SkyView Battery Charging before first flight.

[DBRV10]

This is not a Dynon problem.

A first flight DOES NOT need a wingman.

A first flight SHOULD not go out of sight of the runway and should be (besides oil pressure and general fuel flow and CHT limits) ignoring most things other than IAS and altitude.

As soon as any number of alarms go off, even false ones, unless immediately rationalised, like an alarm that is going off like oil pressure at 80PSI and the alarm should have been 100PSI, close the throttle and glide back to the runway and fix it.

Lack of planning and a plan for the first flight is not optional. You do not leave the field until you have confirmed all systems work.

Fortunately even a complete electrical failure is not a reason for a disaster. So long as the magneto's keep firing.

 

[vlittle]

Folks are starting to have opinions that are unrelated to the facts in this case. I will no longer comment.

 

[DBRV10]

Vern, Sure there are many opinions here, but the facts in this case are a First Flight, an obvious parameter which was not checked off on the ground as a system check, before any flight, otherwise the VPX bug would have been found, and I quote;

There were no steam gauge back ups, but one radio lasted long enough to get his wingman to take the lead and bring him back to final approach.

How is this? In Phase one the radius or test area surely can't be that big you need a wingman to get you back to the airport you left from? I can fly a tiger moth within 300 miles of home and not need anything more than clean sunglasses.

I am sorry if my comments have been harsh, and I am not setting about to have a punch-up on the forum, but the facts as presented do make me worry about the serious and realistic approach to a first flight or even the phase 1 period. And with all that considered I do not see, in my opinion, anything failing in the SV system or documentation.

 

[vlittle]

Vern, Sure there are many opinions here, but the facts in this case are a First Flight, an obvious parameter which was not checked off on the ground as a system check, before any flight, otherwise the VPX bug would have been found, and I quote;

There were no steam gauge back ups, but one radio lasted long enough to get his wingman to take the lead and bring him back to final approach.

How is this? In Phase one the radius or test area surely can't be that big you need a wingman to get you back to the airport you left from? I can fly a tiger moth within 300 miles of home and not need anything more than clean sunglasses.

I am sorry if my comments have been harsh, and I am not setting about to have a punch-up on the forum, but the facts as presented do make me worry about the serious and realistic approach to a first flight or even the phase 1 period. And with all that considered I do not see, in my opinion, anything failing in the SV system or documentation.

He was flying out of a Class C airport which requies a clearance to enter.  Without a functioning radio he would have had to perform a NORDO approach into a busy airport.  The chaseplane took the lead for the landing approach as a formation of two (facts).  I think this was a prudent procedure and good planning (opinion).

My first post did not blame Dynon for any failures.  It was in fact a suggestion for improving the underlying architecture or procedures, including the builder's design of the electrical system.

Everything else about the pilot decision making should he left off the discussion because this is not the appropriate forum for human factors, except where the technology can mitigate errors in pilot decision making.

Just to add fuel to the fire.... TCW has a backup battery system that can be charged from a main battery without a battery charger or alternator on-line.  Its a bit more complex to wire in but it solves this issue.  That proves that there are architectural alternatives that mitigate this issue (but may have other consequences).

If it were possible in the hardware, Dynon could implement a 'force charge' function that would charge the backup battery from the main battery even without a charger or alternator online. The whole point of this discussion was to enhance safety by considering the charging issue up-front and perhaps even enhancing it's behaviour in future.

It's turned into a platform of finger wagging by pilots that never make mistakes, except for the spelling mistakes in their postings (oops).

Even my postings about failed switches were taken out of context, as if I knew they were going to fail in flight because they were cheap. Well, they were not cheap, they were sold by B&C and recommend by Bob Nuckolls.

Sorry if facts get in the way of a good opinion war.

Vern out!

 

[dynonsupport]

Just to add fuel to the fire.... TCW has a backup battery system that can be charged from a main battery without a battery charger or alternator on-line.  Its a bit more complex to wire in but it solves this issue.  That proves that there are architectural alternatives that mitigate this issue (but may have other consequences).

The TCW system would have drained his aircraft battery faster during this flight, throwing away energy as heat, meaning everything would have failed earlier, and likely he would have lost his radio. Doesn't sound like he even tried to charge the Dynon battery before flight, so the TCW would have been equally uncharged, and would have made this situation worse.

Again, the Dynon battery is not hard to charge. It does a singular thing- it refuses to discharge a 12V lead acid battery. As long as you have a charger on the battery that keeps it above 12.25V (which is below the 100% charge state of ~12.6V, and WAY below the float voltage of 13.8V), the Dynon will also charge.

In our opinion a "force charge" that will allow it to charge down to 12V will help nobody. Since SkyView uses a switching power supply, if your bench supply can't keep up at 12V, the instant it falls to 11.99V, SkyView will increase the current draw and it will fold back further.

A "force charge" that will charge down to 11V or 10V is sub-optimal, as you will likely discharge your aircraft battery, which means you'll now depart with a dead aircraft battery, which is likely worse! You'd be writing us a different safety concern if we'd done that. Heck, SkyView can operate and charge the backup battery down to 4V on the input power, but we don't do that because that destroys the aircraft battery if left on. We shut off at 10V because it's moments from the aircraft battery collapsing anyway, and it prevents permanent damage.

I fail to see how the TCW is easier to charge- what are you charging it off of that is below 12.25V that is not your dying lead acid aircraft battery? Why would you ever want to charge your backup battery from your main battery? You only ever want to charge your backup from your alternator or battery charger. The "architectural" issue with SkyView is not an issue in our opinion- poorly thought out battery backup systems that will continue to charge a backup battery when the alternator fails are the units with architectural issues.

I still think the message that the SkyView backup battery is limited in charge state is a good idea and will likely help someone someday. I doubt there is anything we could have done to help here.

There's a reason literally every other EFIS company leaves it up to their customers to figure out how to back up the power to the EFIS. It's not easy.

 

[swatson999]

So I'm curious about a couple of things:

...Due to a misconfiguration of the main electrical system (VPX), the alternator did not come online in flight.

Why was this not noticed ON THE GROUND?  The alternator didn't "not come online in flight", right?  It *didn't come on at all*, ever, including on the ground.

There should have been something on a checklist that positively indicated the alternator is charging *prior to taking off*.

Don't know about this installation, but Skyview does indeed come with an ammeter shunt which can be configured numerous ways to help indicate charging or not.

At least on mine, I can see with a single glance at the screen during runup if the amps are positive (charging) or negative (altenator off-line).

How was this system configured in such a way as to not provide this sort of positive cross-check?  And why?

  First flight is a very stressful time and there were a number of other alarms that masked this until the entire electrical EFIS systems shut down due to low volts...

Were these on the ground?  In the air?  All at once?  A series of alarms? 

The *first* alarm should have resulted in an immediate return to the field, right?

And why was that first alarm (or one of the first) not the one that says in your ear "Warning - Power"? (or whatever it says when the amps are negative)

 

[jlakins]

Just to add fuel to the fire.... TCW has a backup battery system that can be charged from a main battery without a battery charger or alternator on-line.  Its a bit more complex to wire in but it solves this issue.  That proves that there are architectural alternatives that mitigate this issue (but may have other consequences).

I just did a G3X system for a friend and used a TCW backup battery so I am familiar with the system.

TCW does not recommend charging from your main battery.
Their older Ni-mh based systems recommend a trickle charge hookup to keep the battery topped off because Ni-mh batteries self discharge.

Quote from the TCW manual
Ground Based Recharging:
To accomplish ground based charging, connect an approved battery charger or power
source to the main aircraft battery and energize the main aircraft power bus by turning on
the master switch, leave all other aircraft loads in their off state.

TCW's new systems are Lithium based and they do not recommend hooking up a trickle charge connection since Lithium does not suffer from the same self discharge issue.

Louis
Read pilots manual 3-11 to 3-13.

Jimmie

 

[vlittle]

Just to add fuel to the fire.... TCW has a backup battery system that can be charged from a main battery without a battery charger or alternator on-line.  Its a bit more complex to wire in but it solves this issue.  That proves that there are architectural alternatives that mitigate this issue (but may have other consequences).

The TCW system would have drained his aircraft battery faster during this flight, throwing away energy as heat, meaning everything would have failed earlier, and likely he would have lost his radio. Doesn't sound like he even tried to charge the Dynon battery before flight, so the TCW would have been equally uncharged, and would have made this situation worse.

Again, the Dynon battery is not hard to charge. It does a singular thing- it refuses to discharge a 12V lead acid battery. As long as you have a charger on the battery that keeps it above 12.25V (which is below the 100% charge state of ~12.6V, and WAY below the float voltage of 13.8V), the Dynon will also charge.

In our opinion a "force charge" that will allow it to charge down to 12V will help nobody. Since SkyView uses a switching power supply, if your bench supply can't keep up at 12V, the instant it falls to 11.99V, SkyView will increase the current draw and it will fold back further.

A "force charge" that will charge down to 11V or 10V is sub-optimal, as you will likely discharge your aircraft battery, which means you'll now depart with a dead aircraft battery, which is likely worse! You'd be writing us a different safety concern if we'd done that. Heck, SkyView can operate and charge the backup battery down to 4V on the input power, but we don't do that because that destroys the aircraft battery if left on. We shut off at 10V because it's moments from the aircraft battery collapsing anyway, and it prevents permanent damage.

I fail to see how the TCW is easier to charge- what are you charging it off of that is below 12.25V that is not your dying lead acid aircraft battery? Why would you ever want to charge your backup battery from your main battery? You only ever want to charge your backup from your alternator or battery charger. The "architectural" issue with SkyView is not an issue in our opinion- poorly thought out battery backup systems that will continue to charge a backup battery when the alternator fails are the units with architectural issues.

I still think the message that the SkyView backup battery is limited in charge state is a good idea and will likely help someone someday. I doubt there is anything we could have done to help here.

There's a reason literally every other EFIS company leaves it up to their customers to figure out how to back up the power to the EFIS. It's not easy.

Yes, no good deed goes unpunished.  I'm perfectly happy with Dynon's method now that my HR-II has a ground power port for the EFIS system.  I published a complete annotated schematic of my electrical system so that my friends (and others) can get a head start on all of these subtle system design issues, or at the very least ask the questions.

Unfortunately, very few avionics techs habituate the E-AB forums, with some notable exceptions.  Many of these subtle issues get lost because the avionics installation is delegated to the pros.

Ironically, I think I was the guy who found the main battery discharge bug from the keep-alive on the D10a in 2005, so I understand the problem with parasitic loads.

At least this wide ranging debate has raised the issue from my original post... Make sure the backup battery is fully charged before flight! I don't really like the suggestion of flying the airplane to fully charge it.

 

[swatson999]

"He was flying out of a Class C airport which requies a clearance to enter. Without a functioning radio he would have had to perform a NORDO approach into a busy airport. "

Or, a NORDO approach at a smaller airport outside the Class C which doesn't require a clearance to enter? Assuming his Phase I area encompassed at least a few of these, right?

 

[rfinch]

It's well documented that the Dynon SkyView battery is difficult to charge on the ground and needs several flight hours to bring to full charge...architectural fault of the SkyView system that makes it difficult to top up the battery on the ground.

Before I was blunt in replying to Vern's misunderstandings and confusion. Now I'll just be rude.

Vern, you're full of crap. You state the Dynon Skyview battery is difficult to charge on the ground and this supposed architectural fault is well documented. Documented where? As Dynon has politely responded to this thread several times, it's not hard to charge at all.

Again, the Dynon battery is not hard to charge. It does a singular thing- it refuses to discharge a 12V lead acid battery.

My first post did not blame Dynon for any failures.  It was in fact a suggestion for improving the underlying architecture or procedures, including the builder's design of the electrical system.

Oh, bullshit. You said there was an design fault in the Skyview system and strongly implied that was a significant contributing factor to your careless friend's near-accident on first flight. And now you're saying Dynon is supposed to take some responsibility of the builder's design of their own electrical system. Your friend and all builders are responsible for their own design...something it seems neither you, nor your irresponsible friend, understand. Birds of a feather flock together.

I will no longer comment.

Promises, promises. Here's a promise. I'll continue to refute your bullshit. You're full of it, at the expense of a responsible company and one of the better ones in the E/AB community.

 

[jakej]

rfinch
There is no need for your kind of comment here, by all means disagree if you must but abuse of a fellow forumite is not a good look.
I get frustrated too with people sometimes especially those who don't read install manuals before asking questions however abuse is not the way to go.  Many of us are here to help others & to learn also.
I am an installer & aircraft builder so my time is valuable & shouldn't have to be spent defusing a situation.
If you feel really strongly about someone's comment either ignore it or pm them to voice your concern, it's a much better look 
IMO Vern is a great guy to deal with and very helpful technically, his input is an asset to us.

Please share your skills or experience with Dynon products nothing else should be of concern here   

Jake J

 

[rfinch]

There is also no need for Vern's continued misrepresentation of Dynon. Everything he's said has been refuted and he continues to blame everybody and everything. He's implied that he uses facts, others use opinions, and that those disagreeing with his nonsense never make mistakes.

Vern's a bullshitter. Plain and simple. His expertise sure isn't evident in this thread.

As for me, this is Dynon's forum. They are welcome to modify or delete anything they like. You post in the form you like, I'll do the same. I don't use happy faces when I call out repeated nonsense.

 

[vlittle]

It's well documented that the Dynon SkyView battery is difficult to charge on the ground and needs several flight hours to bring to full charge...architectural fault of the SkyView system that makes it difficult to top up the battery on the ground.

Before I was blunt in replying to Vern's misunderstandings and confusion. Now I'll just be rude.

Vern, you're full of crap. You state the Dynon Skyview battery is difficult to charge on the ground and this supposed architectural fault is well documented. Documented where? As Dynon has politely responded to this thread several times, it's not hard to charge at all.

Again, the Dynon battery is not hard to charge. It does a singular thing- it refuses to discharge a 12V lead acid battery.

My first post did not blame Dynon for any failures.  It was in fact a suggestion for improving the underlying architecture or procedures, including the builder's design of the electrical system.

Oh, bullshit. You said there was an design fault in the Skyview system and strongly implied that was a significant contributing factor to your careless friend's near-accident on first flight. And now you're saying Dynon is supposed to take some responsibility of the builder's design of their own electrical system. Your friend and all builders are responsible for their own design...something it seems neither you, nor your irresponsible friend, understand. Birds of a feather flock together.

I will no longer comment.

Promises, promises. Here's a promise. I'll continue to refute your bullshit. You're full of it, at the expense of a responsible company and one of the better ones in the E/AB community.

Let me respond.  There used to be a thread on this forum that discussed this issue and how I modified my electrical system to simplify the charging of the SkyView battery. I can no longer find this thread, so I retract 'well documented'. It was at one time, but not anymore.

I also never claimed a design fault, but rather an architectural fault.  This means that it works exactly as intended but did not cover every conceivable scenario. Perhaps 'limitation' would be a better term than 'fault'.  Having a debate on this is like having a debate on any other feature... Except that I supplied an example to support my argument.

As for Dynon taking responsibility for the electrical design of builder's aircraft:  there is a community (aeroelectric forum) that has tirelessly debated aircraft wiring architectures to the benefit of the entire community.  It is very sad that we can't have reasonable debate on this forum for issues related to Dynon's product.

We can't always control the human factors related to pilot decision making, but we can control the technology. I am as protective of Dynon as anyone. I have been a loyal customer for 10 years, and have reported several bugs to help improve the product.  I wrote the interface spec that was adopted by both Dynon and Garmin for the exchange of ADAHRS and Engine data.  I've developed several products that work directly with Dynon's products and one of which was adopted (copied?) by Dynon, plus a flight safety device that is being considered by the ASTM/FAA Part 23 spin avoidance committee for adoption as a standard for general aviation aircraft. Along the way, I managed to be a co-founder of $500M tech company and built a couple of airplanes.

If people are tired of my pontifications, I will happily withdraw from participation in these forums.  I like to inform and educate, but this debate has gone well outside my comfort zone.

Vern

 

[swatson999]

"It's well documented that the Dynon SkyView battery is difficult to charge on the ground and needs several flight hours to bring to full charge.. "

I don't know that it's *that* difficult to charge on the ground. Several people have given their experience with just hooking up a charger and shedding loads and letting SV charge it up. How is that so difficult? It worked fine for me, too.

The whole tenor of the description of the incident seems to have been to lay the blame at everyone else's feet than the PIC: Dynon's battery, the indications on the screen weren't understood because of something or other, the avionics installer, he was flying from an airport in Class C, etc., etc.

So I'll repeat what I and others have asked here:

Why did he not take the time to fully understand his cockpit indications before flying?
Why did he not recognize that his alternator was off-line before taking off?
Why did he not read the manual and understand it?
Why did he ignore "a number of other alarms"?

Sorry, this one is neither an architectural NOR a design issue...it's a pilot issue.

 

[swatson999]

BTW, I don't have the VP-X system, but here's directly from the user's manual:

Upper left: Main and auxiliary (if installed) alternators. The status of the alternator, as well as the amount of current (in Amps) it is producing is displayed. Current will not be displayed if an amps shunt is not installed and connected to SkyView. Yellow cautions and red warning levels are triggered at the values specified during setup. Additionally, if SkyView detects airspeed but does not an active alternator, a fault will be generated.

Upper/lower Right: Main and auxiliary (if installed) aircraft batteries. Displays voltage of the aircraft batteries, as well as the amount of current flowing into or out of the batteries. Current will not be displayed if an amps shunt is not installed and connected to SkyView. When current is available, an arrow next to the Amps reading depicts whether the battery is charging or discharging by the way that it is pointing. An arrow pointing towards the battery implies that current is flowing into the battery. In other words, it is charging. Yellow cautions and red warning levels are triggered at the values specified during setup.

Is this the same display that the pilot had?

 

[lgabriel]

Steve -
SV and VP-X integrate very well, but not perfectly. You have to give up the engine page to see the VP-X page, and you'll be missing info one way or the other depending on how you configure everything.

Everyone else -
What we should all take away from this incident is the importance of having a fully charged SV backup battery, if it's in your plan to rely on it.

 

[swatson999]

I think what we should take away is to know that your alternator is working or not before taking off. And in flight.

Just sayin'...

 

[rfinch]

You know...from the OP's first post describing this first flight, and subsequent posts, it's obvious that the preparation for this flight was woefully inadequate, both the pilot training and ground testing of the aircraft. That lack of preparedness seems to have lead to a near-accident.

Examined with humility and honestly written, this would be ideal for one of those "I Learned About Flying From That" articles that describe a near-accident and lessons learned. AOPA has such a feature ("Never Again") and Kitplanes' version of it ("Error Chain") is focused on experimental near-accidents.

But if there's no lesson learned by the pilot there's no educating others. Too bad in this case.

 

[60av8tor]

Pretty feisty thread . Just throwing it out there - charger hooked up, master switch on, d$ck around in the hangar for 4 hours...voila, fully charged battery. Easy peasy to check bup battery state in the SV menu. Fly every now and then and the bup is simple to maintain. No electrical engineer by any stretch, but I guess I just don't see a real big issue. First world problems are the worst.. ;D

 

[mmarien]

Just a thank you note to Vern.

The Polar Vortex lifted here so I pulled my plane out for a quick trip for coffee and fuel. During run up I switch to the emergency bus to check the EFII system then mistakenly turned off the master rather than the emergency bus. The engine of course kept running but a pile of warnings came up on SV. Before SV shut down and before I realized what the problem was I corrected the switches. The warnings persisted. The main problem was the circuit to the alternator field blew on VP-X.

For a moment I thought that since all the switches were correct, the engine was running and avionics were working I was ready to go. The warnings would take care of themselves - right. Then I remembered Vern's post.