK, I'm ready to get blasted now :) and if I'm wrong, I'll be the first to admit it...but for now, I'm still of the opinion that there are instrument approaches and there are things that are not instrument approaches, and the two should not be confused. :)
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Steve, I hope this doesn't come across as a blast in any way. I am fine with your opinion, regardless of whether or not I share it, provided you don't enforce it on me (again, whether I agree or not). But I do have one problem with your analysis that could change the outcome.

You've been very effective at pointing out the risks and pitfalls. Others have pointed out the benefits. Without data, balancing the risks against the benefits is just personal opinion. However, I don't think anyone in this discussion has actually considered the likelihood of abusing this system vs the likelihood of it being used properly. In my experience most pilots are pretty reasonable people that are fond on living to fly another day. Granted, there are hotshots that make you wonder about decision making skills and very few genuinely stupid pilots that just don't understand limits or risks.

Personally, I think I'm in the majority and if I were to set up a synthetic visual approach, I'd sure try it out in day VFR to see if there were any problems before using it...if I could. I suspect the times I couldn't test fly an approach would be very rare. If I found myself inadvertently in IFR conditions, I really think I'd rather have an untested approach than not approach. Without a doubt I could encounter terrain or an obstacle but I think the odds, even with the untested approach, would be in my favor on average (not always - particularly in the mountains - but synthetic vision and the untested approach might save my bacon).

My bottom line is this - I know IF I ever used this option (and I can only think of one airport I occasionally use that doesn't have a published approach) I'd check it out first and make sure I had sufficient clearance to obstructions. If I found myself flying IFR inadvertently (which has happened precisely once in 13+ years of flying) then I'd rather have a tool to help me than just figure it out on my own. There certainly is a risk involved in the later situation but the tool, I believe, lessens the risk.

If your concern is strictly that having the tool would increase the likelihood of flying into situation where using it became necessary or of deliberately abusing it, then for those people, I'd agree with you. For my level of preparedness/caution, I think the tool has far more benefits than risks. And finally, I always love the Jimmy Buffett line, 'there's no dumb *** vaccine' and it seems appropriate here. I'd rather not wait for the too until there is a vaccine.

Sure hope this didn't come across as a slam. You raised good points but incomplete, imo. A risk-benefit analysis needs to weigh both sides.
 
Flying Scotsman said:
I think you're right about being one of those seemingly endless debates/discussions :)


And of course, as we all know...you can't make things idiot-proof, because idiots can be very clever :). There's always going to be some knucklehead that won't listen to reason, or learn by example, or follow the (very hard-won) lessons and rules. All we can do is try to make things as safe, efficient, usable and capable as we can, and not hamstring everybody else.

So thanks for your nice response (the civility on VAF is a model for other fora to follow, IMHO)...
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Steve, you quote above seems to me to sum up most of what the posters, including myself, has said in the above posts.

We shouldn't stop providing tools the 'MAY" be misused just because of a few knuckleheads that "MAY" misuse them. We see your point too!
 
L.Adamson said:
Considering the terrain, I'll take SV over the old methods any day.
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I fly around the Rockies as well and this G600 demo, while nice, does not make me want to run out and buy one.

I fly VFR. I do not fly around the mountains at night or marginal weather conditions. I look outside and see the real terrain.

There are times I would like to disable my terrain warnings on the Garmin 430W.
 
Other Issues

I haven't read all the posts carefully; just skimmed them, so these issues may already have been addressed regarding a hypothetical synthetic approach:

Perhaps my GPS and/or EFIS does have terrain and obstacles, so it could use those in constructing the approach on a 3 degree glideslope, or warn me if it is not able to do without terrain or obstacle problems. However, the GNS 430W manual includes the following warning: "The Terrain feature is for supplemental awareness only. The pilot/crew is responsible for all terrain and obstacle avoidance using information not provided by the 400W-series Terrain feature." It gives a similar warning regarding VNAV. I expect that EFIS vendors providing a synthetic approach include similar warnings regarding the use of their terrain and obstacle features.

Further, it is my understanding that the approach path guidance provided by a GPS is only part of the requirement for an approach to be available. It seems to me that there may also be requirements regarding the condition of the runway, the runway markings, the runway lights, approach lights, etc.

Providing what seems to be the a valid GPS approach to a runway that is otherwise unsuitable for low-visibilty landing may allow some pilots to get into trouble, even it is never used in IMC.
 
For the folks that think this SV tool is a bad idea. I request your opinion on this...

Me. I have found SV has changed the way I fly. Just as xm weather in the cockpit has. And the xm wx has proven to me on many occasions to be completely wrong. Yet I still use it and make decisions in large part often based on the xm wx Im getting.

So I assume you also do not wish pilots to have wx in the cockpit as ill informed, or untrained, or unprofessional pilots, might use it to get themselves in trouble and die. True? And Ill stipulate that this has in fact already happened.

Please provide your reasoning either way and lets test your position.
 
Kahuna said:
For the folks that think this SV tool is a bad idea. I request your opinion on this...

Me. I have found SV has changed the way I fly. Just as xm weather in the cockpit has. And the xm wx has proven to me on many occasions to be completely wrong. Yet I still use it and make decisions in large part often based on the xm wx Im getting.

So I assume you also do not wish pilots to have wx in the cockpit as ill informed, or untrained, or unprofessional pilots, might use it to get themselves in trouble and die. True? And Ill stipulate that this has in fact already happened.

Please provide your reasoning either way and lets test your position.
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additionally add to the list:

If you think handheld GPSs are a bad idea for the same reasons...
 
XM weather is a great tool

in the bag. I NEVER completely trust it to be right. In fact, it gives me a big picture view just like other forecasts and reports.

I have seen it look like I would die if I flew through the stuff I was flying through in nice VMC conditions.

It's just another bit of information for the old bold pilot to help him make it to old.
 
You can come up with literally thousands of examples of other things in aviation that people can misuse.

That doesn't invalidate an argument about the safety of the thousand and first thing.

Your argument seems to be that because some people will misuse a feature/capability/device, there should never be any feature/capability/device that is inappropriate or considered unsafe...because *I* would never use it in an unsafe manner.
 
I'll repeat my earlier question...you're Joe Average Pilot. You have an instrument rating, with modest skills, and you rely heavily on SV now (and it IS a significant improvement over the 6-pack of instruments).

You're in the weather.

Your destination airport is below minima, so you pull up some other airport nearby which you didn't flight plan for, select the "Synthetic Precision Approach" (as I described above) for it.

Ready to risk your life on this "approach"?
 
Flying Scotsman said:
I'll repeat my earlier question...you're Joe Average Pilot. You have an instrument rating, with modest skills, and you rely heavily on SV now (and it IS a significant improvement over the 6-pack of instruments).

You're in the weather.

Your destination airport is below minima, so you pull up some other airport nearby which you didn't flight plan for, select the "Synthetic Precision Approach" (as I described above) for it.

Ready to risk your life on this "approach"?
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You know, we can all ask questions until we're blue in the face. If you are stupid enough to risk you life with anything, nobody can save you from yourself.

Let's move on.
 
RV8iator said:
You know, we can all ask questions until we're blue in the face. If you are stupid enough to risk you life with anything, nobody can save you from yourself.

Let's move on.
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Wow. Sorry I got concerned about making aviation safer.

Thanks for setting me straight.
 
No, but that's now what this feature is about.

It's about helping a pilot maintain situation awareness in his or her airport that has no published approach. You won't be adding a SV approach to your GRT database at an airport that you don't frequent often so why even argue it's unfamiliar?

Yes, it's dangerous if you use it wrong. Yes, it will kill if you use it wrong. We are flying experimental home-built airplanes! There is a elevated risk. You fly the features you feel are safe and if you feel it's not safe, then don't fly with it.

Thank you Greg and Carlos for adding this feature to our EFIS systems. I can't say I will use it since my home airport has a few published approaches but I'm sure it will get used by others.


Flying Scotsman said:
I'll repeat my earlier question...you're Joe Average Pilot. You have an instrument rating, with modest skills, and you rely heavily on SV now (and it IS a significant improvement over the 6-pack of instruments).

You're in the weather.

Your destination airport is below minima, so you pull up some other airport nearby which you didn't flight plan for, select the "Synthetic Precision Approach" (as I described above) for it.

Ready to risk your life on this "approach"?
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Kahuna said:
For the folks that think this SV tool is a bad idea. I request your opinion on this...

Me. I have found SV has changed the way I fly. Just as xm weather in the cockpit has. And the xm wx has proven to me on many occasions to be completely wrong. Yet I still use it and make decisions in large part often based on the xm wx Im getting.

So I assume you also do not wish pilots to have wx in the cockpit as ill informed, or untrained, or unprofessional pilots, might use it to get themselves in trouble and die. True? And Ill stipulate that this has in fact already happened.

Please provide your reasoning either way and lets test your position.
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About three years ago, a twin engine fire bomber crashed on the otherside of the mountain from where I live. It took the lives of three people. A cockpit recorder survived the 208 knot slam into the mountain.

There was a Garmin 396 on board, and the first officer was flying. They were VFR and skirting some weather. The captain was somewhat familiar with the area, and was giving heading and altitude instructions. They had to go lower due to IMC. The first officer saw red (terrain) on the Garmin about 10 miles ahead. He made a comment to the captain, but either the captain didn't hear him.....or.... The first officer didn't restate the upcoming problem or over rule. No CRM.

In this case, I'd be 99.9% positive, that an SV display on the primary flight display would have made a difference. The same for the C-130 at Jackson Hole, the two aircraft with CFI's that hit the same mountain around here, and that airplane that hit the mountain in the Phoenix area two months ago.

The reasons of why all these accidents vary. Some are definitely due to complacent actions by the pilots. Others are just mistakes, or not knowing. Never the less, other crew and passengers don't have to go along with them. A tool such as SV can make all the difference. I've personally had two good friends, and seven acquaintances perish in CFIT.

These people had just planned routine VFR flights too.
 
Hello.

I deleted your recent VAF post about _SHOUTING IN ALL CAPS FOR PARAGRAPHS_ for the following reason(s):

_X_ Civility / Tone
__ Not RV-related
__ Commercial promotion by non-advertiser
__ Mod/Policy bashing
__ Politics / Government
__ Illegal video clip
__ eBay / Barnstormers / etc. (classified-specific rules at: www.vansairforce.com/community/showthread.php?t=8208)

The posting rules are explained in greater detail at: www.vansairforce.net/rules.htm

If you feel the need, please direct comments regarding this to the owner of the site (Doug Reeves). His contact info can be found at: www.DeltaRomeo.com

Thank you.
Doug Reeves (site owner)​
 
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Not you

Flying Scotsman said:
Wow. Sorry I got concerned about making aviation safer.

Thanks for setting me straight.
Click to expand...

I wasn't taking pot shots at you. But if you think that by not providing a tool that does in fact make flying safer because someone may misuse it, then we will just respectfully disagree. You fly without it and I'll fly with it.

No harm no fowl.
 
Flying Scotsman said:
You can come up with literally thousands of examples of other things in aviation that people can misuse.

That doesn't invalidate an argument about the safety of the thousand and first thing.

Your argument seems to be that because some people will misuse a feature/capability/device, there should never be any feature/capability/device that is inappropriate or considered unsafe...because *I* would never use it in an unsafe manner.
Click to expand...

The arguement is quite the contrary - just because someone else maybe stupid and misuse the equipment isn't a reason for responsible pilots to the opportunity to use it.
 
There are three pages of warnings

at the beginning of the Garmin 796 pilot's guide. Among these many warnings, they specifically warn about not relying on terrain avoidance, navigation, weather, etc. as the primary flight information. How would it differ for Dynon to provide a SV approach to a non-instrument airport? It would be similar information, not to be relied on as a primary navigation source, which would, of course, be VFR references. Not unlike the non-certified Dynon GPS not to be used for IFR (only for "situational awareness"). Just my humble opinion.
 
Hello.

I deleted your recent VAF post about _SHOUTING IN ALL CAPS!_ for the following reason(s):

_x_ Civility / Tone
__ Not RV-related
__ Commercial promotion by non-advertiser
__ Mod/Policy bashing
__ Politics / Government
__ Illegal video clip
__ eBay / Barnstormers / etc. (classified-specific rules at: www.vansairforce.com/community/showthread.php?t=8208)

The posting rules are explained in greater detail at: www.vansairforce.net/rules.htm

If you feel the need, please direct comments regarding this to the owner of the site (Doug Reeves). His contact info can be found at: www.DeltaRomeo.com

Thank you.
Doug Reeves (site owner)​
 
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If the concept is a box that shows your projected flight path to the runway, consider the following.

What if you can set up a box where the user defines the maximum and minimum headwind component on final. The system uses that along with GPS ground speed and rate of descent to define the upper and lower portions of the box.

The upper portion is based upon higher surface winds.

Then the pilot can set up where in the box he sets up his approach based upon known surface winds.

Where this comes in as a greater safety aid is engine out. The approach angle is based upon actual flight conditions and conceptually should help reduce over/under shoots.
 
Flying Scotsman said:
Hello.

I deleted your recent VAF post about _SHOUTING IN ALL CAPS!_ for the following reason(s):

_x_ Civility / Tone
__ Not RV-related
__ Commercial promotion by non-advertiser
__ Mod/Policy bashing
__ Politics / Government
__ Illegal video clip
__ eBay / Barnstormers / etc. (classified-specific rules at: www.vansairforce.com/community/showthread.php?t=8208)

The posting rules are explained in greater detail at: www.vansairforce.net/rules.htm

If you feel the need, please direct comments regarding this to the owner of the site (Doug Reeves). His contact info can be found at: www.DeltaRomeo.com

Thank you.
Doug Reeves (site owner)​
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I am glad to see this proactive monitoring and action taken here. If not checked, I can get out of hand quickly.

I appreicate this fourm and those supporting it very much.
 
Flying Scotsman said:
I'll repeat my earlier question...you're Joe Average Pilot. You have an instrument rating, with modest skills, and you rely heavily on SV now (and it IS a significant improvement over the 6-pack of instruments).

You're in the weather.

Your destination airport is below minima, so you pull up some other airport nearby which you didn't flight plan for, select the "Synthetic Precision Approach" (as I described above) for it.

Ready to risk your life on this "approach"?
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In an emergency, yes. And I've done it using air-ground radar. Pucker factor: high.

I'm with Jerry though, you can't save stupid people from doing dumb things.

RV8iator said:
I wasn't taking pot shots at you. But if you think that by not providing a tool that does in fact make flying safer because someone may misuse it, then we will just respectfully disagree. You fly without it and I'll fly with it.

No harm no fowl.
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No fried chicken?!?!?! What am I here for???

RV8R999 said:
The arguement is quite the contrary - just because someone else maybe stupid and misuse the equipment isn't a reason for responsible pilots to the opportunity to use it.
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Valid, but if you're the manufacturer of said system... the first person that kills himself misusing the system has a family that will probably sue you. Even if they don't think of it, 100 strip mall lawyers are going to be in a track meet to convince them they need to. Do you want the liability as a manufacturer? If only we could hold plaintiffs liable for failed lawsuit costs...
 
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Are any of the units being discussed here certified for IFR?

If not, it should not be used as a primary flight instrument in IFR conditions. So an SV or SA (or SPA) approach which is created in the non-certified EFIS cannot legally be used to fly an approach in IFR conditions.

I believe you wouldn't be able to create a user approach in a certified unit.

Yes, I know that wont stop incautious people from doing this, nor will it stop grieving relatives from suing.

On the other hand, it is a great addition to a VFR toolkit in terms of situational awareness.

So, having read 8 pages of this topic, I agree that it is up to each manufacturer to balance the level of risk they wish to take on, and either provide it, or not.

As for us consumers, at least it provides a differentiation between products to help our choice.

The rest is up to the pilot to use these tools responsibly and appropriately. Its what we ask of pilots across all spheres of aviation.
 
Flying Scotsman said:
You're in the weather. Your destination airport is below minima, so you pull up some other airport nearby which you didn't flight plan for, select the "Synthetic Precision Approach" (as I described above) for it.

Ready to risk your life on this "approach"?
Click to expand...

So the best counterpoint scenario is this?
"Ummm, Approach, Since it's total IMC and my dest airport is below approach mins, please cancel IFR. My best bet is to go VFR/IMC into Bob's cornfield."

GRT 1
AFS 1
Dynon 0
 
Sig600 said:
Valid, but if you're the manufacturer of said system... the first person that kills himself misusing the system has a family that will probably sue you. Even if they don't think of it, 100 strip mall lawyers are going to be in a track meet to convince them they need to. Do you want the liability as a manufacturer? If only we could hold plaintiffs liable for failed lawsuit costs...
Click to expand...

I would argue that simply having a Skyview in the panel would give a lawyer one **** of a lot more to drool over. Everyone and their dog has a Skyview, GRT, etc. all showing 3-D terrain. With people growing up to be very used to playing video games on an iPad sized screen, is it really that much of a stretch to see Joe 100-hour VFR pilot buying a Skyview-equipped RV and flying it through cloud whenever he wants to? Just fly the video game until you pop out the other side, right?

Keep in mind that the precision approaches are in there for all of the "official" airports, so there's nothing stopping the same low-time VFR pilot from trying to use one to get into an airport that he's not familiar with. All GRT has offered here is the ability to add your own for the unofficial approaches. Maybe all that's needed is for the unofficial ones to be in a different colour, or a dialog box reminding you that the approach isn't official, or some such.

And really, the biggest risk is Joe 100-hour-learned-on-a-Cessna pilot buying an RV in the first place. :p
 
Dear GRT

Thank you GRT for creating the synthetic approach capabilities. As many have stated, it does in fact increase the situational awareness of a responsible pilot.

Personally, I use the SAP in my GRT Sport on a regular basis during VMC. I do this to increase/maintain my proficiency, and to verify the SAP accuracy. I have been flying with the GRT Sport SAP for about two years and have found that it would have guided me safely to the runway 100% of the time, had I been in actual IMC. I realize the limitations of the SAP which is why I practice with it, and cross check it. As a VFR pilot, I do not want to be in IMC. If for some reason I do find myself in IMC, I feel much more confident that I can safely return to a runway using the features that the GRT has to offer.

It is hard for me to comprehend how this topic has created such a heated debate. As I read this thread, I have to wonder how many of the "anti's" have actual experience flying with a GRT EFIS, and using the SAP feature. If you don?t believe that this type of equipment is beneficial to you, just don?t use it.
 
Mike S said:
Although I have no intention of creating my own approach, (not to mention no idea how even given the info from GRT,) I must say I would do a lot of day clear VAF testing of the approach before I ever tried it at night or in the soup.

As has been mentioned already, Darwin will get involved if folks are not doing things correctly.
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You should never try this "at night or in the soup". It is not the intent nor certification. Doesn't matter how much "day clear VAF testing" you have done.

Folks, we in experimental aviation have lots of freedom. We start pushing the envelope and screw it up. well, those freedoms will cease.

If you declare an emergency, and use your PIC emergency authority to use this approach in IMC and you save the day, well then, you are justifiably a hero. You shoot this approach in the goo just because it's your home field and clip a tree... I better not see your heirs filing a lawsuit on your behalf.
 
Most of you whether for or against having this ability have missed the point. The synthetic approach is a situational awareness tool and not an approach tool. It helps give the autopilot guidance on long straight in descents to a runway and some visuals in the way of HITS and that's it. It was never meant to be an approach tool to use in IFR.

To Carlo's original post, the guys that fly into private strips have other issues to contend with such as seeing the runway from three miles or more out and I doubt any of them use a standard pattern and fly straight in. This enables that user to get a simulated 3deg glide slope to that runway.

If you don't agree with the capability there is a very simple answer....don't use it. But....don't tell us we shouldn't or can't. For or against, you'll never convince each other, let it go. As a longtime and repeat GRT offender this whole thread is silly. If it wasn't for our experimental EFIS manufacturers Garmin wouldn't even be in this game and certainly not trying to copy all their functionality so give all these guys, GRT, AFS, Dynon, & MGL some credit for being creative and setting the bar for the certified world.
 
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Will_S said:
Are any of the units being discussed here certified for IFR?

If not, it should not be used as a primary flight instrument in IFR conditions. So an SV or SA (or SPA) approach which is created in the non-certified EFIS cannot legally be used to fly an approach in IFR conditions.

I believe you wouldn't be able to create a user approach in a certified unit.

Yes, I know that wont stop incautious people from doing this, nor will it stop grieving relatives from suing.

On the other hand, it is a great addition to a VFR toolkit in terms of situational awareness.

So, having read 8 pages of this topic, I agree that it is up to each manufacturer to balance the level of risk they wish to take on, and either provide it, or not.

As for us consumers, at least it provides a differentiation between products to help our choice.

The rest is up to the pilot to use these tools responsibly and appropriately. Its what we ask of pilots across all spheres of aviation.
Click to expand...

GRT, SV, or any of the others do not have to be "certified" for legal IFR. What does certified mean anyway? TSO perhaps? - not required. Smart - maybe. Required - no.
 
RV8R999 said:
GRT, SV, or any of the others do not have to be "certified" for legal IFR. What does certified mean anyway? TSO perhaps? - not required. Smart - maybe. Required - no.
Click to expand...

Given the above information what is the reason that a GPS such as a Garmin 696 or 796 can't be used for a IFR approach. I have talked with a lot of people on the subject and many are doing exactly that but yet the prevailing wisdom is that a GPS must be panal installed and TSO'd to use for approaches or even area nav work. It seems even those with TSO'd unit will actually fly the approach off a 696 given a choice since the presentation and situational awareness is better with a Geo Referenced approach plate.

George
 
sailvi767 said:
Given the above information what is the reason that a GPS such as a Garmin 696 or 796 can't be used for a IFR approach. I have talked with a lot of people on the subject and many are doing exactly that but yet the prevailing wisdom is that a GPS must be panal installed and TSO'd to use for approaches or even area nav work. It seems even those with TSO'd unit will actually fly the approach off a 696 given a choice since the presentation and situational awareness is better with a Geo Referenced approach plate.

George
Click to expand...

I hope that it isn't true that "Many are doing exactly that" if by "that" you mean using uncertified GPS's for primary navigation in actual IFR conditions. if so, then anarchy reigns in the sky, and an awful lot of folks have just decided that the rules don't apply to them....and the rules are there to allow us all to play together. But I digress.....

The instruments (AHRS, attitude indications, Air Data) do not need to be certified,but the GPS needs to be an IFR certified unit to use it for IFR flight. AS Long as you are driving your GRT, AFS, Dynon, etc with an IFR certified GPS, you're good.

I don't have the reference handy, but the EAA has done a lot of work on this,and written some good guidelines that the FAA seems to acknowledge.

Paul
 
2 different issues

For the scenario listed above, I always do my best to plan for a destination with a great approach. If we are talking emergency (below mins, running low on fuel, tried everything else) my default is always to shoot the best alignment procedure of my life to mins(gnats @$$ localizer), reduce descent rate to survivable (me vice aircraft) and go until I break out or hit the deck. Have had to do this once on an ILS, broke out 50 feet below mins...but I think thats better than flying it out of fuel THEN breaking out unpowered!

Second issue, I fly a very expensive and capable military aircraft. We have GPS, and a really darn nice one, but we do not shoot approaches with it. We have radar, but do not use it to shoot approaches with. We have a very accurate radar altimeter too.

We use simple TACAN for our approaches. In practice we use the GPS and Radar to increase SA while using other approved procedures to shoot the approach. I believe any additional tool to increase SA (up to the extent where additions begin to task saturate the user) are all good for us in the hot seat.

Provide tools to make life better, warn against their improper use. If you give a million people a stick of dynamite and a lighter, someone is bound to light it and watch...human nature.
 
You know guys,
MGL has been doing this ever since we released our first Enigma EFIS many years ago. It's an ingrained part of the system. No big deal. We use a very accurate UBLOX GPS with WAAS and RAIM that can put you down within 10 feet or less even without WAAS and you have full facilities to monitor GPS accuracy estimates live.

We call it a GLS approach. You get a row of green crosses at your favourite glide slope to the threshold on the synthetic vision (or a bit deeper - you decide). The crosses are easier to line up compared to boxes and it's also much more identifyable as an approach.
You also get HSI and glide slope indications as you would expect from a normal ILS approach.

Creating a new GLS approach (if it is not in the database) could not be easier.
Simply use our free flight planning program "MGL Central" where you can maintain your own database. You can add a new airport and then add some runways and specify the hard way by entering threshold elevations and positions - our you can simply define a runway using Google Earth which is integrated into MGL Central - find your runway on Google Earth and define a runway using the provided functions - it involves simply clicking on the thresholds in the Google Earth image. It takes elevations from the terrain data (you need to install that for your maps anyway) and works out everthing needed, even the runway designations (which you can still edit if needed).

It can't get much easier than this. We used this to provide GLS approaches to every single little strip in South Africa that we could find.

For most MGL databases ('Navidata") provided by third parties such as Jeppesen, the approaches are in if the source data provides the information.

Lastly: Is it all legal and FAA and so forth ?
No it is not.
But it works. And it works well.

Use it, don't use it. It's there, it's free. If you're stuck one day it can help you. It certainly does help you if you know the data is good (as you have been flying it in VFR and can confirm that it takes you right down to where you need to be).
It's not certified data. That is why you should never use a GLS approach that you have not personally verified as being good. It could be bogus or the runway is no longer servicable. The responsibility lies with you.

Oh yes, we regulary use it coupled to the MGL autopilot to demonstate an automated approach into our home airfield (which does not have ILS and has a narrow runway). Never fails to impress...

Rainier
CEO MGL Avionics
 
RVbySDI said:
Hello.

I deleted your recent VAF post about _SHOUTING IN ALL CAPS FOR PARAGRAPHS_ for the following reason(s):

_X_ Civility / Tone
__ Not RV-related
__ Commercial promotion by non-advertiser
__ Mod/Policy bashing
__ Politics / Government
__ Illegal video clip
__ eBay / Barnstormers / etc. (classified-specific rules at: www.vansairforce.com/community/showthread.php?t=8208)

The posting rules are explained in greater detail at: www.vansairforce.net/rules.htm

If you feel the need, please direct comments regarding this to the owner of the site (Doug Reeves). His contact info can be found at: www.DeltaRomeo.com

Thank you.
Doug Reeves (site owner)​
Click to expand...
I will remember the concept that all caps is defining a "tone" the next time. My post was not meant to be directed toward any one individual. Sorry it came across that way.

Live Long and Prosper!
 
probably stirring the pot...

Just out of curiosity, does anyone know if it's even possible to get a home designed approach approved by the FAA? If it is, is there a list of criteria to do so? Who has the authority and responsibility to design the approaches we do have? I should probably know this, but I don't. Not that I have ever done this, or am particularly interested in doing so.

But the libertarian in me wonders about it.

I mean, I feel I have enough IFR experience and smarts to learn what the FAA uses as criteria for a legal approach, and design one for my airpark that would be as safe as one at Ft Pierce. Elrey Jeppesen didn't worry about the FAA, or CAB as I guess it was in his day, at least when he first started out. He designed his approaches to be safer in bad weather! No one called him crazy or irresponsible, and he made a pretty good business out of it.

I certainly don't have the expertise to design and build my own aircraft, such as Mr. VanGrunsven did. I understand all homebuilt aircraft must be inspected by the FAA or designee before having an airworthiness certificate, but it seems to me if someone can design, build, and fly their own airplane, that's a much more daunting task, fraught with far more risk factors, than a homemade approach.

And most of the world would call those of us who build a homemade aircraft crazy and irresponsible!

just my 2c.
 
Awesome!

Flying Scotsman said:
This might get you started:

http://www.faa.gov/airports/great_l...-Design-for-Instrument-Approach-Worksheet.pdf
Click to expand...

Wow. That is just great! I wasn't planning on doing anything, I really just asked out of curiosity, but I think at our next neighborhood board meeting I might see if there is enough interest for someone (it will probably be me if I suggest it:p) to do the legwork to get an approach approved.

Although now that I think a little longer, my guess is it has been brought up before, and probably the extra cost of the insurance probably prohibits such a thing.:mad:

Anyway, thanks! I have saved all the .pdf files. I've worked with the FAA before with getting a practice aerobatic box, so if the neighborhood wants one, well maybe I'll do the work! Of course, it might take even longer than building the -7...

thanks again,
Damon
 
Interesting thread. :cool:

Can't help but think of a couple friends who lost their lives to Controlled Flight Into Terrain (CFIT) and had they been epuipt with SV, they just might have still been aviating.

SV is great SA.

Proud to use it now. Just darn exciting to see our flying get safer. :)
 
Reviving this thread

I believe the "synthetic approach", also called "VNAV", is a great safety feature for VFR flight. I'd like to better understand the little differences between the SA/VNAV offered by the different brands (Garmin G3X, GRT, Dynon/AFS). My benchmark is the VNAV I regularly fly on a certified G1000, where you can input the desired descent angle (e.g. 3 degrees), and desired TRK, you want to arrive at a future waypoint (or offset from it). This is exactly equivalent to an ILS, in the sense that, irrespectively from your speed/wind/fpm changes, the autopilot will fly the plane along a fixed path in the sky (which is necessary to avoid obstacles). I've never flown any other system so I'm posting here to understand which non-certified system comes close to the VNAV feature of the G1000.

I read the 2015 G3X manual and, on the VNAV chapter, it says that the pilot has to input the FPM descent rate he wish to use to reach a future waypoint at a certain altitude. Then the manual continues saying that, 1 minute before reaching the initial descent point "The descent angle locks to prevent changes in speed from altering the profile." This is not super clear, but I think it means that the system calculate a descent angle using the speed (probably Ground Speed) the plane has 1 minute before reaching the initial descent point, assuming the target FPM descent rate that was input (via the well-know formula that FPM/GS=DescentGradient=DescentAngle*1.7). If this is the case, it is very unstable system, because the pilot has very little control (and awareness) of the actual Descent Angle that the system will fly.

Did I read the G3X manual correctly? Do you know if other systems (GRT or Dynon/AFS) have the same "strange" way to program a coupled VNAV/Synthetic Approach?
 
Comments on the GRT version of Synthetic Approach

Mancival said:
I believe the "synthetic approach", also called "VNAV", is a great safety feature for VFR flight.

<<<SNIP>>>

I read the 2015 G3X manual and, on the VNAV chapter, it says that the pilot has to input the FPM descent rate he wish to use to reach a future waypoint at a certain altitude. Then the manual continues saying that, 1 minute before reaching the initial descent point "The descent angle locks to prevent changes in speed from altering the profile." This is not super clear, but I think it means that the system calculate a descent angle using the speed (probably Ground Speed) the plane has 1 minute before reaching the initial descent point, assuming the target FPM descent rate that was input (via the well-know formula that FPM/GS=DescentGradient=DescentAngle*1.7). If this is the case, it is very unstable system, because the pilot has very little control (and awareness) of the actual Descent Angle that the system will fly.

Did I read the G3X manual correctly? Do you know if other systems (GRT or Dynon/AFS) have the same "strange" way to program a coupled VNAV/Synthetic Approach?
Click to expand...

"Synthetic Approach" on the GRT systems is something a lot simpler/more basic.
If you have an airport as the final waypoint/destination, the you have the option to "ARM Synthetic Approach"

The system asks for your choice of runway (it tries to suggest based on winds I think but winds can change down low). You select the runway.

THEN it builds a 3 degree path through runway centerline, I think starting at/near the touchdown zone( ... think the big bars) out to infinity and makes available an "EXECUTE" button.

Once you press "EXECUTE" and get near it, it will lock on laterally and "capture" the vertical as well. Use whatever power you choose, but I usually pull back to about 10" MP using a 160HP Lycoming with CS prop for about 5-600 FPM descent.

If the autopilot is engaged, it will attempt to fly it right down the center of the "Highway In The Sky (HITS)" boxes. Otherwise the boxes will be there and you can fly it manually.

You can also just "view" the Synthetic Approach (HITS) when doing an ILS. It is interesting to note that at times they are NOT the same.

James
 
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