jamesm Posted June 20, 2020 Report Share Posted June 20, 2020 I finally got just about everything working like have wanted it to. I had installed 2 G5's 1 GNC -255 (Nav/Com) GNC-355(GPS/Com) GAD13 (OAT) GAB29B(A429/CAN Converter) and CGR-30C&P. I have been making a lot of little tweaks getting all the settings correct just about there. Then BAM pow right in the kisser the STUPID POS mechanical turn coordinator dies AGAIN. I bought this particular one in 2017 just after Brittan Wing level Turn and Bank dies after 50 years this was after I had just had my ADS-B installed. This particular one has been in the shop at least 3 times. Seems that have I gotten the Hangar queen and saved it from being spare parts donor. I am think of starting my Instrument training finally fighting with the GNC-355 (mic gain Issue) might be solved. the mechanical turn coordinator dies again. My question(s) are what are my (legal) alternatives ? I really don't want repair or install another mechanical turn coordinator . Is there another alternative instead of repairing another failure pron mechanical gyro ? like a GI-275 but be legal . Since the dual G5's installation doesn't allow me to remove the T/C since the G5 is my primary Attitude indicator. At least that is my understanding of the G5. STC. I am I missing something ? Another off the wall question.... This may be obvious for most of you out there and I am embarrassed to admit .... but I always assumed that if I flew bank turn at the standard rate (2 minute marks) on the T/C it would consistently put on the same heading that I started the turn on . I was kind of getting frustrated when I was flying several scenarios at standard rate turns for given 2 minute time period that heading would be way off like 30 degrees or more. I had mentioned it to the person giving my BFR and they said that these Turn Coordinator are notorious known for being off. Is this true ? DId I miss this in my pilot training. How in heck can we have instrument so far off but yet it is a required instrument? if our static instruments had that much error in them I would expect that there would be a lot more fatalities out there. Thanks in advance, James '67C Quote Link to comment Share on other sites More sharing options...
carusoam Posted June 20, 2020 Report Share Posted June 20, 2020 James, Do you know you definitely have a TC, not a TnB? Do you know you can Easily check As you fly through the 90° marks you can check the elapsed time? Did you know using CloudAhoy will help you identify where your timing is compared to your turn.... and give you a grade as if you had a CFI on board? Based on aircraft year, you might have the notoriously less accurate, TnB... How coordinated were your turns? How quickly did you enter and exit the turn? Lots of variables... CloudAhoy eliminates variables... TCs are crummy instruments... TnBs are even worse... If you have a second attitude indicator... and a ball (for coordination).... you have what you need, and are in better shape than somebody with one AI and a TC... Modern training for the IR uses a combination of ASI and bank angle to simulate the TC.... Fly 90kias and 17° banks, time the turn for 2 minutes and see if you have finished the 360... This is all basic instrument stuff that should be easy to find in your IR textbook... Discuss your equipment with your instructor so there are no surprises... If you have two AIs and digital ball... you shouldn’t need anything more for that exercise... TnBs and TCs were always back-ups to the AI... nobody had second AIs because they were so expensive back in the day.... Today, TCs and TnBs are insidious devices...some days they work well... but on bumpy days they become un-followable.... Which is OK if you only lose your AI on smooth bumpless days... Pick a bumpy day and try to follow the average of your your wagging TC... PP thoughts only, not a CFI... Best regards, -a- 1 Quote Link to comment Share on other sites More sharing options...
jamesm Posted June 20, 2020 Author Report Share Posted June 20, 2020 it is definitely a turn coordinator so says the label on the instruments on the instrument. Do you know you can Easily check As you fly through the 90° marks you can check the elapsed time? As I recall the 1 minute mark seem some what accurate and I think left turns were the worse, I didn't check at the 90° intervals. I believe I was coordinated I did several flights in smooth air but couldn't say with absolute certainty. I did buy an experimental 2.25" turn indicator Belite RADIANT TURN COORDINATOR since it give the actual rate of turn value but never installed.I wanted to verify my T/C also I had taken it into the instrument shop to verify rate of turn portion of the instrument they said it was ok. How quickly did you enter and exit the turn? I don't recall them being abrupt but can say with absolute certainty. I didn't know that about Cloud Ahoy I was too cheap to pay for yet another service. I guess I was naive about T/C & T-n-B & Turn indicators instruments. I thought that since it was used instrument flying they were lot more reliable than I am finding they really are. The G5 does have Turn Indicator (not sure of the exact name Garmin calls them) I believe they take in account for ground speed and other factors that go into constant rate of turn. rather throwing good money at a bad instrument.I was hoping for alternative legal solution to my existing setup. I guess I need to find out if the GI-275 would be a possibly. James Quote Link to comment Share on other sites More sharing options...
carusoam Posted June 20, 2020 Report Share Posted June 20, 2020 James, the timed turns are only intended to get you in the neighborhood... The magnetic compass has its own Mechanical challenges... But, the two together... can have you turning to a new heading and be on that heading pretty quickly... Once you have declared the E word... you are going to get priority and doing full 360s won’t ever be a need... Keeping up with what is legal from a paperwork standpoint seems to be changing over time... a pair of G5s has everything needed to be a back-up for one another... If one suddenly goes dark... be ready to be able to switch the other to keep the sunny side up... Think what it would be like in bumpy IMC... If you lose your only AI... you are welcomed to use the E word... We lost a V-tail over CT in recent years... The pilot lost his AI... while above the clouds... enter the clouds using the TC... exited the clouds in pieces.... Adding to the tragedy was there wasn’t a lot of IMC.... It was somewhat localized and should have been easy to handle... PP thoughts only, not a CFI... Best regards, -a- Quote Link to comment Share on other sites More sharing options...
jamesm Posted June 20, 2020 Author Report Share Posted June 20, 2020 Thanks for the clarification ... "the timed turns are only intended to get you in the neighborhood... " As I stated before I always thought with procedure turns and holding patterns as part of the instrument flight regime I thought that the T/C were more accurate and reliable than the shown me to be. the proverbial "they" said to trust your instruments.... my response is sure when you give me accurate and reliable instrument then I will comply. I just want to verify that the G5 STC states that the T/C can be removed with dual G5 installation. much like the vacuum pump and instruments can be removed with dual G5 installation. Quote Link to comment Share on other sites More sharing options...
carusoam Posted June 20, 2020 Report Share Posted June 20, 2020 The system allows for a a whole bunch of flexibility... We train to be within certain limits... It isn’t published how human we are allowed to be and still stay within the lines.... mostly because every approach has different mountains that get in the way differently.... As for what has to stay and what can be removed... that is specific to your equipment... Wait for the G5 guys to come along for more specific answers... we have a couple of instrument shop guys and many G5 users around here... Best regards, -a- Quote Link to comment Share on other sites More sharing options...
Ragsf15e Posted June 20, 2020 Report Share Posted June 20, 2020 58 minutes ago, jamesm said: Thanks for the clarification ... "the timed turns are only intended to get you in the neighborhood... " As I stated before I always thought with procedure turns and holding patterns as part of the instrument flight regime I thought that the T/C were more accurate and reliable than the shown me to be. the proverbial "they" said to trust your instruments.... my response is sure when you give me accurate and reliable instrument then I will comply. I just want to verify that the G5 STC states that the T/C can be removed with dual G5 installation. much like the vacuum pump and instruments can be removed with dual G5 installation. The TC can be used (with lots of practice) to keep the clean side up after ADI failure, however, it’s not gonna be perfect. Anthony nailed it “in the neighborhood”. 30 degrees seems like a lot to me, but at 15-20, I’d say great job! I don’t have the STCs in front of me, but I believe you’re stuck with something there along with the G5s. My TC is my autopilot head, so it wasn’t an issue when I got 2xG5s. I knew I was keeping it. Now, I think you can probably replace the TC with a GI275 or some other type of ADI if you wanted. There’s a relatively old FAA letter about this. 1 Quote Link to comment Share on other sites More sharing options...
Niko182 Posted June 20, 2020 Report Share Posted June 20, 2020 you can replace it with a 275 or a mid continent instruments electric AI with a ball. 1 Quote Link to comment Share on other sites More sharing options...
jlunseth Posted June 20, 2020 Report Share Posted June 20, 2020 We went through this on another thread I believe. The 275 can be a legal replacement for a TC, it comes in a version that is certified as primary for the TC. Needs to be the correct version of the 275, there are several, and I believe it is necessary to install an OAT temp probe kit for the 275. The 275 displays two little turn indicators at the top of the circular display that vary depending on airspeed, temp, etc. to provide a turn indication. I am pretty sure it also has a ball function (going from memory there), but the problem would be no backup ball if the 275 stops displaying. You can use the AI as a backup for the TC, but there is no good backup for the ball. The simple fix would be to install a simple analog ball. Quote Link to comment Share on other sites More sharing options...
EricJ Posted June 20, 2020 Report Share Posted June 20, 2020 (edited) Here's what my copy of the G5 STC sez: "The installation of the G5 requires the retention of the mechanical airspeed indicator, altimeter, and vertical speed indicator. If the G5 is installed as the primary attitude, it requires retention of the existing rate of turn indicator. If installed in place of the rate of turn indicator, it requires retention of the existing primary attitude indicator." I think one of your G5s is installed as a primary attitude indicator and the other as a rate of turn indicator. I don't think you need to replace your failed rate of turn indicator, but that's just me. Your IA should be the deciding opinion as he has to sign it off every year. Edited June 20, 2020 by EricJ 1 Quote Link to comment Share on other sites More sharing options...
Bob - S50 Posted June 20, 2020 Report Share Posted June 20, 2020 9 minutes ago, EricJ said: I think one of your G5s is installed as a primary attitude indicator and the other as a rate of turn indicator. I don't think you need to replace your failed rate of turn indicator, but that's just me. Your IA should be the deciding opinion as he has to sign it off every year. Pretty sure the STC says the G5 can be used as either the attitude indicator OR the turn coordinator replacement but NOT both. Other options for replacing the TC: Dynon D10A , uAvionics AV30 (when certified), mechanical AI, RC Allen RC-2610, Sandia 340 Quattro, ESI-500, GI275, KI300, and probably more. 1 Quote Link to comment Share on other sites More sharing options...
EricJ Posted June 20, 2020 Report Share Posted June 20, 2020 (edited) 8 minutes ago, Bob - S50 said: Pretty sure the STC says the G5 can be used as either the attitude indicator OR the turn coordinator replacement but NOT both. Other options for replacing the TC: Dynon D10A , uAvionics AV30 (when certified), mechanical AI, RC Allen RC-2610, Sandia 340 Quattro, ESI-500, GI275, KI300, and probably more. If you have two G5s one replaces the AI and one replaces the TC. That's my view. Edited June 20, 2020 by EricJ Quote Link to comment Share on other sites More sharing options...
Vno Posted June 20, 2020 Report Share Posted June 20, 2020 From the manual talking about the STC: Use of Secondary Instruments: The original type design approved instruments for airspeed, altitude and vertical speed remain the primary indications for these parameters. If the G5 Electronic Flight Instrument is installed in place of the rate of turn indicator, the original type design approved instrument for attitude remains in the primary indication for attitude. If the G5 Electronic Flight Instrument is installed in place of the directional gyro, the original type design approved instruments for attitude remains the primary indication for attitude. NOTE:For aircraft approved for VFR-only operations, the G5 Electronic Flight Instrument may be installed as an attitude indicator and rate of turn indicator. I'd be surprised if an A&P would sign off on dual G5s without the opposing supporting instruments. You might want to ask your A&P or avionics guy if they would sign off on a non-TSO Turn Coordinator install. It usually is less expensive and the instrument will probably work just as well as a TSO version. That instrument is rarely used except in an emergency. Brian Quote Link to comment Share on other sites More sharing options...
Steve W Posted June 20, 2020 Report Share Posted June 20, 2020 AC 91-75 says you can replace the TC with an Attitude Indicator with a Ball, but does require different power sources. In my case that was going to be an RC Allen 2610 with their backup battery and screw-on ball. Now they have an updated 2610 with an internal battery, digital ball and digital rate of turn indicator and I think that's what I'd go with(honestly finding a place to put the external battery was a pain) Quote Link to comment Share on other sites More sharing options...
Ragsf15e Posted June 21, 2020 Report Share Posted June 21, 2020 8 hours ago, EricJ said: If you have two G5s one replaces the AI and one replaces the TC. That's my view. At first I was gonna (nicely) say you were crazy. However, from the STC quoted above, it appears you can install them that way if your airplane is vfr only. Typically, IFR installations of 2 G5s are installed as The ADI and HSI and we must keep the analog instruments and the TC. AC 91-75 quoted above gives us the ability to remove the TC and install some other type of ADI as long as it still has a ball for coordinated turns. So I’ve never seen or heard of installing a G5 as an ADI and another as a TC, but apparently you can if you’re not interested in IFR. However, I think I’d rather have a nice G5 HSI than a fancy G5 TC. Quote Link to comment Share on other sites More sharing options...
EricJ Posted June 21, 2020 Report Share Posted June 21, 2020 (edited) 3 minutes ago, Ragsf15e said: At first I was gonna (nicely) say you were crazy. However, from the STC quoted above, it appears you can install them that way if your airplane is vfr only. Typically, IFR installations of 2 G5s are installed as The ADI and HSI and we must keep the analog instruments and the TC. AC 91-75 quoted above gives us the ability to remove the TC and install some other type of ADI as long as it still has a ball for coordinated turns. So I’ve never seen or heard of installing a G5 as an ADI and another as a TC, but apparently you can if you’re not interested in IFR. However, I think I’d rather have a nice G5 HSI than a fancy G5 TC. What's the limitation for VFR only? There are currently a lot of IFR airplanes out flying around with no separate turn coordinators at all, I just did 10 hours in a Seminole that is less than a year old that has no separate turn coordinator, and also no compass. Totally legal IFR machine, believe it or not. Edited June 21, 2020 by EricJ Quote Link to comment Share on other sites More sharing options...
N201MKTurbo Posted June 21, 2020 Report Share Posted June 21, 2020 I like my TC, but then I’m an old steam gauge guy. Quote Link to comment Share on other sites More sharing options...
N201MKTurbo Posted June 21, 2020 Report Share Posted June 21, 2020 Ok, I just got back from a flight that I was conned into, flying a hangar neighbor’s Charokee 6 IFR to Catalina. He has no instrument rating. His plane has dual G5’s but no autopilot, so I had to hand fly it the whole way. Call me a wuss, but that’s a big pain in the ass. Holy crap, looking something up on the IPad and flying at the same time isn’t easy, it’s like correct the heading, correct the altitude, poke one finger on the IPad, repeat, I miss my autopilot! I kept thinking “I miss my Mooney” 1 Quote Link to comment Share on other sites More sharing options...
Ragsf15e Posted June 21, 2020 Report Share Posted June 21, 2020 1 hour ago, EricJ said: What's the limitation for VFR only? There are currently a lot of IFR airplanes out flying around with no separate turn coordinators at all, I just did 10 hours in a Seminole that is less than a year old that has no separate turn coordinator, and also no compass. Totally legal IFR machine, believe it or not. Yes, but I’m gonna wager it has two ADIs. Like a G1000 has some type of backup ADI... no TC, but the two ADIs is acceptable. For new airplanes such as G3000, Cirrus, etc. They are certified with specific equipment and generally have a backup ADI that has its own power source. Basically they are meeting the same standard as the AC reference above. I guess the bottom line is that the G5 stc itself says you can’t replace both the ADI and TC With G5s for an IFR airplane. Quote Link to comment Share on other sites More sharing options...
EricJ Posted June 21, 2020 Report Share Posted June 21, 2020 Just now, Ragsf15e said: Yes, but I’m gonna wager it has two ADIs. Like a G1000 has some type of backup ADI... no TC, but the two ADIs is acceptable. For new airplanes such as G3000, Cirrus, etc. They are certified with specific equipment and generally have a backup ADI that has its own power source. Basically they are meeting the same standard as the AC reference above. I guess the bottom line is that the G5 stc itself says you can’t replace both the ADI and TC With G5s for an IFR airplane. I don't think the STC says that. It references a G5, in the singular, and says a G5 can replace an attitude indicator OR a TC. If you have one of each, a G5 to replace the AI, and a G5 to replace the TC, I think you meet the STC. Consider that somebody replaces their AI with a G5 and leaves everything else alone. That airplane is totally legal to fly IFR with a single AI, being the G5, as long as it also has the mechanical air instruments and a separate TC. Later on somebody wants to put in a second G5 in the same airplane, perhaps at a totally different shop. That installer sees a legit AI installed, being the current G5, and does not disturb it at all, but installs another G5 as an HSI and deletes the TC. Both installations conform with the STC and the net result is two G5s and no separate TC and no AI other than the first G5. Quote Link to comment Share on other sites More sharing options...
Ragsf15e Posted June 21, 2020 Report Share Posted June 21, 2020 24 minutes ago, EricJ said: I don't think the STC says that. It references a G5, in the singular, and says a G5 can replace an attitude indicator OR a TC. If you have one of each, a G5 to replace the AI, and a G5 to replace the TC, I think you meet the STC. Consider that somebody replaces their AI with a G5 and leaves everything else alone. That airplane is totally legal to fly IFR with a single AI, being the G5, as long as it also has the mechanical air instruments and a separate TC. Later on somebody wants to put in a second G5 in the same airplane, perhaps at a totally different shop. That installer sees a legit AI installed, being the current G5, and does not disturb it at all, but installs another G5 as an HSI and deletes the TC. Both installations conform with the STC and the net result is two G5s and no separate TC and no AI other than the first G5. “If the G5 Electronic Flight Instrument is installed in place of the rate of turn indicator, the original type design approved instrument for attitude remains in the primary indication for attitude.” and ”NOTE:For aircraft approved for VFR-only operations, the G5 Electronic Flight Instrument may be installed as an attitude indicator and rate of turn indicator.” I guess you can find a fsdo to sign off just about anything, but I don’t think there’s much wiggle room or ambiguity in the two paragraphs above. Quote Link to comment Share on other sites More sharing options...
EricJ Posted June 21, 2020 Report Share Posted June 21, 2020 7 minutes ago, Ragsf15e said: “If the G5 Electronic Flight Instrument is installed in place of the rate of turn indicator, the original type design approved instrument for attitude remains in the primary indication for attitude.” and ”NOTE:For aircraft approved for VFR-only operations, the G5 Electronic Flight Instrument may be installed as an attitude indicator and rate of turn indicator.” I guess you can find a fsdo to sign off just about anything, but I don’t think there’s much wiggle room or ambiguity in the two paragraphs above. I'm not seeing that wording in my STC or installation manual (Rev 11). I quoted my copy of the STC earlier, which doesn't have your first quote, nor does my installation manual. Both say a G5 (singular) can be installed as an AI or a TC replacement. My installation manual says it can also be a DG/HSI replacement and places no restrictions on that. The second quote doesn't seem relevant to me, since it is referring to a single G5. My installation manual does say, "The G5 cannot replace an existing primary attitude indicator that has a Flight Director; however, if the existing attitude indicator is interfaced to the autopilot and it does not include a Flight Director, that existing attitude indicator can be moved to the rate-of-turn indicator location and the G5 installed as the primary attitude indicator." - par 1.1 So, there's an example proof of wording in the installation manual that even a single G5 can be the primary attitude indicator with the TC replaced by the AI that drives the autopilot. I've seen a number of installations like this, and I may wind up doing my airplane this way since the vacuum AI drives the autopilot and my current G5 is installed as an HSI. I know the G5 STC and install manuals, and also direction from Garmin, have resulted in a lot of confusion about this in the past, so I'm not surprised there are differences in opinions. I'm certainly not saying my opinion is gospel, either, I'm just reflecting what I'm reading in the STC and installation manual. To be fair, some of the wording in the installation manual does muddy the water quite a bit, like, "In the attitude application, the Garmin G5 indicator can replace an existing vacuum attitude indicator or rate-of-turn indicator." A strict interpretation of that would suggest that a G5 cannot replace an electric AI. Quote Link to comment Share on other sites More sharing options...
jamesm Posted June 21, 2020 Author Report Share Posted June 21, 2020 So this what Garmin online support told me ..... The G5 can be a backup to the GI-275 Primary ADI, however this has NOT been approved yet. Note: The GI 275 can receive database updates from another compatible Garmin LRUs but will only provide databases updates to a GI 275, GPS 175, GNC 355, or GNX 375. You can have either the existing analog pitot/static, DG and TC. Or, you can have another GI 275 +ADAHRS as your HSI. Or, you can have one as a MFD map next to the primary ADI. Or, you can have a G5 next to the primary ADI. The Primary ADI requires one of the following combinations of standby information: • Standby display of attitude, altitude, and airspeed • Standby display of altitude, airspeed, stabilized heading, and standard turn-rate coordination (existing instruments may be retained) I appreciate your advice and comments. Thanks, James '67C Quote Link to comment Share on other sites More sharing options...
Bob - S50 Posted June 21, 2020 Report Share Posted June 21, 2020 2 hours ago, EricJ said: I don't think the STC says that. It references a G5, in the singular, and says a G5 can replace an attitude indicator OR a TC. If you have one of each, a G5 to replace the AI, and a G5 to replace the TC, I think you meet the STC. Consider that somebody replaces their AI with a G5 and leaves everything else alone. That airplane is totally legal to fly IFR with a single AI, being the G5, as long as it also has the mechanical air instruments and a separate TC. Later on somebody wants to put in a second G5 in the same airplane, perhaps at a totally different shop. That installer sees a legit AI installed, being the current G5, and does not disturb it at all, but installs another G5 as an HSI and deletes the TC. Both installations conform with the STC and the net result is two G5s and no separate TC and no AI other than the first G5. An HSI is not a suitable TC replacement. In order for a G5 to replace the TC, it has to be acting as an AI. Eric, you seem to be pretty sure. Since there are several of us that feel pretty strongly the other way, the only way to tell for sure is to ask those in authority: 1. Write to Garmin and ask: a. If you can replace both the AI and TC with G5's. b. If you can install an AI G5 and an HSI G5 are remove the TC. 2. Then write to the FAA and ask them the same questions. Like many things in life, there are things that sound pretty good until you ask yourself if you would still do it with those in authority looking over your shoulder. I'll be very interested to see what kind of response you get from Garmin and the FAA. If I can replace the AI, HSI, and TC with 3 G5's I just might do that. But I'm not holding my breath. Quote Link to comment Share on other sites More sharing options...
ArtVandelay Posted June 21, 2020 Report Share Posted June 21, 2020 G3X, and get rid of all the steam instruments. Quote Link to comment Share on other sites More sharing options...
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