Odd thing that happened today

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Nomore767
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Odd thing that happened today

Postby Nomore767 » Thu Apr 23, 2015 10:03 pm

Wondering if anyone can add some thoughts on an odd thing that happened when I was flying my RV-12 today.

At run-up I was checking the rpm drop from the ignition modules. I switched one off at a steady 4000 rpm to watch the drop. As I did so my fat finger also caught the other module and for a split-second both were off and the engine faltered until I quickly switched both back on. The engine never stopped.
After cussing myself I checked everything and all seemed normal except that Skyview rebooted. I repeated the engine run-up and checked the ignition modules again and the parameters were all normal. On the second repeated run-up Skyview froze and rebooted normally.
I was about to return to the hangar but on the way pulled over to a side area and spent about 15 minutes checking things over, as I would have done at the hangar anyway. Everything seemed normal and I couldn't see anything out of order.

On a 5000' runway I applied full power and all parameters were normal so I continued the takeoff and climb out was normal. Throughout the flight everything was normal except after about 15 minutes the Skyview suddenly went blank. It rebooted and stayed on for several minutes. I decided to return to the field which I'd kept close.
The Skyview went blank and then rebooted. This time it stuck at the opening page. Normally as the RV-12 logo comes up you hear it say "Dynon Skyview", this time it stuck on that so it was "Duh-duhduhduh etc" instead of Dynon. When it blanked I also lost the radio.

As I approached the field I cycled the avionics switch and got the radio back. I checked all c/bs and all were fine. Skyview came back and stopped at the RV-12 screen. I checked for traffic, announced joining the pattern and flew it all the way to landing with no instruments at all. The engine was fine and so I used my experience with the plane to reduce power and slow to familiar looking speeds/sounds, and attitude. I lowered the flaps which are a johnson bar. I kept the speed to what I felt was a bit higher than normal and it squeaked on slightly farther from the threshold than normal.

After shutdown I felt the screen and it did feel a bit warmer than usual but I did hear the cooling fan switch off with the master switch.
I waited about 15 mins to see if it needed to cool down and it didn't seem like it was ever really much warmer than usual.
I restarted Skyview using it's own internal power (master off) and it booted up normally. I shut down and repeated a couple of times and all seemed normal.

I'm wondering if the Skyview got overloaded trying to restart itself in the air? It had more problems each time until it finally hung up on the start-up screen. After total shut-down do you think that it cleared itself and was able to start normally?

When I inadvertently switched off the adjoining ignition module on run-up what might that have done to the Skyview as far as telling it to reboot, if anyone knows?

I did have Foreflight on my iPhone as back-up to navigate and I'm currently trying to decide how to best back-up Skyview, other than having a second screen, which might also have had the same issue as the other screen? I'm thinking iPad or iFly GPS but haven't got there yet. Any thoughts?

It was my clumsy finger which caused the problem but I'm interested in any thoughts as to what Skyview did to itself from anyone with any experience with it.
I'll contact Dynon tomorrow for their input too.
Last edited by Nomore767 on Sat Apr 25, 2015 8:33 am, edited 1 time in total.

Wm.Ince
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Re: Odd thing that happened today

Postby Wm.Ince » Thu Apr 23, 2015 10:14 pm

Does your SV have a backup battery?
If so, is it fully charged?
I would perform a test on the backup battery.

JMTC
Bill Ince
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Nomore767
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Re: Odd thing that happened today

Postby Nomore767 » Thu Apr 23, 2015 10:23 pm

Wm.Ince wrote:Does your SV have a backup battery?
If so, is it fully charged?
I would perform a test on the backup battery.

JMTC


Bill,

Yes my Skyview has the back-up battery. After engine shut down there were no caution or warning messages and I went into the diagnostic/settings area and checked as much as I could there also. No warnings, anomalies or indications of anything untoward.

There is a back-up battery test screen which I checked and it said I had 45 minutes of back-up power available.

The only other time I've ever seen my screen blank was at Vans when the CFI and I were looking at the screen with the plane in the hangar using it's own power (master off) and I think we spent too long doing that and ran it down quite a lot. When we started up a c/b popped and I was told this was because it was trying to charge the back-up battery and that it does that sometimes. I've never seen it since, although I've never left it on back-up for more than a very short time because of this.

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FastEddieB
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Re: Odd thing that happened today

Postby FastEddieB » Thu Apr 23, 2015 10:36 pm

Not familiar with either the RV12 or the SkyView.

But typically the ignition switches are simple grounding devices for each ignition module. As such, I don't see how they could affect other electronics at all.

Maybe a coincidence?
Fast Eddie B.
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Nomore767
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Re: Odd thing that happened today

Postby Nomore767 » Thu Apr 23, 2015 10:40 pm

Eddie,

Could the split-second where both modules were off cause a power interruption such that Skyview was temporarily unpowered triggering a reboot?

Normally it would be booted and shutdown via the master switch but if a power interruption occurred and the engine was still running it could have been confused into trying to start but the normal start conditions weren't there? :(

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Re: Odd thing that happened today

Postby Wm.Ince » Thu Apr 23, 2015 11:34 pm

One more question.

When you started the engine, are you absolutely sure the generator c/b was pushed in (closed)?
Without gen power, the SV will automatically switch over to backup battery.
When the backup battery has depleted to a known level, the SV will shutdown and go black.

To me, this sounds like a SV power problem.
Bill Ince
CTSW
Retired Heavy Equipment Operator

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FastEddieB
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Re: Odd thing that happened today

Postby FastEddieB » Fri Apr 24, 2015 6:29 am

Nomore767 wrote:Eddie,

Could the split-second where both modules were off cause a power interruption such that Skyview was temporarily unpowered triggering a reboot?

Normally it would be booted and shutdown via the master switch but if a power interruption occurred and the engine was still running it could have been confused into trying to start but the normal start conditions weren't there? :(


Again, the ignitions should be totally isolated from the rest of the electrical system.

Check out the schematic for your plane, if you have access to one.

This is for my Sky Arrow:

Image

Ignition modules and switches are to the lower right, #19 and #18 respectively. Note zero interconnection with anything else.

Note: with the new "SoftStart modules" there would be a single connection from the modules to the starter solenoid, not depicted in the diagram. Still, without the starter engaged that circuit is by default open.

Anyway, maybe the SkyView interfaces in some way I'm not aware of. But, in general, ignition circuits in piston airplanes are designed to be isolated from everything else.
Fast Eddie B.

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Re: Odd thing that happened today

Postby SportPilot » Fri Apr 24, 2015 7:31 am

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Last edited by SportPilot on Thu Aug 20, 2015 5:53 pm, edited 1 time in total.

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FastEddieB
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Re: Odd thing that happened today

Postby FastEddieB » Fri Apr 24, 2015 7:51 am

CTLS schematic:

Image

A bit oversimplified since some items are not identified.

The only connection between the ignition and the rest of the electrical system is "A".

Not sure what that is. Ammeter?

Still, does not look like any manipulation of the ignition switches can affect downstream flow to the electrical system.
Last edited by FastEddieB on Fri Apr 24, 2015 7:58 am, edited 1 time in total.
Fast Eddie B.

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Nomore767
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Re: Odd thing that happened today

Postby Nomore767 » Fri Apr 24, 2015 7:55 am

Jim,

I have looked at the 720/740, even the 520. That, or an iPad, would back-up navigation but I'd not have any EMS or engine indications and I'd lose the ADHRS for airspeed and altitude. Some pilots use them as a primary whereas for me it would be strictly backup.

Not sure if the iFly offers those instruments? I think Garmin Pilot does. I have a Bad Elf GPS to plug into my iPhone for Foreflight and it would also work in an iPad.

Funny, I was just talking to my hangar neighbor before the flight about a backup and he was surprised not even a compass. Little did I know my next landing would be minus engine instruments, altimeter and airspeed!

Nomore767
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Re: Odd thing that happened today

Postby Nomore767 » Fri Apr 24, 2015 7:58 am

Eddie, thanks for that info.

Going to the plane today and I was going to my mechanic anyway for some other items.

I'm going to download the last hour of Skyview time and send it to Dynon and see what they think.

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FastEddieB
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Re: Odd thing that happened today

Postby FastEddieB » Fri Apr 24, 2015 8:04 am

Wild guess...

I guess the SkyView gives RPM info?

If so, and it gets that data from the ignition modules, maybe turning them both off "confused" it?

Like I said, just thrashing around here!
Fast Eddie B.

Sky Arrow 600 E-LSA • N467SA

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Re: Odd thing that happened today

Postby SportPilot » Fri Apr 24, 2015 8:10 am

.......
Last edited by SportPilot on Thu Aug 20, 2015 5:53 pm, edited 1 time in total.

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dstclair
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Re: Odd thing that happened today

Postby dstclair » Fri Apr 24, 2015 10:26 am

I did have Foreflight on my iPhone as back-up to navigate and I'm currently trying to decide how to best back-up Skyview, other than having a second screen, which might also have had the same issue as the other screen? I'm thinking iPad or iFly GPS but haven't got there yet. Any thoughts?


Guess it depends on what you want to backup. The Garmin Pilot app has a simulated six-pack mode and there may be other apps for the iPad that have similar features. Don't know if iFly has this.

It's a bit pricier but you could go with a Dynon D2 "Pocket Panel" for around $1K. It provides a real AI in addition to GPS computed altitude, ground speed, etc. Don't have to permanently install so no LOA needed. An independent review of the prior generation D1 was on Avweb: http://www.avweb.com/news/features/EFIS ... 989-1.html.
dave

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Re: Odd thing that happened today

Postby VL Roberts » Fri Apr 24, 2015 1:36 pm

FastEddieB wrote:CTLS schematic:

Image

A bit oversimplified since some items are not identified.

The only connection between the ignition and the rest of the electrical system is "A".

Not sure what that is. Ammeter?

Still, does not look like any manipulation of the ignition switches can affect downstream flow to the electrical system.


If the RV electrical system is set up like your CT schematic , if an engine start was attempted with the avionics master switch on, wouldn't the avionics experience a voltage drop when starting?


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