Instrument Failure

Guest Discussion
1

With all the discussions about the chute problem and Cirrus’s quick reaction to address the root cause, why aren’t there any discussions about the alleged failure of the instruments that resulted in the initial loss of the aircraft in Lexington?

While it had brought out the worst of the CAPS, I’m more concerned about any weak areas of the SR2X that might force me to use the chute in the first place.

I have been doing the business travel from hell, so I might have missed some discussions on this issue.

FWIW, I am still very excited about picking up our SR22 in 60 days, 6 hrs and 3 minutes (and counting!).

Walt N224AZ

2

Your point of “alleged failure” of instruments is an important one to make.

3

Walt,

Jim Devries made this post containing the prelim NTSB report, which is the most descriptive I’ve seen regarding the actual instrument failues.

Though we all know the prelim reports are just that – preliminary – and are sometimes proven incorrect during the investigation, it seems to point to TC failure (while the A/P was using it) as the root cause.

Steve

4

Wally, I guess there are those who will hang on to ‘the alleged’ thing for as long as they can. However, their were 2 pilots who first stated the ‘Instruments went wrong’ and THEY deemed ‘unreliable’ in IMC.
If this was an ‘occasional’ occurence, there would be less need for alarm…But, if you have followed this site for a substantial period of time…you would /should know there are ‘numerous’ failures of vac pumps, HSI’s, AI’s etc. Every major components of the instrumnet deck have crashed… often. Now the TC’s which frankly have been few, are now having trouble. So is it logical, with history, that those instuments failed those guys…bet on it.
I have pleaded for a long time with Cirrus and their cheerleaders on this site…to pin Cirrus to the wall on these issues ‘before’ CAPS ARE PULLED…there will be more deployments if these other consistent problems are not fully resolved with the intensity of the CAPS.
My plane has had 4 vac pumps, 3 hsi’s and an AI. I guess the TC is next! The larger problem with these are the delays…you have to take your plane to the avionics shop…they agree its bad, wait 2-5 days from Century for example for the same dam problem you addressed 90 days before. If you were able to poll the owners, most have had repitive failures of instruments and related.
EVERY time I asked Cirrus for clarification, I get prompt attention…but NO resolution.
I hope that you are obviously acquiring a new plane, these bugs and their eggs are extinct.
Godd luck with your 22

5

And to those who are constanly up my ass about being ‘negative on Cirrus’, i want you to KNOW none of us WANT to be that way…Cirrus has given us ,sadly, a ton of reasons to feel the way we do…When 30% of your time is ‘shuttling’ to the service center and having to struggle for return transportation for the same dam shit…well, you also know dam right well you’ll be back again soon. Some call it heartbreaking, I call it ‘ball bustin’.
We need COPA and other owners to STAND with us and get this stuff ‘permanently resolved’…
Let’s together just get the MAJOR stuff handles…nobody is sweating minor issues.

6

I totally agree with Walt and Don that there is a substantial problem with the instruments and avionics on the Cirrus. So far, we have had 4 HSIs , 1 Vac pump, and, curiously, last week the first TC failure, that pretty much coinciding with the SR20 crash. Besides, there are continuing problems with the electrical HSI and the S-TEC55. These components are indeed reliable, well proven and work better in other aircraft, which leads me to this conclusion:
Either the TC, HSI and AP on the Cirrus are not “communicating” well or have not been carefully optimized to work together which eventually triggers one instrument to fail another, OR, there is a substantial problem with the electrical system of the Cirrus which fails the electrical instruments so regularly.
We’re also really tired of getting the plane to the shop so many times (about half of our flying is to and from the shop these days!) but when our warranties run out, things are going to hurt even more because nobody of us should be so naive as to think that the problems will suddenly stop at that time!
The problem seems to be that Cirrus keeps replacing those bad instruments no matter if they have to replace parts worth a second airplane, without getting behind the problem.

Phil N199CD

7

Curious that this was the second TC “failure” in this airplane. Does this seem odd to anyone else? My recollection is that electric TC’s are pretty reliable.

8

It seems VERY odd and deserves careful investigation. Turn Coordinators tend to be very reliable. One wonders about wiring to the instrument or other factors extrinsic to the instrument itself.

9

In re-reading the NTSB prelim, note that they took and will investigate the roll-trim actuator as well. Lots of possible hypotheses…

Cheers
Rick

10

I don’t think that it is clear that the TC failed. All we know is that the pilot set heading mode and moved the heading bug to turn right to 090 from 040. Next thing he knew is that the TC indicated a steep left bank with no flag and that he was losing altitude rapidly. The TC could have been correct and the autopilot might have put him in a steep left bank and the nose might have dropped if the autopilot did not put in up elevator to maintain altitude. I still have a couple of questions. Are all SR20 TC’s the same or does it depend on the autopilot and do they have flags? Do we know which autopilot was in the plane?

11

In reply to:

I still have a couple of questions. Are all SR20 TC’s the same or does it depend on the autopilot and do they have flags?

Jim,

There are at least two types of TC in the SR20. For those with the S-Tec System 20 or 30 autopilot, the A/P is actually built in to the TC – there’s a knob and mode indicator LEDs on the TC face to control the A/P.

For those with the S-Tec 55/55X A/P, the A/P exists as a separate box in the radio stack, and the TC is more conventional.

Attached is a pic of the S-Tec 20/20 style TC – I assume the “conventional” TC will be a familiar site to everyone.

I do not know whether the internal TC mechanism of these two units is the same or not, since I think they are both made by S-Tec.

I know that mine (S-Tec model 30) DOES have an indicator flag but it is not the most obvious – again, see the picture and look for the small red flag above the right wing. I’m quite sure the other style TC also has a flag but don’t know if it’s any more obvious than mine.

Steve

12

Hi Don,

BTW, when I wrote the post, I didn’t use the word alleged to imply that the pilots were lying or blaming fully operational instruments for the crash. I’m sure that two instrument rated pilots know how to stay out of trouble in the clouds and know what they saw.

Since I wasn’t there, the word alleged just came to mind. Nothing sinister implied.

I have read the NSTB report and previous threads on instrument failures, vacuum pump failures etc. In the 6 years that I owned my 1979 Warrior, I only had one marginal instrument failure. I didn’t like the way the attitude indicator was waking up and had it replaced while I was upgrading all of the avionics. Something isn’t right.

I think we both agree that Cirrus needs to put in the same effort into solving this issue in parallel with the chute problem. (I’m glad I’m not in the aircraft manufacturing business! It so much easier designing integrated circuits with only a million transistors to worry about.)

Walt N224AZ

13

Don,
My fourth HSI is on its way from Cirrus to the Avionics shop and I have been thru one AI already (275 hours on the SR20). By any measure, the Century HSI was a disastrous choice. When it works, it is a joy to fly and much less complicated than the Sandel.
What I don’t think CD ought to do is to completely replace the Century with the Sandel. Frankly I don’t know all the features of the ARNAV and throwing another gadget in the cockpit, no matter how marvelous, is getting near overload for me. The SR20 is supposed to be more of an entry level Cirrus for the lower time pilot. Surely there is another HSI out there that is simple, reliable and affordable.
What CD MUST do is dump the bleeping Century HSI immediately. Changing AI’s wouldn’t be bad either because the failure rate is relatively high. Overall, the rest of the instrument package works well in my plane. Love the whole Garmin package and, while the STEC 55 autopilot can sometimes hunt too much for an altitude, it has always been reliable even if it does porpoise a little.

Those of you waiting for an SR20 should demand another choice. The Century 1000 does not work reliably and holding you up for another $5,000 to upgrade to the Sandel ain’t right.

14

Steve -

The flag on the “TC only” turn coordinator installed with the 55/55X is also VERY hard to detect. Probably worse than your attached picture. Which is a worry when flying iFR by hand.

With the autopilot engaged, the AP detects the failed TC (or at least it does so when you pull the power to the TC). So, that is somewhat better.

Still, no substitute for an active scan and instrument cross check. The flag on the AI is hard to miss.

Bob

15

Just to add to Sreve’s post: The autopilot in the downed plane had the s-tec55 which does not have the TC in Steve’s picture.
Brian

16

I’ve been pretty silent on these boards for a couple of months, but have been monitoring. I thought I’d share some of our problems with the Cirrus. Our airplane an SR20 has had a very large number of problems. However none of them have resulted in a grounding. So we’ve been very tolerant. BUT, we have a service center on our field so when a problem arises, we just call up, they come to the hangar, work on it, and put it back. It’s been into the shop for warranty problems no less than 10 times over the last 6 months. Perhaps more. There are still too many problems that can’t be resolved in the field, so my partner is flying the plane back to the factory tomorrow. Again, none of these have been major, but annoying none the less.

Some examples of problems that I think are safety related:

We have a B model with a STEC 30 where the autopilot has NEVER worked properly. On the FIRST training flight it flew to the right of course in NAV mode, and a couple of degress off in heading mode. They adjusted it and on the second day of training it consistently flew to the right of course in nav mode and correct in heading mode. There was also a pronounced “wing rocking” while on autopilot. They replaced the autopilot. Wing rocking stopped, but the plane still flies to the right of course. It wasn’t noticed there though and got flown home.

Had onshop field shop look at it and even took them up for a test flight and it still flew to the right of course. No one can figure it out. Noticed then that on certain frequencies when transmitting, the plane pitches down. Back into the shop for a replacement part. That problem is fixed but still flies to the right.

On a cross country trip, I made alone (IFR in VMC) I’m head down folding a chart and lookup and realize I’m in a turn! Fly the plane, adjust and realize the plane is not flying the heading bug. Disconnect the autopilot and realize the TURN COORDINATOR HAS FAILED AND IS SHOWING A LEFT TURN with NO FLAG. I switch to battery power for the TC and it still doesn’t work. Cover it up with a post it and fly the rest of the trip without autopilot. Come back home VFR of course and the TC works fine on that flight. This seems like a similar failure that happened to the gents in KY. We have the TC replaced. (Note this is our fourth autopilot component).

Of course you know that the plane STILL FLIES TO THE RIGHT OF COURSE! The avionics shop says that the autopilot is correct during their ground tests. Cirrus decides that the plane may be out of rig. They want us to fly up high, go into a moderate dive and turn the airplane in each direction to measure roll rate. It does turn faster in one direction over the other. So they send a template to the service center who says that the TEMPLATE DOESN’T EVEN FIT SO THEY CAN’T TELL! Frustrated we call Cirrus and they say to bring it back for them to look at. Two months of weather and other delays go by and we are going to the factory tomorrow.

A different autopilot problem occured to my partner last week in which the autopilot disconnected and turned the airplane left while on an approach in IMC. He went missed and came in the second time. Note, there was no failure of the TC but a disconnected autopilot. He’s mentioned that this has happened to him twice.

Other problems include the Sandel didn’t fire up during training. Cirrus sort of blew this off because we couldn’t reproduce it, which I wasn’t happy with, and so luckily it happened again while we were still there and showed them. They then replaced the Sandel software. The Sandel has failed numerous times on intialization which turns out to be a software problem, but the fix isn’t yet available I don’t think.

Our transponder still doesn’t work right. While these problems have been widely reported, they’ve seemed to have died down lately. Ours doesn’t work reliably. The avionics shop says it is a directional problem with the antenna being blocked. I don’t think that is all of the problem. On many occassions, resetting the transponder (either just hitting the ALT key, or turning it off and on) will bring it back on the controllers screen. That seems odd for a solid state device, but experience proves it works much of the time.

We’ve had the ELT just go off while in flight. (no turbulence)
We’ve had the copilot door COME OFF (on the ground) while a passenger got out. We could easily put it right back in the hole, but that’s concerning us of course. The service center couldn’t duplicate it. In fact, they couldn’t even remove the door at all. My supposition in this case - I was flying a long trip at below freezing temperatures (VFR) and the metal pins that hold the door on contracted enough that the door came loose when opened. We told this to Cirrus, but they didn’t seem interested. Obviously, I think this could be a problem.

Our HID light bracket has broken. Although this didn’t result in the light not working, I still consider this a safety issue which is the reason we purchased the HID in the first place.

An alternator wire has broken. This happened a very long way from home for me (IMC) and the service center I took the plane to in Florida said this is a common problem.

Loose exhaust stacks. I noticed this because of a different noise the plane was making. It was much “throatier” the other day. After getting out the exhaust stacks were asymetrical.

There are bunch of little squawks that aren’t safety issues – no big deal. But I thought I would let the rest of you know what was going on with at least our plane.

For the record, I was very pleased with Cirrus’ response to the CAPS problem. I found it refreshing that we got the letter on the Monday after the crash, and the latest one from them.

Of course, I’m not happy with the problem, but I’m sure they didn’t think these would be problems so they are fixing them as best that can be done.

I’ve talked to BRS a couple of times (once before the KY crash and once after) and found them quite knowledgeable about the Cirrus implementation. I’m writing an article for a national firefighter magazine (I’m a volunteer fire chief in VA) on small plane accident response and the CAPS hazard to rescuers and found BRS responsive and correctly concerned. They’ve sent me quite a bit of stuff on their products and how they work and I’ll be presenting a small presentation about the Cirrus’ unique hazard to rescuers at an aircraft rescue and firefighting class next weekend.

My point is that while we all have problems with these airplanes, I’m still very happy about my choice. BUT it doesn’t mean that we shouldn’t pressure everyone involved to make sure that our families are as safe as they can be and that the respective manufacturers and Cirrus as the integrator, work tirelessely to find the root cause of these problems rather than just fixing the symptoms until they are no longer under warranty.

Derek Rowan

P.S. For my article, I’m looking for which fire departments responded to the various crashes of Cirrus aircraft (particularly the ones in MN and KY) so I can contact them about their response. If you know of the fire departments (or even crew members within), please let me know. Thanks!

17

nothing ‘sinister’ implied or taken…my parallel and now others agree is ‘with all the failuers’ bet theirs did too.
I hope we can get COPA as aroused as the chute failure…if not there WILL be more pulls and unfortunately, those wanting an inflight test will get it…But, they may be the ‘test pilot’ OUCH…That wasn’t in my or their contract!
BTW, I was flying this afternoon in some ‘mild’ rough air and was tossed about pretty good…I would be lying if I said I only had about 50% of confidence in my ‘chute’…and I had BOTH SB’s completed.
Take care,

18

In reply to:

My fourth HSI is on its way from Cirrus to the Avionics shop and I have been thru one AI already (275 hours on the SR20). By any measure, the Century HSI was a disastrous choice. When it works, it is a joy to fly and much less complicated than the Sandel.

Brig,

Is your Century vacuum or electric powered? One thing I suggested to Don (privately) is to make sure they check his vacuum system for any contaminates. Losing 4 vacuum pumps, and (if I remember right) 3 vacuum driven HSIs and a vacuum driven AI seem to point to a potential vacuum system contamination.

Personally I have a vacuum driven Century and had the glideslope fail twice. So I’m not saying they’re great instruments, but Don’s case (Century AND pumps AND AI) seemed a little worse than most.

Steve

19

I have complained in the past about the nosewheel shimmy on my SR22 (fortunately, now resolved). However, I should mention on the positive side that in 150 hours of flying our SR22 the only avionics problem was a slight nosedown pitch command when transmitting with the A/P engaged. That problem was caused by a faulty altitude hold sensor and was fixed under warranty. Also, the A/P still tracks the ILS 1/2 dot right of course but I understand that there is an adjustment I need to get around to making when I have someone qualified to operate the screw driver in the right seat during a practice approach. The T/C, AI and Sandel EHSI have all performed flawlessly. Any issues during IMC have been entirely my doing :>)

I hope those of you with avionics problems get them worked out quickly. However, not all the planes are experiencing these issues.

George Savage
N747SJ

20

thansk brig…,
I too am happy with the garmins and esp. the ARNAV with engine monitoring…I was really talking about my mentioned items.