The latest Kitplanes had an article by Stein about this nylon tubing and connector system that he’s been using. I really liked the look of it, and wasn’t totally happy with all of the different tubing systems that I’d been using. So I decided to switch to it. A nice side benefit is all of the pitot tubing is green and the static is white. You can see that we’ve got manifolds and T fittings for all of the users, and attached these to the backs of the EFIS so they’re all handy.

New pitot/static tubing and fittings	New pitot connection
Installing Pitot Tube

In case you live under a rock, we’ve decided to get rid of our Blue Mountain Avionics EFIS/One (a generation 3 unit) in favor of the GRT system. A variety of factors played into this decision, which we didn’t take lightly. For one, I like and respect Greg as a person and engineer, and I really like the product generally. However there were features that we expected, based on statements by BMA, to be provided on our unit that were never delivered. Additionally, there have been occasional in-flight operational issues (the EFIS would roll 30 degrees to one side when the airplane was in level flight, as an example). Now BMA was willing to work with us to resolve the issues, and in fairness they felt the issue was with our powering certain sensors from the BMA board, but that was the recommendation at the time of my installation.

However, the main reason for moving away from the BMA is that we two fold. We felt that we should have been given better upgrade pricing to move to the Gen 4 system, since it contained features we felt we’d been promised. On top of this, many folks we know were still having issues with the new system, and were having trouble resolving them. On the other hand, everyone I’ve contacted about their GRT system has been very pleased with both the equipment and the support. On top of that, a Velocity friend of ours had an equipment failure with their BMA system and could not get a timely repair from them (they did not stock repair parts), so we opted to sell our unit to him. It was good for us, because we got some money out of it, and it got him back flying affordably. Another major factor was our little incident, which required me to pull all of the BMA sensor wiring out of the airplane so I could replace the oil tubes. I didn’t want to pull them all back in, nor did I want to pay for the $1k “engine pod” as I was less than satisfied with BMA overall, so I purchased the GRT EIS system for engine monitoring (with the intent of hooking it to our GRT Sport, which was our backup flight instrument at the time). These factors came together late this spring, and we opted to remvoe the sport and upgrade it to a dual screen, dual AHRS Grand Rapids Horizon HX with weather (small screens both on the pilot side). We will add a third (large) screen to the copilot side later, maybe as soon as Oshkosh. We’re also going to put in a half-panels worth of dial gauges to at least to the ground in VFR conditions should, God forbid, the EFIS go totally tango-uniform.

Here are some files related to our GRT installation that might be of interest to folks.
Serial Ports assignments and EIS configuration (fix link) Connector diagrams

Posted By: Brett Ferrell
Saturday April 3rd, 2010 at 2:43 PM

Categories: Instrument Panel Pitot/Static
Tags: Building GRT Horizon HX Instrument Panel Instruments Pitot/Static Stein