Backup Instruments Dynon D2

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captain solo
Posts: 4
Joined: Fri Nov 01, 2013 4:35 pm

Backup Instruments Dynon D2

Post by captain solo » Mon Jan 15, 2018 10:19 pm

http://www.lightaircraftassociation.co. ... rcraft.pdf

Can anybody tell me why the D2 is not on the list of approved units. I have Dynon throughout and would have preferred to keep the same.
Thank you in advance
John
John Bate
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PaulSS
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Re: Backup Instruments Dynon D2

Post by PaulSS » Tue Jan 16, 2018 12:30 pm

The use of other electronic backup instruments must be approved by LAA Engineering, e.g. by means of a modification approval or indication of the approved configuration in the type’s TADS. Note that as additional models are investigated as part of modification approvals, these will be listed here if appropriate.
I'm not deliberately trying to sound facetious but maybe nobody has applied for a modification of that particular instrument. If it does what all the others do then surely it would be permitted.
Paul Simmonds-Short
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AlanR
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Location: Midlands

Re: Backup Instruments Dynon D2

Post by AlanR » Tue Jan 16, 2018 3:17 pm

I don't know but I rather suspect the reason is that the Dynon D2 does not display Indicated Air Speed, only displaying GPS speed.
Alan Radford
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captain solo
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Re: Backup Instruments Dynon D2

Post by captain solo » Tue Jan 16, 2018 3:56 pm

Alan - that makes perfect sense - thank you for replying. Kindest regards, John
John Bate
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Red Comet
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Re: Backup Instruments Dynon D2

Post by Red Comet » Wed Jan 31, 2018 9:50 am

it could be because the Dynon horizon depends on GPS. If the GPS signal is lost, the horizon attitude is lost. (Try switching it on indoors). A standby instrument should be self contained.
Best Wishes etc

Pete
Peter Noonan
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mike newall
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Re: Backup Instruments Dynon D2

Post by mike newall » Fri Feb 02, 2018 3:03 pm

It is because the architecture of the D2 is too similar to the Skyview and there is a perceived risk that a software glitch could disable both the Skyview and the D2.
The Garmin G5 is disimilar to the G3 and therefore satisfies the requirements.
If you want a reasonably priced standby ASI/Alti that is on the list, look at the MGL combined unit. It is available in 2 1/4" and 3 1/8" but requires a backup battery. I have a backup battery system built, not difficult.
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