I would like Roll Steering…..I have the KCS55 system with KAP 150 and a 430W…..does anyone have any experience of the DAC GDC31?
I have flown with the DAC and your autopilot and GPS and it does a very nice job. I would highly recommend it. You should also consider an Aspen as a viable alternative if you want the additional function it offers.
Yes, with G1000/GFC700. Ok, it doesn’t use the emulated heading bug kludge a roll steering converter uses.
Well then, you have integrated roll steering, why would you deny the heading bug kludge to us poor folks. Sounds a little aristocratic, let them eat cake.
To not be hypocritical, make sure you never use Nav mode enroute on your G1000/GFC700 when using the GPS for navigation or on an RNAV approach using APR mode, we wouldn’t want you to be using true roll steering.
So that means in Europe it’s probably more like 5000$. If you suffer from not knowing where to spend your money, then why not install a roll steering converter. But even in this case I’d probably put that 5000$ into the bank, so at the current interest rates in about 150 years you’ll be able to buy a proper autopilot that has envelope protection, which is IMO a lot more useful than roll steering.
I guess your right, why spend $5000 when you can spend $100,000 for a proper autopilot. 
My own plane has a Century II autopilot with the associated radio coupler, no roll steering. I’m not missing it.
I’ve also flown with a G1000/GFC700, so I know the difference.
why would you deny the heading bug kludge to us poor folks
I’m not denying anything to anyone, I just think it’s not worth it.
Incidentally, NCYankee, did you pay for your roll steering converter, and how much?
Just for the work/install or does that include the GTN650? If the latter, you must work for free, if the former, it’s on the expensive side…
That is including the GTN650. I don’t work for free as I do this for a living. Do note it is in Euro not USD
Do note it is in Euro not USD
Thanks for pointing this out, you’re right, that’s what I paid approximately in the end. Although I did have quotes for “at least 22k€”.
Incidentally, NCYankee, did you pay for your roll steering converter, and how much?
Yes, but I am a bad example. I owned an avionics shop at the time and I installed it right after Stec first came up with the concept for the roll steering to heading error adapter. This was in the mid 1990’s, sometime after 1996. The initial price was $1200 list price for the hardware (now up to $2,200 ish). To promote the concept, they had an introductory half price sale. That made it $600. With my 40% dealer discount, mine only cost me $360 and I did not charge myself for the labor. Subsequently the price went to $1200 and typical labor for installation was 10 hours. Back then, our shop rate was $65/hour so we charged in the vicinity of $650 labor plus the hardware for 20% discount, or just under $1000, total fly away cost to the customer around $1,600. With today’s prices, labor rates vary between $85 and $100 per hour, so I would expect it could be installed for $3,000 +/-. A reasonable auto pilot such as an Stec 55X would run close to $30,000 installed and comes with roll steering built in. The KFC 225 can be installed for somewhere in the $40,000 area and also includes roll steering as standard. To the Stec 55X, you could add the Avidyne autopilot if the STC supported the aircraft type and get the advanced features of the GFC700 but also need to add an Aspen PFD with a total upgrade cost of an additional $28,000, The DAC GDC31 can be purchased for under $1800 today from several internet outlets.
No doubt a modern autopilot is more expensive, but it adds useful features, such as envelope protection, which I consider a safety feature.
On the other hand, I still fail to see the benefit of roll steering. Quite obviously, roll steering is only applicable to turns in a procedural type of operation (i.e. on a GPS flightplan). It is not applicable to radar vectors. And it is not applicable to straight and level flight, so it doesn’t help the “direct to destination” bit.
The only procedural type of operation I regularly fly is an SID. But with these old autopilots, you need to babysit the autopilot in climb anyway to prevent it from stalling the plane. Furthermore, SIDs are often either very simple (such as straight ahead to MRVA), or very complex with half the legs having leg types the 650 (or about any GPS) does not support and thus cannot sequence anyway.
So even if roll steering may only be 3000$, I still don’t see the value it adds.
Interestingly, when I ordered the 650 upgrade, the avionics shop didn’t ask me whether I wanted roll steering – so either they’re completely overloaded, or it simply isn’t on the radar.
That is a misconception in my opinion, yes roll steering will handle curved paths, but the vast majority of the time it is used on straight legs, even here in the US. I use roll steering all the time on direct to routes. New clearance direct to ABCDE, enter ABCDE, direct-to, instant turn to on course with wind corrected track. No need to set the HSI OBS pointer, although it is good form to do so. Straight legs with turns, if you are occupied with something, it will make the turn. Peter has sent me some fairly long IFR routes he has used on Holiday travel, many airways, many turns, many waypoints. Once programmed, it is child’s play with roll steering. We also have airspace to avoid when VFR such as Class B and C areas, and military areas here in the US that it is nice to set a few user waypoints up to circumnavigate to avoid an accidental penetration and resulting pilot deviation.
RNAV procedures, particularly approaches using a T design, it leads and handles the turn anticipation. Here in the US, the PT or hold can be flown as can the teardrop turns that seem to be more often used outside the US than inside. We tend to have more DME arcs leading to a localizer when radar services are not available, it flies those just fine down the center of the arc.
What I have little use for is the blue button, I have managed to fly more than 47 years without ever having a need for it. I did fly over a hundred hours in a SR22TN with G1000 Perspective that had the blue button and envelope protection. Other than to see what it would do in an unusual attitude as a test, never used or needed it. I guess it might have helped if Air France 447 had it.
Peter has sent me some fairly long IFR routes he has used on Holiday travel, many airways, many turns, many waypoints.
Yes the flight plan has it. But I cannot remember ever having flown the planned route. In fact, about 5 min into the flight, I’d have to think hard in case of a comms failure on how to get back to the planned route. So if you ever want to fly your planned route, you’ll have to squawk 7600 (and fill out some forms after landing).
No need to set the HSI OBS pointer
No good idea IMO, I’d get confused pretty quickly.
What I have little use for is the blue button
I’m not talking about the blue button. I’m talking about the autopilot not allowing the airspeed to deteriorate to the stall speed. It doesn’t need all that much flying to experience this, certainly not 47 years. Last time for me was on the way to the euroga meeting in Mali Losinj, hadn’t I intervened, the AP would have happily stalled the aircraft.
What I have little use for is the blue button, I have managed to fly more than 47 years without ever having a need for it.
This is hopefully true for all safety features suchs as seatbelts, CAPS, air bags etc. as well.
