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rjtjrt

Well Known Member
What is the position of the various EFIS re in flight reset ability.
One of the advantages of the Garmin 900/1000 9is its ability to reset in flight if needed. Aparently Avidyne could only be reset (rebooted) on ground.
What is the position with non certified gear such as MGL Odyssey, Dynon, etc?
Also any news on when MGL Odyssey available?
John
 
Dynon can be rebooted in flight ... just remove power, then repower it.

Seams to be ok, even if rebooted during lazy 8's.
 
n468ac said:
Dynon can be rebooted in flight ... just remove power, then repower it.
Click to expand...

Certainly, but as an embedded systems type guy - it depends a lot on how Dynon implemented their hardware watchdog and what happens after that "press a button in the next 30 seconds or we'll power down."

The most likely case you'd want to reboot would be because of some sort of software bug (a bug that is keeping the GUI locked up but still leaving the watchdog alive). In that (plausible) case, it is quite possible you'd be stuck waiting for the built in battery to run down.

I dig my dynon, but unless the've been very careful in their software (certainly possible) you can't guarantee that just killing the main power will cause a reboot.
 
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rjtjrt said:
What is the position of the various EFIS re in flight reset ability.
One of the advantages of the Garmin 900/1000 9is its ability to reset in flight if needed. Aparently Avidyne could only be reset (rebooted) on ground.
What is the position with non certified gear such as MGL Odyssey, Dynon, etc?
Also any news on when MGL Odyssey available?
John
Click to expand...

Garmin needs a reset button ?
Jeeze.... :D

Rainier
CEO MGL Avionics
 
Rainier
What is the position with your systems re reset/reboot in flight? Possible or impossible?
I must say I am very impressed with your products, especially the ability to scan charts/topo maps and put them into your display.

John
Melbourne
Australia
 
GRT No Problem

You can reboot the GRT EFIS screen(s) in flight by holding down the first and last buttons. This does not reset the AHRS so it's a non-issue. Mine are on their own SCB's, one with the AHRS, so I could do a power-down reset if needed. That would be best to do while on autopilot, but it can be done, too. I have the AHRS power supplied by both screens' SCB's, so I can reboot either one completely without affecting the AHRS and it feeds serial data to each screen.
 
rjtjrt said:
Rainier
What is the position with your systems re reset/reboot in flight? Possible or impossible?
I must say I am very impressed with your products, especially the ability to scan charts/topo maps and put them into your display.

John
Melbourne
Australia
Click to expand...

Our stance is to have a watchdog to detect a hung system. This is not 100% effective of course since watchdogs tend to be "stupid".
Typically, in most of our systems we have a watchdog that is part of the CPU and a seperate one that is outside of the system (usualy as part of the power supply monitoring circuitry).
Resets are usualy generated as a result of something unpleasant on the power supply bus which tends to result in an emergency shutdown of the system and a rapid restart after that. This is necessary to protect important system data that could otherwise get corrupted, i.e. we don't allow the processor to run if power conditions are marginal. Apart from that, practically everything that is of importance data wise is stored in static memory chips that have a seperate backup supply. Expensive but very effective.

Hung systems due to a software malfunction are very rare. While it is not possible to rule this out (after all we are only human), we follow the somewhat unusual dictum that every single byte of software that runs on these systems MUST be written in-house. This includes everything. No 3rd party software, drivers or anything else (including difficult things like USB host drivers, operating systems, file systems etc) are allowed (we even write our own compilers from scratch and make our own development systems).
While this does not prevent bugs, it does make finding them a lot easier and faster since you are in full knowledge of every tiny aspect of the system.

So, we never had a reset button on our systems. Of course, the BIG reset button is the power cycle. You can do this at anytime, no problem. It is recommended that it is done when you are in reasonable stabilized flight if you would also be reseting the AHRS (which is always external with our systems). This will allow the AHRS to find its orientation near instantly.

From experience gained so far, I think it is safe to state that the majority of issues (by far) are hardware related. Perhaps a bad solder joint somewhere or iffy connector or a chip that gives up the ghost for some unknown reason. That happens. Software malfunction is almost a non-event compared to this.

Right, let me get back to work, have to get the ARINC on the new Odyssey sorted out...

Rainier
CEO MGL Avionics
 
Enigma ok power on/off in flight...

Our first flight with the Enigma I was working out the sensor issues and had uploaded an update without loading the corresponding OPS update. The ASI maxed out at 102 MPH. I cycled the avionics master off then on and everything rebooted A-OK within a a few seconds.

On a note:

The Enigma has a lot more operator input possible than Dynon or GRT thanks to the personalization of the screens and being able to upload custom Raster maps. This is great for customizing your system to your needs. I really like the ability to create my own displays with the Info I use the most.

On the other hand- If you don't upload the screens properly (i.e- follow instructions) and take some responsibility for understanding the system, things won't work right (duh).

So, I really like the Enigma, but if you want someone to build a panel for you and just fly and not 'play' with the system understanding how it works- you might not appreciate all the potential there is in the Enigma.

Regards,
 
Rebooting

Just one experience~ my D-10-A went down just moving it around at home, in my hands. I couldn't get it to reboot and called Dynon. They tried work arounds which didn't and finally asked me to remove the battery. This worked but wouldn't be practical in flight. Caused me to rethink a little. So I've got an AFS 3400 also, with no connections between the two, and a turn coordinator. Seems modern electronics are extremely reliable but crashes can occur. Bill
 
During Phase 1, I did inflight reboots of both my GRT Display Units and the AHRS - reboot and alignment was no issue at all.

Paul
 
chelton reboots in air

during phase 1 we did plenty of in-air reboots of the cheltons and had no issues
 
Do you have the battery backup? I had to remove the battery once to reboot after factory guys couldn't get me up and running over the 'phone. My display had frozen in grey mode. Bill
 
Just one experience~ my D-10-A went down just moving it around at home, in my hands. I couldn't get it to reboot and called Dynon. They tried work arounds which didn't and finally asked me to remove the battery. This worked but wouldn't be practical in flight.
Click to expand...

That is one reason why I much prefer having a dual-buss system on the plane instead of a battery in the D10A. I like being able to shut things down on my own terms.
 
Sam: You think we or Dynon could make up an interrupt switch? Or program a hard reset even with the battery in place and charged? Bill
 
When our products are not equipped with the internal battery, simply cycling power to the unit will reset it. This can be done in-flight, and the attitude will re-acquire within seconds of bootup.

A "hard" reset with the battery installed isn't easily done, though Bill's experience is highly abnormal. In most cases, should an EFIS's software run away or hang, a watchdog process will cleanup after it and restart the unit. But even that really never happens. I don't think we've received a single report of an unit that has "hung up" in-flight.

I'm not sure exactly what Bill experienced, but, over thousands of units, many with internal batteries, we've had maybe 1 or 2 incidents like this where not having the battery would actually have improved the situation. But we HAVE had quite a few more reports from customers who have made it down thanks to their battery backup being available when their electrical system has failed.
 
To Dynon support: Thanks for following this thread and for your reply. I'll keep the battery in given the customer reports you cite. I really do like the unit and hear good reports from friends who fly it. Bill
 
Maybe the question should be asked a different way. I don't think the Garmins or Avidyne require reboots during flights because of any software issue, but what happens if there is an unexpected disruption to the power to the gyros (and EFIS) while in motion---Can they re-align themselves? In the case of the Garmin, gyros can re-align themselves while in motion while Aviddyne and Meggit cannot.

So to re-phrase the question, if there is a disruption to the power of the gyros in each of the respective EFIS systems, can they re-align themselves while they are still in motion?
 
w1curtis said:
Maybe the question should be asked a different way. I don't think the Garmins or Avidyne require reboots during flights because of any software issue, but what happens if there is an unexpected disruption to the power to the gyros (and EFIS) while in motion---Can they re-align themselves? In the case of the Garmin, gyros can re-align themselves while in motion while Aviddyne and Meggit cannot.

So to re-phrase the question, if there is a disruption to the power of the gyros in each of the respective EFIS systems, can they re-align themselves while they are still in motion?
Click to expand...

Can't talk for the rest of the bunch but as far as our own SP-3, SP-4 and SP-5 units go, the following applies:
If power is restored to the gyros while you are in unaccelerated flight (regardless of attitude), the systems will be able to aquire the horizon near instantly. If you are messing around, it will depend exactly how badly. Say you're busy impressing your new girl friend with a few aerobatic stunts without any unaccelerated period of flight inbetween manouvers - in this case no chance. If your doing mild stuff (say normal flight manouvers, I know that is difficult to do in an RV), then the horizon will likely be correct or if showing a minor error, this will correct itself withing seconds to a minute depending how bad it is.
This is perhaps comparable to exceeding your gyros maximum rate of measurement which leaves your horizon in a mess (check the spec sheet of your system to get an idea of the limits, most are around 150-200 degrees, our aerobatic SP-5 takes it to 600 degrees/second).
Different systems have different ways of handling badly treated gyros.
In our case, we give you a function accessible from the keypad 'SHIFT->LEVEL" which sets the gyro derived horizon instantly to that reported by the accelerometers which measure Earth gravity vector - as long as you are in unaccelerated flight, regardless of attitude at that moment, the horizon will be correct from that point onwards.

Rainier
CEO MGL Avionics
 
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