Autopilot help

asgcpa

En-Route
Joined
Jul 19, 2012
Messages
2,559
Location
Illinois
Display Name

Display name:
CPA
Looking to buy an aircraft. Only AP I am familiar with is STEC 55X.

I am relatively a novice using APs. What should I look for in Autopilots?

Most of planes I am interested in have Auto IIIB in them, if an AP is installed.

I want to have the AP coupled to a Garmin 430 or 530.

How are the Auto IiiBs? Is there a web site that I can learn about different APs? One that cross references features?

Thanks in advance.
 
If you google the various makes you encounter, you often will find a user's manual that can help you with the capabilities of each. The IIIB you mention is a Century unit. I think this is the manual for it: http://www.oldsforgeflyers.com/manuals/archerautopilot.pdf

For flying coupled approaches, you will want something with altitude hold.
 
I should add, I never have found a cross reference chart for them. If you have worked or have access to an avionics shop, you may be able to talk to them about the features and more importantly the issues they have seen with them.
 
I don't know of a single source reference to tell you about all autopilots, but as you encounter them, post here and I bet we can get you hooked-up with useful information.

Nearly every autopilot out there can still be made reliable if you call the right resource.
 
When you find one in a plane, dig through the books for the owners manual and POH supplement. Between the two, you'll be able to figure out the available functions but won't know if they work properly unless you see a demo during a test flight.

Bear in mind that a high percentage of owners don't know squat either, so finding out how they really work can be more challenging than it first appears.

Some units, like the Century 2000, are sneaky-good in that they will do things like coupled approaches without fancy instrumentation (like HSI's) in the panel.
 
The Century/Altimatic III/B/C is what I have the majority of my AP experience with. It is an old AP and as such is not as nice as a 55X. It will track a course or heading, do climbs/descents based on pitch, and will hold altitude if everything works.

That if everything works is a big if. It is possible, but not at all guaranteed. My Aztec had a IIIB and I never got the altitude hold to function right. They said it was impossible to get the altitude chamber rebuilt on the IIIB now. So I just lived with it. The IIIC had runaway trim on both Navajos I flew virtually every flight in altitude hold mode. The 310 (with a straight III) is the best one, and behaves nicely now that I changed out the AI gyro for an overhauled one. The real thing I wish it had was altitude pre-select, and a tone to annunciate being disconnected would be nice.

If you're used to a 55X, it's a downgrade. That said, it is still a functional autopilot and will do the job. I don't want to spend the money to upgrade, but if I was in the market for a new plane, I would consider a C-III to be a negative.
 
You can go to some of the major avionics suppliers,and they will sometimes have a comparison of the units they stock and sell.
 
You can go to some of the major avionics suppliers,and they will sometimes have a comparison of the units they stock and sell.

"That [whatever] you have installed is crap. Here, buy this [much more expensive unit]."
 
Back
Top