DFC90 AP not accurate after installation of dual I |
Post Reply |
Author | |
pat@werigi.com
Newbie Joined: 31 May 2013 Location: KPTK Status: Offline Points: 30 |
Post Options
Thanks(0)
Posted: 02 Aug 2015 at 8:44pm |
2007 Cirrus W/Avidyne MFD,PFD & DFC90 dual IFD440 After the installation of dual IFD440's my DFC90 performs like the Stec 55X that I swapped it out for. Sot several RNAV approaches today and my AP "hunted" for the final approach course. My AP was super accurate prior to the install. Any thoughts? Thanks Pat |
|
AviSimpson
Senior Member Joined: 31 Mar 2015 Location: Lincoln, MA Status: Offline Points: 765 |
Post Options
Thanks(0)
|
This is odd. There shouldn't have been a change going from the 430 to 440 in regards to autopilot control. Was there any changes to the PFD? Are you getting "Servo Limit" CAS messages on you PFD?
|
|
Simpson Bennett
Avidyne Corporation Product Manager |
|
bdevault
Newbie Joined: 07 Sep 2015 Location: The Woodlands, Status: Offline Points: 5 |
Post Options
Thanks(0)
|
Wow, I thought I was the first one to have *that* problem. I bet we aren't the only ones who have it though given that DFC90 Cirri with Entegra and 440s can't be a rare combo.
LPV approaches couple the DFC90 in "NAV APPR" mode just like an ILS, track the GS perfectly but then proceed to fly the last 1000' or so down to the DH very sloppily on lateral guidance just like the S-TEC it replaced. The DFC 90 also continuously performs S-turns when tracking garden-variety VOR signals and can't ever quite seem to find a stable course. Here's the weird thing: the DFC 90 *still* flies ILS's perfectly, indeed so well you can leave it engaged until you're over the numbers (that is, when it will even tune the ILS signal at all, which is another issue I'm fighting with my two new 440's, in which ILS/LOC signal acquisition seems occur at random, but that's a whole other rant...). I called support when I noticed this and they seem as confused as I am about the whole thing. I've now sent them my logs. |
|
Bryan
|
|
AviJake
Admin Group Joined: 26 Mar 2009 Location: Lincoln MA Status: Offline Points: 2815 |
Post Options
Thanks(0)
|
Looking forward to seeing those logs. I've personally flown hundreds of GPS approaches with dual IFD and DFC90 configuration to DH and lower and have never seen this. Nor do we have any other reports of this kind of behavior.
Would like to hear the other rant too since I've also never had the slightest issue with tuning of the ILS signal. In fact, I can't remember the last time I've manually tuned a localizer frequency. |
|
Steve Jacobson
sjacobson@avidyne.com |
|
AviJake
Admin Group Joined: 26 Mar 2009 Location: Lincoln MA Status: Offline Points: 2815 |
Post Options
Thanks(0)
|
Flew a coupled RNAV approach down to about 30' AGL in VFR conditions today and the airplane never budged off of dead center glideslope and glidepath.
Looking forward to seeing your logs. |
|
Steve Jacobson
sjacobson@avidyne.com |
|
Post Reply | |
Tweet
|
Forum Jump | Forum Permissions You cannot post new topics in this forum You cannot reply to topics in this forum You cannot delete your posts in this forum You cannot edit your posts in this forum You cannot create polls in this forum You cannot vote in polls in this forum |