IFD 5 Series & IFD 4 Series Touch Screen GPS/NAV/COM - same database different approach indication?

same database different approach indication?

Printed From: Avidyne
Category: Avidyne General
Forum Name: IFD 5 Series & IFD 4 Series Touch Screen GPS/NAV/COM
Forum Description: Topics on Avidyne's IFD 5 Series and IFD 4 Series Touch Screen GPS/NAV/COM
URL: http://forums.avidyne.com/forum_posts.asp?TID=2574
Printed Date: 15 May 2024 at 9:01am
Software Version: Web Wiz Forums 12.01 - http://www.webwizforums.com

Topic: same database different approach indication?

Posted By: chflyer
Subject: same database different approach indication?
Date Posted: 06 Sep 2023 at 5:40am

Anyone know what conditions would cause a different approach indication on a dual-IFD installation?

I have a IFD540/440 pair. The IFD540 has aviOS 10.2.4 and the IFD440 has 10.2.6. Both have the same (current) navdata coverage and cycle loaded.

Yesterday I did an RNP approach that has only LNAV minimums..... also 2D. On the IFD540 this was shown as GPS LNAV (upper right corner). On the IFD440 this was shown as GPS LNAV+V. Why/how the difference? Is this due to some difference between the OS releases?

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Vince

Replies:

Posted By: AviSteve
Date Posted: 06 Sep 2023 at 3:46pm

First, I would not recommend having different software versions on your IFDs. Nevertheless, it's unlikely that the different software versions were the cause of the discrepancy.

One possibility is that your 440 has the Advisory Glideslope setting ON but the 540 has it OFF. Another possibility is that the 540 GPS just didn't have the vertical accuracy to do +V while the 440 did.

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Steve Lindsley
Avidyne Engineering

Posted By: chflyer
Date Posted: 10 Sep 2023 at 8:25am

Duh.... yeh, you hit it on the head Steve.... Advisory Glideslope settings as mentioned.

Regarding different software versions, I understand the position but sometimes that's the result of Avidyne's own behaviour. I got my IFD440 back from repair with a different AviOS version after spending $2'500 for warranty repair ("LCD screen delamination" above the Avidyne Label in normal operation but not in maintenance mode ..... how Avidyne can claim that I caused this is a mystery to me, it seems anything related to the screen is automatically treated as customer caused). The unit left Avidyne back to me the day before 10.3 was released, so I was looking at an additional $500 to update both units to the same release (10.3).... too much all at once.

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Vince