GI 275 TORTURE TEST!!! AHRS Performance with loss of airspeed and GPS.

[@carlbandysr5058]

Awesome practical research project. I-275 seem worth the money.

[@chriskoppel3940]

They are!!

[@garyrisley9170]

Thank you for your videos on the GI-275s. I am having them installed next week and your work has been very helpful.

[@chriskoppel3940]

You are very welcome Gary!! Hope this one gives you more confidence in them

[@whiskeybravoaviation]

Great job Chris. Our Tobago goes into the shop next week to get dual GI275, GPS175 etc so this was great to see.

[@chriskoppel3940]

Gald you liked it!

[@MrLKHen]

Chris, at 10:15 with the attitude indicators obviously not in agreement, do you have a reason why the a yellow ATTITUDE miscompute did not illuminate?

[@chriskoppel3940]

Good question MrLKHen!! I am not really sure but I assume that since they are already in reversionary mode they would not announce a discrepancy, whereas they do show a yellow discrepancy annunciation at 27:00. The airspeed Red-X has gone away at 27:00 and so not in reversionary mode and so may enable the annunciation. Just an assumption since I have not asked the Garmin developers.

[@MrLKHen]

@@chriskoppel3940 thanks for the reply Chris. I’m like you, not really sure and that’s not a very good feeling.

[@chriskoppel3940]

However, a discrepancy is not sufficient to cause a failure and therefore does not go into reversionary mode.

[@bigdaddie40]

Hi Chris. We have a M20K with a KFC200 A/P. I'm debating on how to proceed with a panel upgrade. My first thought was Dynon (when their A/P is certified for the M20) as those displays are gorgeous and pleasing to my old eyes. Are the 275s easy to see despite their small size and abundance of information? Would you pursue this upgrade again or go another route? Thanks, Steve

[@chriskoppel3940]

Hi Steve, I also have “old eyes” LOL! Wear trifocals to boot!! The displays are surprisingly very bright in any light condition and easy to read. The one item that is possibly a bit small is the VSI since it is a number just below the ALT and with an up or down arrow. One gets used to the VSI after a few flights. Otherwise I have had no issues whatsoever using them. The co-pilot may find it just a bit more difficult than with a larger screen though. I would go with the same setup if you were to keep your KFC200 for a while because they are the most cost-effective upgrade with the most features in the market to replace your six-pack and keep your legacy A/P. If you already know that you want to upgrade the A/P, you may want to explore a G3X (nice large display) with a GI 275 standby ADI (or a G5) and a GFC500. I am not sure how the Dynon units work when you lose panel power (and therefore GPS) as well as pitot input. They may red-x the AI and possibly rest of the unit. The math involved in keeping the solid state gyros up and running without IAS and GPS is quite advanced. As you see Garmin AHRS units have superb performance. Unlikely other manufactures’ units do the same. As an aside, the display and features in the GI 275 is much superior than the G5. The cost of installing the Dynon you are looking at (PFD, backup AI, A/P) may not be much different thanGarmin (G3X, GI 275 stby ADI, GFC500) Garmin dual GI 275 + GFC 500 may be the least cost. You are welcome, Chris

[@n9878f]

How did you change the garmin pilot synthetic vision gauges to what you have set with vertical speed etc…?

[@chriskoppel3940]

I don't believe there is a setting for me to change anything on the synthetic vision page in Garmin Pilot. If it does not get KIAS, Baro Altitude or heading then it will revert to the GPS values. That is what I understand. May be wrong though.

[@GrumpyBumpy]

Great video. I am curious as to how you failed the pitot system? Pitot cover or disconnected lines? Does the 275 provide for an altitude preselect on your AP or do you have to do that manually?

[@chriskoppel3940]

Still trying to figure that one out. No altitude preselect with my KFC150. GI275 gives aural annunciation when 200 ft from target altitude and visual (white background on ALT) when within 1000 ft.

[@whiskeybravoaviation]

Hi Chris… we are just going through the same install at present. Quick question if I may? Do you have a switch install to select the MFD to become PFD? There seems to be a bit of debate as to whether this is supposed to be there or not!

[@chriskoppel3940]

Yes, I do have that manual reversionary switch. Per STC it is required if you are using the second unit as an MFD/Standby ADI. If memory serves me correctly it is definitely required if you are replacing the six-pack with both units. Not 100% sure if it needs to be in place if you are keeping Airspeed, TC, altimeter and VSI. The installation manual is quite clear on that. I’ll have to dig up the sections that deal with it and report back. It is not expensive at all and does not take up much space either.

[@whiskeybravoaviation]

@@chriskoppel3940 Thanks Chris that would be very helpful!

[@anthonycyr9657]

looks like a mooney panel..

[@chriskoppel3940]

It is. :)