EricJ Posted August 15, 2022 Report Share Posted August 15, 2022 4 hours ago, Marc_B said: @EricJ what was it that concerned you? I have a Century II installed with simple pushrod servo connections to the existing pushrod control system. The GFC500 installation requires adding a complex pulley system in the wing for cable controls, as well as cables in the tail for the pitch servo. The mechanical installation of the servos does not seem efficient or desirable to me, especially compared to the pushrod style servos used for Century or similar installations. Adding cables to an airplane with pushrod controls seems silly to me. Garmin has pushrod servos for the GFC500 system, but it's a mystery to me why they didn't use them. Quote Link to comment Share on other sites More sharing options...
N201MKTurbo Posted August 15, 2022 Report Share Posted August 15, 2022 1 hour ago, EricJ said: I have a Century II installed with simple pushrod servo connections to the existing pushrod control system. The GFC500 installation requires adding a complex pulley system in the wing for cable controls, as well as cables in the tail for the pitch servo. The mechanical installation of the servos does not seem efficient or desirable to me, especially compared to the pushrod style servos used for Century or similar installations. Adding cables to an airplane with pushrod controls seems silly to me. Garmin has pushrod servos for the GFC500 system, but it's a mystery to me why they didn't use them. I have a feeling that in their rush to get as many planes certified as possible, they were reusing as many drawings as possible. Most airplanes use cable control, so they tried to leverage that as much as possible. Maybe sometime they will have time to improve the installation. 1 Quote Link to comment Share on other sites More sharing options...
MisfitSELF Posted August 15, 2022 Author Report Share Posted August 15, 2022 14 hours ago, laytonl said: I just removed my kap150 and had the gfc500 with g5 and yaw damper installed. It was around $20-21k. Lee Where'd did you you have it done? Quote Link to comment Share on other sites More sharing options...
PT20J Posted August 15, 2022 Report Share Posted August 15, 2022 14 hours ago, EricJ said: I have a Century II installed with simple pushrod servo connections to the existing pushrod control system. The GFC500 installation requires adding a complex pulley system in the wing for cable controls, as well as cables in the tail for the pitch servo. The mechanical installation of the servos does not seem efficient or desirable to me, especially compared to the pushrod style servos used for Century or similar installations. Adding cables to an airplane with pushrod controls seems silly to me. Garmin has pushrod servos for the GFC500 system, but it's a mystery to me why they didn't use them. It’s pretty clear that Garmin copied the KFC installation. In fact, a trick some installers use to reduce cost is to reuse the BK bracket for the aileron servo. The pitch and trim servos also connect to the controls in the same fashion as the BK servos, but the brackets are not identical. Two differences I notice with the GFC servos compared to the KFC is that the force required to overpower the pitch and roll servos is much higher with the GFC since they don’t have clutches, and the GFC servos have a different torque/rpm characteristic. The latter can be noticed on the pitch trim installation where the gearing is set apparently to meet the trim speed requirement which greatly lowers the torque. The sprocket on the GFC servo is HUGE, whereas the GFC servo was geared about 1:1. Skip 1 Quote Link to comment Share on other sites More sharing options...
EricJ Posted August 15, 2022 Report Share Posted August 15, 2022 24 minutes ago, PT20J said: It’s pretty clear that Garmin copied the KFC installation. In fact, a trick some installers use to reduce cost is to reuse the BK bracket for the aileron servo. The pitch and trim servos also connect to the controls in the same fashion as the BK servos, but the brackets are not identical. I suspect what happened was somebody from Garmin decided to look at a legacy installation, maybe to use a "qual by similarity" argument for certification, and just happened to have a KFC installation to look at instead of a Century or an S-Tec. Just bad luck. 1 Quote Link to comment Share on other sites More sharing options...
MisfitSELF Posted August 15, 2022 Author Report Share Posted August 15, 2022 1 hour ago, PT20J said: It’s pretty clear that Garmin copied the KFC installation. In fact, a trick some installers use to reduce cost is to reuse the BK bracket for the aileron servo. The pitch and trim servos also connect to the controls in the same fashion as the BK servos, but the brackets are not identical. Two differences I notice with the GFC servos compared to the KFC is that the force required to overpower the pitch and roll servos is much higher with the GFC since they don’t have clutches, and the GFC servos have a different torque/rpm characteristic. The latter can be noticed on the pitch trim installation where the gearing is set apparently to meet the trim speed requirement which greatly lowers the torque. The sprocket on the GFC servo is HUGE, whereas the GFC servo was geared about 1:1. Skip Well if I were doing this myself, I'd try to reuse the existing brackets as much as possible. Especially the ones for the aileron servo -- that must have been a b**ch to install if done after wing close out. I figure they just built the wing around the autopilot when the original KAP autopilot was installed. Quote Link to comment Share on other sites More sharing options...
PT20J Posted August 15, 2022 Report Share Posted August 15, 2022 14 minutes ago, MisfitSELF said: Well if I were doing this myself, I'd try to reuse the existing brackets as much as possible. Especially the ones for the aileron servo -- that must have been a b**ch to install if done after wing close out. I figure they just built the wing around the autopilot when the original KAP autopilot was installed. I would probably do that, too. I’m continually amazed at how quickly experienced A&Ps can do things that seem impossible. My installer figured that I paid for the Garmin parts (you have to) so he might as well install them. It actually only too a few hours. Would have taken me a couple of days. Quote Link to comment Share on other sites More sharing options...
gmonnig Posted August 16, 2022 Report Share Posted August 16, 2022 Damn these are high. Approx $15k installed last year in a C model in Higginsville, MO. That was no yaw dampener though. They are doing my dual GI-275s in October and I will be certainly be going back for the GFC500 next year for my E. Quote Link to comment Share on other sites More sharing options...
201Steve Posted August 16, 2022 Report Share Posted August 16, 2022 45 minutes ago, gmonnig said: Damn these are high. Worth every cent Quote Link to comment Share on other sites More sharing options...
gmonnig Posted August 16, 2022 Report Share Posted August 16, 2022 14 minutes ago, 201Steve said: Worth every cent For sure but why pay more if you don’t have to. $11,200 for 2axis and electric trim. Figure 50hrs of work (if you already have G5s of gi275s) at $100hr. $16k seems fair but none of these quotes are near that. Quote Link to comment Share on other sites More sharing options...
201Steve Posted August 16, 2022 Report Share Posted August 16, 2022 Oh I see. Yeah, I got 5 prices in 2020. Price ranges by a $25k delta. Quote Link to comment Share on other sites More sharing options...
RightrudderM20E Posted 4 hours ago Report Share Posted 4 hours ago On 8/12/2022 at 11:08 AM, FlyingDude said: One shop here told me an autopilot on my E would be a 45k$ job. That's the same one that quoted me 1800$ "nationwide flat rate" to swap out the displays in my KX155 with LED display - but then charged me 2400$ when I went to retrieve my radio, because "there was unforeseen extra work." My guy at 3CM would do it way cheaper (haha, I know how that sounds) but he's done a ton of GFC500s on different aircraft and has great pireps. Could you pm me his info ? Looking at doing this upgrade . thanks Quote Link to comment Share on other sites More sharing options...
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