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Backup for Electrical System Failure

JimMac

Active Member
I just bought an RV-12 with the SkyView 10" display. Does anyone have any comments about what equipment one should have for a backup if the SkyView is inoperable and you find yourself in marginal weather over unfamiliar terrain? I suppose that a hand-held radio, manual compass and a portable GPS would be sufficient to get out of trouble. Any other thoughts?
 
Ipad

I just bought an RV-12 with the SkyView 10" display. Does anyone have any comments about what equipment one should have for a backup if the SkyView is inoperable and you find yourself in marginal weather over unfamiliar terrain? I suppose that a hand-held radio, manual compass and a portable GPS would be sufficient to get out of trouble. Any other thoughts?

I'd go with an iPad Mini (with ATT or Verizon option so that you get the built-in GPS) with Foreflight--self-powered, gives you moving map--just missing the attitude info. Our Skyview once showed us flying 7000 ft BGL (below ground level) for about ten minutes, but the Ipad told us otherwise, until the Skyview slowly got its bearings.
 
Add some 2 1/4" backup instruments

Jim,

You could consider adding some 2 1/4" backup instruments as I have done. I used instruments from UMA. UMA was also willing to silk screen the white and green arcs, ect. on the airspeed indicator.

I installed a vertical card compass as well, but not sure how well that will work out as I have yet to try to swing the compass. First impressions are it will be OK ... but will not know for sure until later in the week (weather permitting).

Plan to also have a notepad as a backup on cross country trips ... plus have Garmin Pilot on my smart phone as a backup for the notepad.

Return from the future: Was not able to swing the PAI 700 vertical card compass to my satisfaction even with compensating balls and Mu-metal. However, an Airpath C2300 compass was able to be successfully swung ... see post 18 in this thread for more info.

Below is a photo of my panel.
DSC01639.JPG


Happy flying,
 
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For the given situation, an Iphone with Foreflight or equivalent would be all that you would need if you are VFR. You could even call ATC on the phone without a backup radio. Might want a headset adapter for the phone.
 
John and all,

Any luck with the standby compass? Anyone install a liquid filled/whisky compass? What is the logic, all be it legit, to not have to have a stand alone none-electric compass?

Thanks for any ideas.

Doug in IL

Jim,

You could consider adding some 2 1/4" backup instruments as I have done. I used instruments from UMA. UMA was also willing to silk screen the white and green arcs, ect. on the airspeed indicator.

I installed a vertical card compass as well, but not sure how well that will work out as I have yet to try to swing the compass. First impressions are it will be OK ... but will not know for sure until later in the week (weather permitting).

Plan to also have a notepad as a backup on cross country trips ... plus have Garmin Pilot on my smart phone as a backup for the notepad.

Below is a photo of my panel.
DSC01639.JPG


Happy flying,
 
Add a Dynon D2 Pocket Panel and a Garmin 660 Aera.

You can wire the D2 and 660 into your electrical system so they are always charged. These two units are simple to install and light.

If you are really worried, toss a handheld radio and extra batteries in your flight bag.
 
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Doug,

To answer your question about the compass .... I don't know yet. I have finally gotten all the bugs out of my RV-12 except for being able to swing the compass. As of now, the north/south is spot on but the east/west is still over 10 degrees off after max adjustment. It is not an electrical issue as the compass is still off with the master switch off.

I've been putting off digging into it because of another mod I'm currently working on. That said, I think I will be able to get it to swing correctly after installing the magnetic balancing balls and mu metal I purchased a few months ago from ACS but have yet to install.

Will try to remember to amend this post with the final outcome.

Return from the future: Was not able to swing the PAI 700 vertical card compass to my satisfaction even with compensating balls and Mu-metal. However, an Airpath C2300 compass was able to be successfully swung ... see post 18 in this thread for more info.

Happy building,
 
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Well said, good advice.

Add a Dynon D2 Pocket Panel and a Garmin 660 Aera.

You can wire the D2 and 660 into your electrical system so they are always charged. These two units are smile to install and light.

If you are really worried, toss a handheld radio and extra batteries in your flight bag.
 
I have the same compass as John-G in the same location, and it's equally inaccurate, although to be fair I haven't gone to great lengths to try to adjust it so far. However, the compass on my iPhone works very well.
 
Well said, good advice.

Thanks Don.

The truth is, these are Day VFR planes. If the pilot can't find his/her way home, or to a near by airport, and land without the EFIS display (which are more reliable than steam gauges), then they need some more training.

(For the record, I have a D1 and 486 for my backup.)
 
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If You Can't Dead Reckon....

Add a Dynon D2 Pocket Panel and a Garmin 660 Aera.

You can wire the D2 and 660 into your electrical system so they are always charged. These two units are simple to install and light.

If you are really worried, toss a handheld radio and extra batteries in your flight bag.

... You shouldn't be up there. Practice. At the same time, the legacy Garmin portables (396, 496) and the the Aera series all have "nearest, direct to, and synthetic panel" functions. Much more readable and reliable than an iPad or iPhone. Bill's suggestions offer enough backup coverage for instrument ( as well as VFR) flight at very minimal cost.
Terry, CFI
RV9A N323TP
 
John,
I enjoy monitoring your build experience and tips and thank you for answering my question. I participated in an AOPA Rusty Pilot session and was reminded that at the tail end of the ARROW acronym is P for Placards and C for Compass Card. I know that we are not required to have a standby non-electric compass and Some of us heavily rely on having multiple electronic sources, I do as well. However, IMHO, having an accurate standby/mechanical compass and knowing how to use it is not the mark of deficient piloting skills, as others suggest, especially when operating out and away from familiar terrain with low risk of complete electronic failure.

John any opinion about installing a in-panel wet compass and it being more conducive to swinging/calibration in our 12's than a card type compass?

Thanks again!
Doug

Doug,

To answer your question about the compass .... I don't know yet. I have finally gotten all the bugs out of my RV-12 except for being able to swing the compass. As of now, the north/south is spot on but the east/west is still over 10 degrees off after max adjustment. It is not an electrical issue as the compass is still off with the master switch off.

I've been putting off digging into it because of another mod I'm currently working on. That said, I think I will be able to get it to swing correctly after installing the magnetic balancing balls and mu metal I purchased a few months ago from ACS but have yet to install.

Will try to remember to amend this post with the final outcome.

Happy building,
 
John,
However, IMHO, having an accurate standby/mechanical compass and knowing how to use it is not the mark of deficient piloting skills, as others suggest, especially when operating out and away from familiar terrain with low risk of complete electronic failure.

John any opinion about installing a in-panel wet compass and it being more conducive to swinging/calibration in our 12's than a card type compass?

Thanks again!
Doug

Doug,

Yes, I have a panel mounted compass backup plan in addition to the phone/tablet I will have in the cockpit. I knew going into it that a panel mounted vertical card compass can be finicky to swing and would be a total c**p shoot. (For that very reason, if you look closely at my panel photo, you will see I did not drill out the holes for the adjustment screws. While attempting to swing the compass I used long 3" brass screws and pushed the compass back to get at the adjusters).

If I can't get the PAI vertical card compass to swing correctly by using the compensating balls and Mu metal previously mentioned, the backup plan is to try to installing a whiskey compass such as a panel mounted Airpath or Falcon. Others have posted here in the forums stating they have had luck with a panel mounted whiskey compass in the RV-12. I would have gone that way to begin with but have to admit, I was drawn in by the "looks cool factor" of the vertical card compass. The last option, albeit an expensive one, is to add a panel mounted digital compass such as the AV-1 or AV-2 from MGL Avionics ... impressive hardware.

I plan on opening up the avionics bay for a mod I'm working on and hope to be doing that within the next few weeks so will play with the balancing balls at that time in the hopes of being able to get the the compass to swing. Guess I can amend this post with the results.

Return from the future: Was not able to swing the PAI 700 vertical card compass to my satisfaction even with compensating balls and Mu-metal. However, an Airpath C2300 compass was able to be successfully swung ... see post #18 in this thread for more info.

Happy building,
 
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Panel mounting PAI 700 compass a failure.

Update: Instillation of Precision Aviation Inc. PAI 700 compass in the RV-12 instrument panel is a failure. However, an Airpath C2300 whiskey compass works just fine …. Go figure!

As mentioned in posts #3,11 & 17 of this thread, I wanted a backup compass in the RV-12 so a Precision Aviation Inc. PAI 700 vertical card compass was installed in the panel. The PAI 700 compass was installed in the upper left corner of the right instrument panel section above a backup altimeter and directly to the right of a backup airspeed indicator located in the upper right of the center panel section (photo can be seen in posts 3). Prior to installing the PAI 700, a check was made to verify the compass displayed the correct readings and had no tight spots … this was accomplished by slowly stepping around in a circle while holding onto the compass and all seemed well. Fortunately, I had the presence of mind not to cut out access holes in the panel for the adjusting screws because I was not sure if the compass could be swung … that proved to be smart.

I and others spent countless hours trying to make the PAI 700 compass work …. sadly to no avail. Initially, the RV-12 was taxied over to the compass rose where the SkyView’s magnetometer was ground calibrated and an attempt was made to swing the PAI 700 compass at that time ... north/south was basically spot on but east/west was WAY off by 15 degrees or so even after the east/west compensator on the compass was maxed out. Not good!

I’ll spare the forum all the troubleshooting methods used, but it did involve purchasing compensation balls which helped immensely but still did not solve the problem. Laying a sheet of Mu-metal across the top of the backup altimeter between the compass and the altimeter had the biggest affect and there was a point in time when I thought the compass would be usable using Mu-metal in conjunction with the compensating balls … but the compass began giving flaky non-repeatable readings, so decided it was time to throw the towel in.

Photo of the compensation balls attached onto the back of the PAI 700 vertical card compass:
https://4.bp.blogspot.com/-RM1weCkryus/WXQIvuZ6fUI/AAAAAAAAMt0/_Zl7aiISgHc3omelHtXzxZ_g5VdFESgcQCLcBGAs/s1600/DSC02701.JPG

Photo of the Mu-metal that was installed under the PAI 700 vertical card compass.
https://2.bp.blogspot.com/-nG2CxA-Mxs0/WXQNAAGBC_I/AAAAAAAAMuY/BlwDm_s9lRwO9S695y0XRzfHojeb2JPJQCLcBGAs/s1600/DSC02769.JPG

Decided to yank out the PAI 700 and replace it with an AirPath C2300 whiskey compass. Had much better luck with the C2300 which was able to be successfully swung … however, discovered it also required the sheet of Mu-metal installed across the top of the backup altimeter. Even with the Mu-metal in place the east/west compensator is maxed out … but most of the readings are within a couple of degrees now with the worst being 4 degrees off. So the Airpath C2300 compass is quite usable for a backup ... but nowhere near the “cool factor” of the PAI 700. In this case, it’s function over form.

Photo of the Airpath C2300 whiskey compass along with the Mu-metal which was necessary to allow the compass to be swung.
https://4.bp.blogspot.com/-iBCYGr7LdtI/WXQOvOUH_MI/AAAAAAAAMuk/iJVRXRZipx0pdeqsRS65xdmhMfltK9ajwCLcBGAs/s1600/DSC02783.JPG

New look of the DOG Aviation RV-12 front panel ... lost is the coolness of the vertical card compass .... gained is the functionality of the Pathway C2300 whiskey compass.
https://1.bp.blogspot.com/-kWDmWHdiOZM/WXQQbMsjAyI/AAAAAAAAMuw/zILXC-zLUoAyzkVEGSh4qJgLaGIcZaQ5QCLcBGAs/s1600/DSC02781.JPG
 
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iPad 2 has pressure sensor

I'd go with an iPad Mini ...with Foreflight--self-powered, gives you moving map--just missing the attitude info.
My iPad Air2 has a built in pressure sensor set to 29.92 so Foreflight displays either GPS altitude or Pressure altitude. I don't know about the mini...
 
Update: Instillation of Precision Aviation Inc. PAI 700 compass in the RV-12 instrument panel is a failure. However, an Airpath C2300 whiskey compass works just fine …. Go figure!

As mentioned in posts #3,11 & 17 of this thread, I wanted a backup compass in the RV-12 so a Precision Aviation Inc. PAI 700 vertical card compass was installed in the panel. The PAI 700 compass was installed in the upper left corner of the right instrument panel section above a backup altimeter and directly to the right of a backup airspeed indicator located in the upper right of the center panel section (photo can be seen in posts 3). Prior to installing the PAI 700, a check was made to verify the compass displayed the correct readings and had no tight spots … this was accomplished by slowly stepping around in a circle while holding onto the compass and all seemed well. Fortunately, I had the presence of mind not to cut out access holes in the panel for the adjusting screws because I was not sure if the compass could be swung … that proved to be smart.

I and others spent countless hours trying to make the PAI 700 compass work …. sadly to no avail. Initially, the RV-12 was taxied over to the compass rose where the SkyView’s magnetometer was ground calibrated and an attempt was made to swing the PAI 700 compass at that time ... north/south was basically spot on but east/west was WAY off by 15 degrees or so even after the east/west compensator on the compass was maxed out. Not good!

I’ll spare the forum all the troubleshooting methods used, but it did involve purchasing compensation balls which helped immensely but still did not solve the problem. Laying a sheet of Mu-metal across the top of the backup altimeter between the compass and the altimeter had the biggest affect and there was a point in time when I thought the compass would be usable using Mu-metal in conjunction with the compensating balls … but the compass began giving flaky non-repeatable readings, so decided it was time to throw the towel in.

Photo of the compensation balls attached onto the back of the PAI 700 vertical card compass:
https://4.bp.blogspot.com/-RM1weCkryus/WXQIvuZ6fUI/AAAAAAAAMt0/_Zl7aiISgHc3omelHtXzxZ_g5VdFESgcQCLcBGAs/s1600/DSC02701.JPG

Photo of the Mu-metal that was installed under the PAI 700 vertical card compass.
https://2.bp.blogspot.com/-nG2CxA-Mxs0/WXQNAAGBC_I/AAAAAAAAMuY/BlwDm_s9lRwO9S695y0XRzfHojeb2JPJQCLcBGAs/s1600/DSC02769.JPG

Decided to yank out the PAI 700 and replace it with an AirPath C2300 whiskey compass. Had much better luck with the C2300 which was able to be successfully swung … however, discovered it also required the sheet of Mu-metal installed across the top of the backup altimeter. Even with the Mu-metal in place the east/west compensator is maxed out … but most of the readings are within a couple of degrees now with the worst being 4 degrees off. So the Airpath C2300 compass is quite usable for a backup ... but nowhere near the “cool factor” of the PAI 700. In this case, it’s function over form.

Photo of the Airpath C2300 whiskey compass along with the Mu-metal which was necessary to allow the compass to be swung.
https://4.bp.blogspot.com/-iBCYGr7LdtI/WXQOvOUH_MI/AAAAAAAAMuk/iJVRXRZipx0pdeqsRS65xdmhMfltK9ajwCLcBGAs/s1600/DSC02783.JPG

New look of the DOG Aviation RV-12 front panel ... lost is the coolness of the vertical card compass .... gained is the functionality of the Pathway C2300 whiskey compass.
https://1.bp.blogspot.com/-kWDmWHdiOZM/WXQQbMsjAyI/AAAAAAAAMuw/zILXC-zLUoAyzkVEGSh4qJgLaGIcZaQ5QCLcBGAs/s1600/DSC02781.JPG
I guess there's a couple around that believe in having a nonelectric backup, thanks John!
 
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