DigiFlight II VSGV

[jrouault]

Received new AFS A/P head from Trutrak and my problems are now gone... things work like they should. Although, I am a little perturbed that the AFS autopilot can no longer be driven directly from the GNS430W... The EFIS has to always be in the picture. So, if I have an EFIS failure, I cannot use the GNS430W to directly drive the AFS autopilot.

[akschu]

Can someone confirm this? My autopilot is to some degree the backup for the EFIS, so this is very undesirable in my setup.

Also, what is to be gained by using the AFS version of the software?

schu

[sneedrv-6]

I have a switch on my panel that takes the efis out of the picture and connects the 430w directly to the AP. Even with a dual efis system if you lost the PFD you can't shoot a GPS approach with the MFD, in this case I would want to have the 430w control the AP while shooting an approach while I watch the MFD for attitude, altitude, and speed. I guess there is a chance this switch will not work when I get my AP back but I would think it would still work. I know Rob has the ability to allow the efis to just pass the data from the 430 to the ap, because this is what he does once you are on the approach, at that point the data is just flowing from the 430w to the AP (unless something big has changed)...

Jason

[jrouault]

Originally Posted by sneedrv-6

I have a switch on my panel that takes the efis out of the picture and connects the 430w directly to the AP. Even with a dual efis system if you lost the PFD you can't shoot a GPS approach with the MFD, in this case I would want to have the 430w control the AP while shooting an approach while I watch the MFD for attitude, altitude, and speed. I guess there is a chance this switch will not work when I get my AP back but I would think it would still work. I know Rob has the ability to allow the efis to just pass the data from the 430 to the ap, because this is what he does once you are on the approach, at that point the data is just flowing from the 430w to the AP (unless something big has changed)...

Jason

If we are talking about the AFS autopilot for Trutrak, you cannot have the GNS430W drive it directly without the EFIS unless you are already in approach mode. I have raised this issue with Trutrak and they say it was designed that way because it is being sold as an integration with the AFS EFIS and not as a stand-alone system. I personally think that is a bunch of hogwash. The autopilot should be able to get lateral navigation guidance directly from the GPS without the EFIS if one so desires. My current panel is already setup with a source select switch for the A/P that I used with my II VSGV system prior to having it upgraded to the AFS system (now it is kinda useless) I would think this would only require a software change to support this capability, but Trutrak seems unwilling to address my concerns.

[breister]

Originally Posted by jrouault

If we are talking about the AFS autopilot for Trutrak, you cannot have the GNS430W drive it directly without the EFIS unless you are already in approach mode. I have raised this issue with Trutrak and they say it was designed that way because it is being sold as an integration with the AFS EFIS and not as a stand-alone system. I personally think that is a bunch of hogwash. The autopilot should be able to get lateral navigation guidance directly from the GPS without the EFIS if one so desires. My current panel is already setup with a source select switch for the A/P that I used with my II VSGV system prior to having it upgraded to the AFS system (now it is kinda useless) I would think this would only require a software change to support this capability, but Trutrak seems unwilling to address my concerns.

In another post TT said that you still have the ability to connect the NMEA/Serial output of the GPS directly to the AFS autopilot. If this works the same way as the "normal" II APs, this will give you lateral guidance if you REMOVE the AFS source data stream (either through failure, powering it down, or wiring in a shutoff switch between the AFS and the AP). It will still require you to press the MODE button (or equivalent on the AFS version) to slave to the GPS steering, but that should be all.

I keep telling TT they should market this as a feature, and also have the MODE button soft-switch to the NMEA source. Still, it's nice to know it is there as a backup.

[flyvans.com]

interesting...
thank you jason for posting this!

now that the backup magnetometer will be out plus the apparent incapacity of backup gps nav i wonder wheter paying 250$ for a get-some-loose-some proposition is worth it? i know i will have to do it to get the full afs integration that i'm counting on... but i always regarded the operational/hardware independence (but tight integration) of the autopilot and efis as a strong selling point vs the all-in-one dynon and bma setups (which have other advantages such as price and software capability).
now, this makes this selling point obsolete!

confirm, without the efis source (but direct hookup of a gps to the trutrak) the afs version is no longer able to fly a simple track and altitude including vs?
heck, why would it even need it's own gps hookup anyway?!

that would be big-time lame and get me seriously p...ed!
no wonder nobody knew since obviously documentation and software versioning on behalf of trutrak is less than transparent!

always had great customer service by luke @ tt and believe it's a wonderful product and a great company with an excellent reputation.
but unnecessary limitations like these are missing the sign of the times! also i'd rather have the capability of downloading the latest firmware and installing it myself just like every other device does these days (heck even flashing pc bios is practically dummy-proof nowadays).
this is even more important when one lives in europe and shipping is always an extra hassle!

my 20cts,

rgds, bernie

[jrouault]

Originally Posted by flyvans.com

interesting...
thank you jason for posting this!

now that the backup magnetometer will be out plus the apparent incapacity of backup gps nav i wonder wheter paying 250$ for a get-some-loose-some proposition is worth it? i know i will have to do it to get the full afs integration that i'm counting on... but i always regarded the operational/hardware independence (but tight integration) of the autopilot and efis as a strong selling point vs the all-in-one dynon and bma setups (which have other advantages such as price and software capability).
now, this makes this selling point obsolete!

confirm, without the efis source (but direct hookup of a gps to the trutrak) the afs version is no longer able to fly a simple track and altitude including vs?
heck, why would it even need it's own gps hookup anyway?!

that would be big-time lame and get me seriously p...ed!
no wonder nobody knew since obviously documentation and software versioning on behalf of trutrak is less than transparent!

always had great customer service by luke @ tt and believe it's a wonderful product and a great company with an excellent reputation.
but unnecessary limitations like these are missing the sign of the times! also i'd rather have the capability of downloading the latest firmware and installing it myself just like every other device does these days (heck even flashing pc bios is practically dummy-proof nowadays).
this is even more important when one lives in europe and shipping is always an extra hassle!

my 20cts,

rgds, bernie

Yes, I am kinda regretting I did the upgrade to the AFS pilot. You get some nice integrated functionality with the AFS EFIS, but you also lose some basic functionality. At this point I am not sure the trade-off is worth it. Maybe I will change my mind after flying the integrated AFS setup for a while.

See thread in the Trutrak forum: http://trutrakap.com/forum/showthread.php?p=571#post571

[sneedrv-6]

I have not done much research on this issue, I am concentrating on trying to get everything working, spent a ton of $ to have an IFR bird able to shoot GPS approaches more than a year ago and still send parts back and forth to companies. I do know that Lucas told me I do not gain anything by upgrading to the AFS pilot EXCEPT I have to 2-3 more buttons to get the AP in gpss steering and altitude, but Lucas also thought I should have mag. calibration in my unit which it now appears from reading the forum I should not have it. One of the things I hate about these experimental companies is that they make a unit and the documentation, then years go by and the unit is so different the user guide does not even go with the unit. I will say that Rob and AFS is better than the norm on this topic.

When I designed my panel I thought if I lost the PFD I could still shoot an approach with the MFD. After the install I found out this is not true (unless I just lost the display and the unit was still working.) I found this out while flying and my PFD decided to stop working (bad power supply). At any rate I actually split the nav signal coming from the 430w and sent it to both AFS screens, I use to be able to pull the fuse on my PFD and still hand fly an ILS off the MFD but I think Rob said this will not work with the new software (I need to test this). At any rate, I REALLY do not like the thought of flying IMC without the AP, in fact, the only way I would do it is if the AP crapped out with in IMC and I would get direct vectors to VFR conditions. I would encourage everyone to fail your PFD and then assume you were in IMC and have to shoot an approach to Minimums, what would you do?

[breister]

Again, it appears some people are posting potentially incorrect information here.

This conversation would probably be better held on the TruTrak forum, which they monitor more frequently.

My understanding is that the AFS version still has an auxiliary GPS input, so if this is hooked directly to the GPS and the EFIS fails the AP will still have direct input from the GPS (Serial, lateral guidance only).

The "lack" of the backup magnetometer is not a "loss," it was an upgrade. Too many pilots had challenges ever getting the magnetometer sufficiently calibrated in the panel environment to make it consistently reliable, so they changed the "emergency mode" (no GPS signal) to "Gyro Assisted Heading Hold." If you have your hand held (or primary) GPS hooked up to the Serial connection, this mode should never be engaged even if your EFIS quits.

Likewise, I do not fully understand the AFS EFIS but it is my understanding that when hooked to the AP you gain the ability to couple to Nav and ILS as well as GPS approaches, and also to use the EFIS heading set and altitude set bugs. These features would require the TT Sorcerer without the EFIS, an additional $4250 price difference. Maybe I'm silly, but that sounds like a doubling of the utility using the same autopilot, features well worth having.

Furthermore, it seems that there is some uncertainty as to whether you can use a DPDT switch between the AP ARINC input lines and the EFIS / GNS 430W ARINC Output lines, allowing you select the GPS as your data source. For that you will require either confirmation from TT or experimentation - the biggest holdup would be if the AFS requires different output settings from the 430W than the TT can "read." But, if it DOES work then my expectation would be that it will then work identically to a II VSGV coupled directly to a 430/430W.

My point is, before you all go boo-hooing about what you think you don't have, why not find out the facts?

[TrutrakTech]

Let me see if I can put out some of these fires.

First, software updates in the field. Yes, we wish we had done this initially. However, the Digiflight II series and Sorcerer series autopilot core hardwares were designed 5-6 years ago. At that time we didn't think it would be necessary or prudent to add that capability. If you're at all familiar with our EFIS, you'll notice we rectified that previous mistake. Future products will be able to have the software updated in the field.

COMPLETELY redesigning the hardware in 90% of our product line is not an option as redesigning the hardware would also require an entire rewrite of the software. The code is developed to work with the hardware currently in the unit.

Second, the AFS Pilot is designed for full integration with the AFS EFIS, NOT a 430W. In the event of an EFIS failure, you still retain the basic AP modes, i.e. track mode, alt hold, and vertical speed select. There are only three buttons on the unit and a lot of features to get done with those buttons. Button layering with varying degrees of time delays is not something we want to include in the unit as it will GREATLY decrease the ease of use. It is still important to add an RS232 connection to the AP. That gives the track mode its info so that the bank angle backup mode will never even be seen.

Third, removal of the magnetometer. Bill is correct. We removed the magnetometer because we found it to be unreliable in too many uncontrollable conditions. The bank angle mode gives VERY reliable performance for a backup mode. It's much more stable at keeping you on course than the magnetic backup mode was. While we aren't retrofitting units that have the magnetometer free of charge anymore, we are no longer using it in DII units.

jrouault: I'll be happy to refund your $250 if you want to send the AFS Pilot back to us and I'll send you a DII VSGV.

As I said on our forum, I will bring this subject up with the engineer when I talk to him next week. I will gladly post up with any info I gather from that conversation.

I hope I've answered at least SOME of the questions here. One thing I must mention is that I've never been dishonest about the features, functions, and capabilities of either unit. I've been up front with everyone who has inquired.

If anyone would like to discuss anything with me one on one, please feel free to PM me. Thanks!