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EN48
5th Apr 2008, 18:28
I'll soon be taking delivery of an Enstrom 480B equipped with a 2 panel Chelton system. I have had a bit of training on this and can push the buttons pretty well, but have no actual in-flight experience. Wondering if anyone can comment on functionality, long-term reliability, etc. Chelton seems to have become the de facto standard for light turbines, with Bell, MD, EC, and Enstrom offering Chelton as optional equipment.

GeorgeMandes
6th Apr 2008, 02:16
We used it for three years on a Turbo Beaver and never had a single squawk with the Chelton system. It offered a lot of features for an aircraft flown IFR -- airways, TAWS, WAAS approaches, and visual approaches with a glide path.

For a VFR helicopter, flown by looking out the window and keeping two hands on the controls, it seems like a lot of button pushing compared to having an attitude indicator and a Garmin 396 or 496 paired with a 430 or 530. The bugs panel (dedicated buttons for setting heading, altitude and course without pushing multiple soft keys on the displays) has been "three months off" for the last three years. The wind vector on the Chelton is a great feature.

George

helofixer
6th Apr 2008, 03:14
I work on two aircraft with the 2 display Chelton. One is a police equipped Bell 407 and one brand new Enstrom 480B (s/n 5117) also police equipped. Both aircraft are fairly new and have had no down time issues due to a unit failure yet. On the 407 we had to tweak some settings regarding frame refresh rate and some horizion gyro display over/under sensitivity but that was accomplished while the unit was installed in the aircraft using Chelton tech support over the phone and the built in maintenance menus in the units them selves.
As for the Enstrom, it has maybe 60 hours on it since new and no squawks. Seems to be a fine system, but a few older pilots commented on that it tends to keep your head down in the cockpit more when you might be better served looking outside.

EN48
6th Apr 2008, 09:55
George said:


"For a VFR helicopter, flown by looking out the window and keeping two hands on the controls, it seems like a lot of button pushing compared to having an attitude indicator and a Garmin 396 or 496 paired with a 430 or 530. "

No question that its overkill for a VFR helicopter, but its the only game in town if you want "modern" avionics. Also, quite a few buttons to push on the Garmins as well.

Helofixer:

My 480 will be sn 5121, the second one, I believe, to be delivered by Enstrom with the Chelton system. Saw yours at HAI - very nice!

EN48

helofixer
6th Apr 2008, 22:26
I was at the Enstrom Factory March 9-20th 2008 for maintenance training so there was a good chance that if it was still there, I may have seen you aircraft in final assembly. Color? Registration # ?

EN48
6th Apr 2008, 22:46
I may have seen you aircraft in final assembly. Color? Registration # ?

Blue Angels colors (navy blue/yellow) N875JR

GeorgeMandes
7th Apr 2008, 00:55
No question that its overkill for a VFR helicopter, but its the only game in town if you want "modern" avionics. Also, quite a few buttons to push on the Garmins as well.


Sagem is certainly an option, and has been installed in the Jet Ranger, 407, Eurocopter and Sikorsky helicopters. We are hoping that the new Aspen display can be field approved -- that will bring lots of capability for a $10k unit.

George

GeorgeMandes
9th Apr 2008, 02:24
I saw the new Garmin synthetic vision software displayed on the G1000 displays today at Sun N' Fun, and it has the best elements of the Chelton software, the G1000 presentation, and amazing presentation of terrain. Not an option now for helicopters, but a glimpse into what the future will hold.

George

EN48
9th Apr 2008, 19:08
George,


but a glimpse into what the future will hold.



Unfortunately, avionics are a moving target. It seems that there is always something coming that you would like to have, but it is often months or years out on the horizon.

I did look at the SAGEM EFIS as used in the 206/407/ASTAR. This seems to be a display rather than an integrated system like the Chelton, which incorporates an FMS, TAWS, synthetic vision, and other features within the Chelton system, and it is the only such system offered as a factory install in the Enstrom 480B. No STC yet for the SAGEM, and I would guess the cost of the SAGEM with the additional equipment to duplicate the Chelton functionality would be considerably greater. However, the larger SAGEM displays are nice.

SHortshaft
10th Apr 2008, 00:53
There are several unsolved software glitches and some areas of the software that are rather 'user unfriendly' which only come to light after you have taken delivery and started trying to use the system.

Then there is the large appetite for power which in our installation required an extra battery to meet certification requirements. This eats in to the range / payload figures so much that it is commercially unacceptable.

In a light helicopter it is overkill and a commercial disaster unless you are training pilots that are going on to larger glass cockpit laden helicopters.

Avnx EO
10th Apr 2008, 01:46
Your basic comment is right, EN48. The SAGEM system is really a fairly standard depiction of traditional flight instruments. However the advantage of the SAGEM system (as in the STCs on the 407 and 206) is that it puts the engine indications "under glass." There is an option on the SAGEM system for a rather nice map capability, but they have yet to present it in an "SV" (synthetic vision) format.

It's good to see that the Sagem influence is beginning to yield results. As you may know, Sagem bought the old ARNAV company, and their prior glass implementations were mediocre in things like anti-aliasing techniques, etc. (the stair case effects you get curves, etc.) When needles and horizon lines were actually in motion, the effects of the "lego-block" depictions were really distracting. The new stuff seems to be a much better calibre.

The Chelton stuff is primarily EFIS. Chelton has worked a couple of programs to put engine "under glass" (most notably the defunct Bell 417) but at the moment doesn't appear to be there yet. They also seem to have dropped development of their larger 6"x8" displays which they stopped showing at trade shows soon after the 417 was cancelled. The SV (synthetic vision) presentation, and the ability to bring in TCAS and present FMS routing in lay-down and highway-in-the-sky is still what sets Chelton apart. The people who like that sort of thing, love the Chelton displays (my read has been about a 50/50 split.)

I noted a marked drop, however, in Chelton systems being displayed this year at HAI. I wonder if they've over-extended themselves... they were getting into everything for a while including writing the display software for the Eclipse jet.

As far as problems with the Cheltons go, the issues I've heard of are primarily in the supporting equipment. Their earlier generation stuff had a Cross-bow AHRS that has the magnetometer (flux valve) for heading built in - which means you have to mount the unit in a BAD spot for AHRS performance in order to get the magnetometer to work - or if you got the AHRS to work, the magnetometer wouldn't. :ugh: I heard of several installations where they eventually had to replace the AHRS, either immediately, or later when they added some piece of equipment near the AHRS that started creating problems.

The brand new generation Chelton displays have ADAHRS built onto the back of the display unit with a remote magnetometer. To me this is the WRONG place to put an ADAHRS. There are lots of problems that come up with panel-mounted helicopter attitude systems - so why would you voluntarily put one there? In traditional mechanical indicators, there has been all kinds of anomalies that pop up as a result of instrument panel vibration change. Helicopter OEM will generally pick through several models before they find one that works in all their configurations. Sometimes changing skid height or hanging something new off the belly will send what was a perfectly well-behaved attitude system tumbling in a certain flight condition. For a helicopter, if you can, you want your AHRS (or gyros) mounted someplace solid. Panel mounting attitude sensors is a last resort.

Also adding the ADAHRS to one display makes the units non-interchangeable (the old ones were interchangeable.)

But back to Chelton's SV....Keep in mind that Chelton is the "first generation" SV (Its still all brown below the horizon - and it doesn't depict lakes, etc.) It happened to get picked up by a lot of Helicopters and STCs a few years ago. Universal systems made the breakthrough for what I'd call the current generation SV when they TSO'd their system (announced NBAA 2006) which brough a whole new level of detail to the SV depiction. Then you could have blues, browns, and greens coloring areas below the horizon so you could depict lakes, rivers, terrain features, etc. (something useful for those of us who don't operate in mountainoius terrain.... you notice they always do the SV demo over Denver or Boise... not Kansas)... In any event Honeywell and Collins have now followed and they have some sweet systems. I have yet to see them in a Helicopter, but I know they're working it. My favorite is where they blend SV with EVS so you get a real-time FLIR image imbedded in the SV context (Since deer on the helipad are not normally part of the SV obstacle data base) ....but I can tell I've probably "geeked out" too far by now.

Enjoy your new toy, EN48...

EN48
10th Apr 2008, 03:10
Avnx,

Thanks for a most comprehensive reply. Are you sure about the mounting location of the new Chelton ADAHRS? All the informal info I have suggests that it is remotely mounted as was the Crossbow, and may even be plug compatible. Mounting it on or in the display box might also defeat the prior strategy of making all the displays interchangeable, as you suggest.

Addendum: If you go to the Chelton website (www.cheltonflightsystems.com (http://www.cheltonflightsystems.com)) it seems to clearly show the new ADAHRS as a separate remote mount box, along with a magnetometer and OAT probe.

Yes, the SV is primitive compared to more recent products from others, but AFAIK, its the only SV certified for use in light helicopters at present.

A Chelton R&D employee let slip at HAI that a next generation system continues in development - possibly a continutation of the 417 project, and no availability date mentioned.

Engine instruments on glass would be nice.

The Chelton contribution to the Eclipse jet was to have been their FMS software, not displays. IS&S does the Eclipse displays. I hear that Eclipse and Chelton have recently parted ways, and that Eclipse has announced that the Garmin GPS400W will be their "FMS."

Dont worry, there is no chance you will "geek out" me! I think of the helicopter as a platform to fly my avionics around! :)

Shortshaft,

Chelton has recently released version 6.0B software which I am told fixes many bugs and adds new functionality.