VNAV with skyview HDX

DY691

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Good morning to all
I just received my new ultra light WT9 machine equipped with a skyview HDX and an autopilot.
after a few flights where i could select vnav mode.
since 2 or 3 flights this function is well present on the HDX but is not selectable, a problem on this function?
Thanks for your help.
Guy
 

DBRV10

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You need to have your destination set up with a vertical profile configured. When you are approaching the destination and below the synthetic glide slope you should get the GS indicator appear beside the HSI, then you can arm VNV.

Download the installation manual and the pilot user guide. This will cover setting up the map/nav functions and how to use the HSI and GS features.
 

airguy

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To expand a little on the above - you will not be able to activate the VNAV portion until you have a glideslope depicted next to the HSI and you are below the glideslope. The glideslope will not display until you are within range of the airport - if you select a target 100 miles away you won't get the glideslope until you are maybe 15-20 miles from it, then it will appear and you can arm VNAV.

This function is also only available for charted airports - not user waypoints.
 

DY691

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Thanks for your information airguy, I'll try again on my next flight.
Sorry for my English, but I didn't understand Jakej's answer RTFM
 

jnmeade

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Thanks for your information airguy, I'll try again on my next flight.
Sorry for my English, but I didn't understand Jakej's answer RTFM
Read The xxxx Manual. Some think using vulgar language via initials gets you by, others think it's still vulgar. You may not want to use this to the vicar's wife if you fear you may have to interpret your own words. I'm obviously in the camp of less colorful language.
BTW - be careful. RTM - read the manual - is fairly objective and neutral. RTFM - read the xxxx manual - if often used in a derisory tone, like, "hey,dummy, aren't you smart enough to use the resources at hand". Also, the F word seems to have different connotation not only between age groups but within countries and cultures. In other words, use with some appreciation for your usage and audience.
 

DY691

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Read The xxxx Manual. Some think using vulgar language via initials gets you by, others think it's still vulgar. You may not want to use this to the vicar's wife if you fear you may have to interpret your own words. I'm obviously in the camp of less colorful language.
BTW - be careful. RTM - read the manual - is fairly objective and neutral. RTFM - read the xxxx manual - if often used in a derisory tone, like, "hey,dummy, aren't you smart enough to use the resources at hand". Also, the F word seems to have different connotation not only between age groups but within countries and cultures. In other words, use with some appreciation for your usage and audience.
Thank you for these explanations jnmeade
I don't actually get much out of this advice from Jakej, but that's the thing about the forums...
I wish you a good day.
Guy
 

skysailor

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Dynon Support says you will get the VNAV glideslope when you are 5 minutes from the top of decent profile with the current firmware. On the previous firmware version it was shown most of the time which is the way I prefer it.
 

DY691

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Thank you for this information
I didn't read anything like that in the literature.
Hopefully Dynon will revert back to the old version...unless there's a good reason...which I want to know about.
Good night.
Guy
 

DBRV10

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Read The Factory Manual was the term we used in our Engineering and automation business for 20+ years. :)

And a word of caution. Unlike a certified instrument approach, it is possible for the GS to run you straight through the side of a mountain. This is a DAY VFR tool only. Let me repeat that in a different way. NEVER USE IT IN IMC

The descent path is defined by parameters established by the pilot in MAP SETUP > VS REQ’D. There, the pilot defines a height above the airport or runway and a distance prior to the airport or runway threshold, thus establishing an intended destination point. The pilot must also enter a desired descent angle in degrees. A target descent path is then calculated which rises from the defined destination point upward toward aircraft at the angle specified. The resulting descent path is somewhat analogous to a traditional glideslope. However, it is mathematically calculated only and does not assure terrain or obstacle clearance.
 

jakej

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Read The xxxx Manual. Some think using vulgar language via initials gets you by, others think it's still vulgar. You may not want to use this to the vicar's wife if you fear you may have to interpret your own words. I'm obviously in the camp of less colorful language.
BTW - be careful. RTM - read the manual - is fairly objective and neutral. RTFM - read the xxxx manual - if often used in a derisory tone, like, "hey,dummy, aren't you smart enough to use the resources at hand". Also, the F word seems to have different connotation not only between age groups but within countries and cultures. In other words, use with some appreciation for your usage and audience.
I am NOT the vulgar guy, ”Read The Factory Manual“ is sometimes used when it may appear that someone obviously hasn’t done that. It‘s not the man I’m targeting it’s the situation.
’We’ are here to help where we can however sometimes those asking the questions find it too easy to just post without at least reading the manual first.
DY 961 - please don’t take it personally 😉
ps- if some people don’t understand or get what they need from the manuals then that’s acceptable to me - then go ahead & ask the questions, i figure we will help where we can.
 

jnmeade

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Thanks for the education. AT 76 years of age and after 30 years in the military and 40 years in aviation, this is the first time I've EVER heard of "read the FACTORY manual". Obviously, many of us have not gotten the word so the point is still clear - be careful how you use RTFM because everyone I know of will take it in a vulgar manner. OK - I'm done with the topic - just want to make the point that the vicar's wife will still not be persuaded about the FACTORY in any environment I've ever heard of.
 

Corefile

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Read The Factory Manual was the term we used in our Engineering and automation business for 20+ years. :)

And a word of caution. Unlike a certified instrument approach, it is possible for the GS to run you straight through the side of a mountain. This is a DAY VFR tool only. Let me repeat that in a different way. NEVER USE IT IN IMC

other then getting a BS FAA cert - what is the difference that it’s going to put you into a side of the mountain? Aren’t they both using WAAS gps that have the same exact level of accuracy. I’m not not proposing anyone use it - but also question that the non IFR is so inaccurate it would put you into a side of a mountain
 

DBRV10

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Quite simply, the VNAV vertical guidance generated by the VS REQD is a vertical path to a user selectable point above, before or at a waypoint. If that path happens to pass through a mountain top, it will not care less.

A vertical profile (LNAV+V, LPV etc or a ILS) generated by an IFR navigator with say a Jepesson database will be on an instrument approach and the terrain clearance is assured by that. You will not get a GS unless it is surveyed and approved. This is not some BS FAA certification thing.

As for WAAS and accuracy, assuming you are getting even a non WAAS you will be accurate enough but the point of the certified Navigators to a TSO146 or equivelent standard is more to do with integrity and exclusion of the GPS satellite data. If I can try to say this in simple terms, a WAAS GPS accurately thinks it is exactly where in 3D you are, where as the TSO146 navigator knows it is where it says you are and if it becomes unhappy with the satellite information it lets you know it is unhappy.

So effectively if you use the VS Required vertical profile in Skyview, it will be very accurate, just like the TSO 146 navigator, so damned accurate that if you create a profile and azimuth that places you through the very tip of a pointy mountain, then you will most certainly hit it and die right on that tip. Its accurate enough all right. But that is not the point. It is that there is no terrain clearance capability. It will do exactly what you ask it to, safe or dangerous. This is not an IFR tool. Let me say this again.....NEVER USE IT IN IMC. Clearly my point was missed previously. If you do not understand what I am saying please just trust me on blind faith. This is a DAY VFR tool only.

If you want to use an autopilot for lateral and vertical nav, get the right equipment which includes but not limited to, heated pitot, redundant screens and ADAHRS, backup batteries, a TSO146 GNSS Nav, and an instrument rating. If not stick to DAY VFR only. And just for the avoidance of doubt, I am deadly serious about the DAY bit too. This is not a tool for night ops. You must navigate with clearly planned tracks, lowest safe altitudes etc. If you have planned properly and your vertical path is meeting the safety requirements for navigation at night, then use it only on that planned route. If you do something ADHOC, you need to be careful in not becoming complacent.
 

Corefile

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So the skyview VFR route that goes through a tip of a mountain is somehow not visible on the screen and there is no terrain warning? Wow I didn’t realize that Dynon was lacking such basic features - even my iPad with foreflight has that. You are being a bit hysterical - NO ONE IS SUGGESTING TO USE IT FOR IFR . But stop with the hysterics that if you fly at night or god forbid did VFR into IMC and needed to get out - that you would not be able to use the Dynon to navigate with.
 

jnmeade

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"the right equipment which includes but not limited to, heated pitot, "
A heated pitot may be considered desirable but for part 91 operations in the U.S. it is not mandatory. FAA FAR 91.205(d)
 

DBRV10

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So the skyview VFR route that goes through a tip of a mountain is somehow not visible on the screen and there is no terrain warning? Wow I didn’t realize that Dynon was lacking such basic features - even my iPad with foreflight has that.

Well it is visible on the screen..........IF it is accurately depicted in the database. Have you ever flown past something in VMC and not seen it depicted on the database? Probably not. But I have, so it can happen.

I am not being hysterical. Some people, including your comments suggest that this kind of "rule evasion" from the Instrument Flight Rules are quite OK. I have met plenty of them. I also know of dead people for doing just that. Do I need to be hysterical to post links to the fatal accident reports of this kind of thing? I can, but I am sure you can find a dozen or more in a matter of minutes if you try.

This is not a negotiable topic Corefile. There are plenty of folk that will take your comments and say yeah she is WAAS so what is your problem.

Be a professional pilot, even when flying dat VFR is my motto. YMMV.
 

airguy

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I'm of the opinion that David can get a bit on the preachy and hysterical side - but I'm also firmly in his camp on this topic, and I am old and cranky so I cut him some slack. :cool: We've both been on the Dynon forums since 2008, and I've been beta-testing Dynon hardware for Dynon since 2016 and I'd be surprised if David has not been doing the same - as the TV commercial says "We know a thing or two because we've seen a thing or two". There are too many people who see the VNAV function as a poor-mans IFR tool, which it certainly is not.

The Skyview VNAV function DOES NOT provide any lateral guidance or terrain clearance. It is quite capable, and quite happy, to give you a descent directly through a mount ridge or other high terrain between you and the airport, as David noted. It's a VFR only tool.

The certified IFR navigator will give you lateral and vertical guidance to take you AROUND obstacles rather than through them, based on a surveyed path and a verified database - that's the reason that IFR flight requires the certified navigator. It's not an issue of WAAS or not - it's an issue of a surveyed safe route that guarantees terrain clearance.
 
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Corefile

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Apparently you knuckleheads either choose not to read the part where multiple times I said I was not suggesting to use non certified IFR or you are just straight up trying to twist my words. All I was challenging is the hysterical rant of death and destruction that the VFR Dynon is going to fly you into a mountain the instant you go IMC - I’m not talking about doing it on purpose (please read that 3 times and don’t twist my words) - I was just trying to back off the hysterics and acknowledge that the modern day VFR WAAS based navigation is very accurate. Yes if you program in a route that goes through a mountain and you fly it all the way to terraform you will die - but you will have visual and audible alerts that you would have ignored - that does not make it less accurate. I could make the same accusation that your hysterics is going to put someone at risk - if someone accidentally flies into IMC - and read your rant - they might be afraid to use a very capable tool to navigate safely back to VFR. So get off your soapbox, You are not the righteous all knowing you dream about. Again I NEVER said to use it as an end around the regs or proper IFR.
 
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