So its near the end of the road. Everything is in and wired and the final tests are being done. KOSU (Ohio State) avionics is doing a very detailed install process. Their guys came from jet shops where everything has to be perfect so my 1974 Warrior 180 is getting vetted down to its shorts. For instance, all of the legacy antenna coax was replaced with current higher quality wire to avoid sensitive GPS interference. That is one example of cleanup taking place. New circuit breakers also as well as lots of wiring refinement to clean up under the panel.
As the pix shows, everything is in place and the final compatibility checks are underway. Three GI 275s, two with ADHARS, one with Autopilot and GMU 11 magnetometer. But it looks like the magnetometer gets shared with all three GI 275s. Whatever one has they all have, except the autopilot control. Updates shared with the GTN 650xi also. The two top units were installed as the ADAHRS GI275s, but the vibration test (engine max power) showed problems. So the two ADAHRS units were switched and aligned top to bottom and this configuration passed the vibration test. The analysis being that Piper strengthened this portion of the panel area because that was the location of the ADI and DG. This is the first PA 28 KOSU has installed GI275s in so all new to them. They say new to Garmin also.
Last gremlin was magnetometer interference. The GMU 11 is in the rear fuselage behind the new ACK406 ELT. The initial test was fine. The swing test with control deflections with power power showed magnetic interference however. So they are sorting the issue out now. It seems the interference may be associated with rudder deflection so perhaps the rudder control horn is magnetized. Other possibilities are the stabilitor counterweight or magnetism associated with the grounding of the position light/strobe on the rudder. Or some other quirk. This ain't your mama's "hook up the wires" install. All this new stuff is very sensitive and requires careful vetting all the way to the end of the line.
Hopefully, by Monday all the checks will be resolved and the airplane ready for flight test. It was neat to sit in the left seat and flip the avionics master and watch the show start as everything lit up. Toggling through the GI 275 display options was really cool. You have multiple displays to choose from--the CDI view can wait until you do an approach. The MD 93H clock/USB will give me a Zulu clock/timer and 3 amp USB outlets for my approach chart IPad on the yoke. I already bought a short Lightning cable. New circuit breakers also. The temperature probe will be neat to have right on the primary instruments, especially connected to the FS 450. The KX 155 and KY 197A as well as the KR87 ADF are ready to do their part if someone flips the switch or blasts GPS satellites out of the sky.
So, studying hard and working flight plans and executed missions on the GTN simulator to get ready. Can't wait to try the roll steering with the STec 20.
Lots of capability for a 46 year old airplane, but actually better performance and payload than a new Archer LX at 1/6 the cost. So the math works for me.
Pretty capable for a 46 year old airplane but state of the art, with actually more capability, than a new Archer LX at less than 1/6 of the cost.
As the pix shows, everything is in place and the final compatibility checks are underway. Three GI 275s, two with ADHARS, one with Autopilot and GMU 11 magnetometer. But it looks like the magnetometer gets shared with all three GI 275s. Whatever one has they all have, except the autopilot control. Updates shared with the GTN 650xi also. The two top units were installed as the ADAHRS GI275s, but the vibration test (engine max power) showed problems. So the two ADAHRS units were switched and aligned top to bottom and this configuration passed the vibration test. The analysis being that Piper strengthened this portion of the panel area because that was the location of the ADI and DG. This is the first PA 28 KOSU has installed GI275s in so all new to them. They say new to Garmin also.
Last gremlin was magnetometer interference. The GMU 11 is in the rear fuselage behind the new ACK406 ELT. The initial test was fine. The swing test with control deflections with power power showed magnetic interference however. So they are sorting the issue out now. It seems the interference may be associated with rudder deflection so perhaps the rudder control horn is magnetized. Other possibilities are the stabilitor counterweight or magnetism associated with the grounding of the position light/strobe on the rudder. Or some other quirk. This ain't your mama's "hook up the wires" install. All this new stuff is very sensitive and requires careful vetting all the way to the end of the line.
Hopefully, by Monday all the checks will be resolved and the airplane ready for flight test. It was neat to sit in the left seat and flip the avionics master and watch the show start as everything lit up. Toggling through the GI 275 display options was really cool. You have multiple displays to choose from--the CDI view can wait until you do an approach. The MD 93H clock/USB will give me a Zulu clock/timer and 3 amp USB outlets for my approach chart IPad on the yoke. I already bought a short Lightning cable. New circuit breakers also. The temperature probe will be neat to have right on the primary instruments, especially connected to the FS 450. The KX 155 and KY 197A as well as the KR87 ADF are ready to do their part if someone flips the switch or blasts GPS satellites out of the sky.
So, studying hard and working flight plans and executed missions on the GTN simulator to get ready. Can't wait to try the roll steering with the STec 20.
Lots of capability for a 46 year old airplane, but actually better performance and payload than a new Archer LX at 1/6 the cost. So the math works for me.
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