Forums for AFS?

I'm trying to figure out if there's a discussion forum for Advanced Flight Systems' EFIS. There are groups for GRT, Dynon, MGL and BMA but I can't find one for AFS. Anyone have a link?

-Rick

rickmellor said:

I'm trying to figure out if there's a discussion forum for Advanced Flight Systems' EFIS. There are groups for GRT, Dynon, MGL and BMA but I can't find one for AFS. Anyone have a link?

-Rick

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Why don't you start one ?
Do it before the manufacturer does and you'll have an open forum that is not under control of the manufacturer. Can be a good or bad thing. Depends.

It's what happened to us - one of our customers sent us a mail one day saying "guess what - you have a forum now. But it's not yours...".
The MGL forum grew rapidly and is quite active and has proven valuable both for our customers and for us. I'm sure you'd be able to do similar with AFS. Looks like a very nice system. Deserves a good forum.

Rainier
CEO MGL Avionics

It does need a good forum with an active community. I haven't yet decided which EFIS I'll be installing and I wouldn't have any interest in maintaining the thing if I go a different direction. AFS is on my short list so maybe there's a chance I'd kick it off.

Forums can be good and bad for the company but I think they're always good for the customer. My 'emotionally favorite' EFIS is one that I'd never buy because of what I've seen its customers go through via the forum. This is bad for the company but for me the customer I've been spared a potentially horrific experience. On the flip side, I need to be careful not to think too highly of other vendors who either don't have a forum or who censor their forums. An absence of information shouldn't impart confidence. Finally, negative forum posts should be taken with a grain of salt. Few people take the time to post good news and those who have issues and contact the company directly may have been completely satisifed with the result. You've got to follow the group for a long time and understand the trends before drawing conclusions.

I think the best approach is to have an open forum that is hosted by the company (official forums). Companies shouldn't censor the posts but should monitor / participate heavily in the discussion (e.g., Dynon, BMA). I haven't followed the MGL forum but I'm sure you guys are quite active there as well.

-Rick

rickmellor said:

I think the best approach is to have an open forum that is hosted by the company (official forums). Companies shouldn't censor the posts but should monitor / participate heavily in the discussion (e.g., Dynon, BMA). I haven't followed the MGL forum but I'm sure you guys are quite active there as well.
-Rick

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Yes we are quite active there. It's become our sounding board for ideas and of course we answer questions or give advice where it is asked for.
There have not been any bad posts (yet) and we hope there will not be a reason for that ever. If somebody is not happy, we'd rather hear about it from him/her direct or if need be via a dedicated forum. Then at least we can respond in whatever way is needed which is quite fair to us.
That is far better than somebody not happy telling everybody but not telling us - then we don't have a chance to make amends or do anything until it is way too late.

It's a bit tricky to maintain that kind of close relationship with your customers in partular if you have grown to have perhaps 10.000 of them and you are a small company - but forums are an excellent way and we appreciate their existence very much indeed.

We find the forum is very helpful in particular as many knowledgable customers participate and often can give a newbee great advice and help before we even get to see the post.

Rainier
CEO MGL Avionics

MGL Avionics!

I apologise, but I do not know MGL, but I am almost ready to buy my avionics and I would like to know how to contact your company for information. Can you give me your web address?

Thanks,

Carl Nank

[email protected]

We are perhaps one of the largest makers of Electronic Flight instrumentation systems but are not too well known in the U.S. homebuilders section - but this is changing very rapidly. Our traditional markets are ultralights, homebuilts and factory built NTCA and special projects (many are certified, like Russian Blimps fitted with Ultra panels) but this has been changing dramatically in the past year as we are "discovered"

Our website is www.MGLAvionics.co.za, a further nice site is www.Stratomaster.com/Enigma (just dedicated to the Enigma). Our U.S. distribution has been with SportFlyingShop in California for many years. They have been very good.
A quick search for "MGL Avionics" in Google will lead to much info...

Rainier
CEO MGL Avionics

cbnank said:

MGL Avionics!

I apologise, but I do not know MGL, but I am almost ready to buy my avionics and I would like to know how to contact your company for information. Can you give me your web address?

Thanks,

Carl Nank

[email protected]

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MGL

http://www.mglavionics.co.za/index.html

http://www.stratomaster.com/Enigma/

cbnank said:

snip.... but I do not know MGL, but I am almost ready to buy my avionics and I would like to know how to contact ...snip

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About an inch to the left of your post .



http://www.sportflyingshop.com/Instr/Stratomaster/Enigma/RV/rv.html

AFS Forums

Our Forum is in the works and should be up and running in the next four weeks. We have been waiting until we move into our new facility in June.

Our new facility will enable us to better serve our customer?s needs and enable us to dramatically increase production of our avionics product line. Our new 7,500 sq-ft facility is located at 320 Redwood St. Canby, OR 97013

Rob Hickman
Advanced Flight Systems Inc.

N401RH said:

Our new facility will enable us to better serve our customer?s needs and enable us to dramatically increase production of our avionics product line. Our new 7,500 sq-ft facility is......

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This sounds like a good indication of the health of the company.

That 3500 sure is sweet.

Good job, Rob.

Mike

I have dealt with ACS a lot over the years, have installed several of their engine systems and will install their 3500 in my new 7. They have been very strong in customer service and I beleive their system doesn't rely on the pitot for the horizon. Larry

LARCO said:

I beleive their system doesn't rely on the pitot for the horizon. Larry

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This opens a can of worms. Let me throw a bit of light on the subject if I may. I have now designed 6 generations of AHRS sensing systems so I have learned a little about it.

The correct term is "aiding". What it means is to use sensor measurements other than gyro "rate of turn" and acceleration measurements to figure out how you are related to the Earth surface level. What we are trying to do in particular is to somehow remove the apparent errors caused by accleration on the horizon view derived from the accelerometers to get a vector on Earths gravity. We would like to know this in cases other than straight and level flight so we can correct for measurement errors from the gyros - all gyros are flawed, no matter how much money you spend on them, just the rate of error goes down as the cost goes up, but it never gets to zero.
OK, in order to do this we need to measure acceleration by means of an independent way. The two obvious means are using a GPS receiver and/or airspeed compensated for temperature and altitude (i.e. TAS).
Using this and a bit of arcane mathematics, we can get a corrective value, at least "sort of" - we have to assume a few things. As long as we assume correct, it works. If we assume incorrect, the aiding makes matters worse.

Best example: Mount an aided and unaided system in a car. The aided system will fall over horribly as it will assume banking and other things the car is not going to do. The unaided system will do better in this case.

Put both in an aircraft and fly "nicely". The aided system will outperform the unaided in this case - but start doing unusual things (which may be something as little as a badly unbalanced turn) and the aided system may perform worse as it is assuming wrong.

Aiding is a good thing but must in all cases be done very, very carefully or else the result will not be to expectations. One can distinguish between "weakly" aided and "strongly" aided systems. Usualy, the worse the gyros, the more strongly the aiding needs to be done.

Every maker of AHRS wields his own "black magic" here - based on experience and to some extent the platform (i.e. your aircraft) dynamics. An AHRS designed for a 747 will have a very different set of parameters compared to something in your RV or even a helicopter.

Some AHRS units can be setup to perform in various environments, optimising performance in these cases, others are fixed and yet others will "change themselves" according to what is happening.

Apart from the obvious, very involved theoretical work, practical flight testing is one of the most powerful ways to judge how the many algorithms work together in real time.

Current AHRS technology in the "low cost" region has made some amazing progress in the last two years as we all are starting to squeeze performance out of low cost gyros that was deemed close to impossible just a short time ago. The final word on this has not been spoken yet - even better systems at even lower prices are just around the corner !

Best overall value for the buck in my opinion goes currently to a "weakly aided" system using gyros in the low to medium cost range. That is stuff that can now match and exceed TSO-C4c requirements and that you can start trusting. Such a system will still work as a good unaided system if it does not receive aiding.

Rainier
CEO MGL Avionics

Cool!

Thanks for the education Rainier! That's the kind of description that makes all the hours of trolling these forums worthwhile.

Rob, thank you for giving a heads-up on the forums. I can't wait to learn how your customers are enjoying your new EFIS.

-Rick

Rainier Lamers said:

...
The correct term is "aiding". What it means is to use sensor measurements other than gyro "rate of turn" and acceleration measurements to figure out how you are related to the Earth surface level. What we are trying to do in particular is to somehow remove the apparent errors caused by accleration on the horizon view derived from the accelerometers to get a vector on Earths gravity.
...

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Is this because you are using three angular rate sensors and not a mechanical gimbal kind of thing? I'm just curious to how it actually work.

SvingenB said:

Is this because you are using three angular rate sensors and not a mechanical gimbal kind of thing? I'm just curious to how it actually work.

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Yes, this is particular to a "strapdown" system using three (or more in rare cases) rate gyros.
Most systems use some means of using earths gravity acceleration. The vaccum driven gyro and electrical gyro use a "pendoulous" unit to errect the horizon. AHRS strapdown systems use a set of three (sometimes two) accelerometers to do this.
In principle, the idea is to allow the earth gravity to, very slowly, cause the horizon display to be level. If you would fly in a continous banked circle, your horizon will eventually show level. How long this takes is determined by the manufacturer. The better the system the longer it takes. Very good systems costing $100.000 use heavy, very well balanced gyros spinning at high speed on bearings that are beyond perfection in a vaccuum to reduce any form of friction. This is the kind of thing still prefered on Submarines.
Very expensive strapdown systems use laser gyros where relativistic light effects using monochromatic light sources are used to create an interference pattern which can be interpreted as accurate source for rotation. These are not yet found in our kind of budgets and belong to airliners and the military.

Anyway, regardless of what you have as gyros - you need something to tell you the general direction of the planet as a starting point. Very good gyro systems can measure the rotation of the Earth and use this as indirect means (but this takes a while).
So we use some form of pendulum. In our "poor mans" AHRS systems, we use a set of accelerometers. These give a good measure of this in straight and level or otherwise "unaccelerated" flight.

In many systems the "correction" applied by the accelerometers is continous but weak so your horizon will eventualy show level in a banked turn (and then show a bank if you rotate out of the turn).

The basic idea behind common IFR manouvers is to make procedure rate one turns, 90 degrees and 180 degrees before you have a straight segment (where your AHRS can correct for any errors that have crept in during the turn).

The low cost systems (like our SP-4) are getting quite good but use several additional methods thanks to powerfull processors and use the accelerometers very differently, continously evaluating the current situation with respect to turbulence and manouvers to arrive at an optimum solution, using aiding when available in very specific circumstances where there are guaranteed benifits. The basic idea is to get your gyros to perform as best as possible, correcting for any "built in" errors and imperfections - then use the accelerometers as little as possible for purpose of error correction (if you have little error, don't do a lot of correction if the correction can sometimes be wrong - but not for long).

There is a lot to this and there are quite a number of text books filled with all the details at an academic level if you are interested in all the exact details.

I personally blame a lot of the grey hair on my head on our long line of AHRS systems. To be honest, I am only in recent months truly happy with the performance of the low cost systems. It's been a long and difficult road.

Now we are about to release high performance systems using some very nice gyros aimed at the more professional sector of aviation (to do our new 10.4" Odyssey instrument justice). These gyros are more expensive of course but still, our systems are a fraction of the cost of equivalent performing systems using the same gyros. What I find particulary nice is how easy the AHRS development becomes when one has the luxury of very good gyros...

Oh well, better shut up.

Rainier
CEO MGL Avionics

The truth about inertial gyros and nav

A SIMPLE EXPLANATION OF INERTIAL (GYRO) NAVIGATION SYSTEMS

The equipment, and hence the aircraft, knows where it is at all times. It knows this because it knows where it isn't......... By subtracting where it is from where it isn't ( or where it isn't from where it is, depending on which is greater ), it obtains a difference or deviation. The inertial reference system uses deviations to generate corrective commands to fly the aircraft from a position where it is to a position where it isn't. The aircraft arrives at the position where it wasn't; consequently, the position where it was, is now the position where it isn't. In the event that the position where it is now, is not the same as the position where it originally wasn't, the system will acquire a variation. ( Variations are caused by external factors, and discussion of these factors is beyond the scope of this simple explanation.) .

The variation is the difference between where the aircraft is and where the aircraft wasn't. If the variation is considered to be a significant factor, it too may be corrected by the IRS. The aircraft must now know where it was. The "Thought Process" of the equipment is as follows: because a variation has modified some of the navigational information which the aircraft acquired, it is not sure where it is. However, it is sure where it isn't and knows where it was. It now subtracts where it should be from where it wasn't ( or vice-versa ) and by differentiating this from the algebraic difference between where it shouldn't be and where it was, it is able to obtain the difference between its deviation and its variation; this difference being called error.

It's a joke but not to far off.

Aaarghh !!!
You are giving away our trade secrets !!!

Good one

Rainier
CEO MGL Avionics

gmcjetpilot said:

A SIMPLE EXPLANATION OF INERTIAL (GYRO) NAVIGATION SYSTEMS

The equipment, and hence the aircraft, knows where it is at all times. It knows this because it knows where it isn't.........

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Sooooo??

gmcjetpilot said:

A SIMPLE EXPLANATION OF INERTIAL (GYRO) NAVIGATION SYSTEMS


. However, it is sure where it isn't and knows where it was. It now subtracts where it should be from where it wasn't ( or vice-versa ) and by differentiating this from the algebraic difference between where it shouldn't be and where it was, it is able to obtain the difference between its deviation and its variation; this difference being called error.

It's a joke but not to far off.

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So if I shouldn't be here but I was, am I now not going to be where I though I should be....er...or wasn't meant to be?? Sheesh, grey hairs yes

Keep on keeping on,
Pierre

Robb,

It is now August and I still dont see any forums on your website. You said in May that it would be four weeks? what happened?

- Matt