Introduction

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This is a brief introduction to the story of my new instrument panel.

This is the panel before I put the plane into the shop. The plan was to put it in just after Thanksgiving, 2000, and get it finished in time for Xmas. As I’m learning is the norm for aviation, this didn’t happen. We bought the big avionics pieces, and those were wired up on the bench in anticipation of the arrival of the airplane. The equipment, (more or less) from left to right, top to bottom: stall warning indicator, clock, intercom, engine instruments, Piper Autocontrol II autopilot, pilot mic/headphone jack, airspeed, turn coordinator, vacuum, high/low vacuum warning lights, attitude indicator, heading indicator, trim switch, ignition, gear transit lights, altimeter, vertical speed indicator, engine instruments, manifold pressure/fuel flow, compass, VOR 1/glide slope, VOR 2, tachometer, gear switch, gear down lights, King audio panel, King KX-155 Nav/Com w/GS, King KX-155 Nav/Com, electrical switches, EGT, ADF, transponder, Narco DME, power port, CBs, environmental controls, co-pilot mic/headphone jack.
Here’s the panel after the installers pulled out everything. In the corner you can see part of the FAA FSDO inspector pointing at something. You can see that just about everything except the engine instruments has been removed.
This is a shot of test fitting a plastic version of the new panel. To do this, we removed the control yokes and detached the throttle quadrant from the panel (but we left the cables connected). What goes in most of the holes is what you’d expect. The basic six instruments are arranged in the standard pattern centered over the pilot’s yoke. You can see the attitude indicator and Sandel SN3308 holes on the left of the picture (the airspeed and turn coordinator are off the left edge of the photo). The five square holes in a row at the top of the panel are for the various indicator lights that were scattered throughout the original panel. They include the stall warning indicator, the vacuum high/low warnings, the gear-in-transit warning, and the gear motor indicator. This template represents an early layout. The latest layout has changed a bit.
This is the Garmin avionics stack going into the new panel. Pictured here are three separate components: the Garmin GMA-340 Audio Panel, the Garmin GNS 530 GPS/Nav/Com, and the Garmin GTX-327 Digital Transponder. The bundle of cables on the left of this stack runs to the Sandel SN3308 display pictured below. Some of those wires connect the Sandel to the GNS 530, and the rest run with the bundle to the right of the stack. That large bundle of wires connects to many other sensors, such as the altitude encoder and fuel flow monitor. It connects to several antenna: one for the GPS, one for the transponder, one for the Nav radio, and one for the Com radio. It also connects to the four headset and microphone jacks.
This is the Sandel SN3308. It is a primary flight display that replaces the conventional heading indicator. It uses a bright halogen light to project the graphics from a color LCD panel onto the front of the device. If you look closely, you can see that it shows a great deal more than simple heading information. It also shows the current flightplan and waypoints. Compare it to the display of the GNS530 above, and you can see the two displays are showing information about the same flightplan. The SN3308 also shows distance and bearing information, current ground speed, and nearby airports. Eventually, it will show other traffic and weather in the area.
Friday, Jul 6, 2001 The Arrow has been moved to Eagle’s Nest Aviation in Ukiah. After the previous installer blew up, Dan Leigh, the master mechanic who did most of the work, moved to Eagle’s Nest, and he took my plane with him (we figured it was a good idea to have the mechanic who did most of the work so far complete the work). I went up today to bring the piles of avionics and discuss the installation with Dan.
Friday, Jul 6, 2001 Everything has finally been pulled out of the old panel. We are going to start cutting it out on Tuesday, although we might wait for approval and cut the whole thing when we get it. The plan is to use an electric hack saw to cut around the top perimeter of the old panel, leaving 0.5" - 0.75" of old panel in place. The new panel will be mounted with screws to this. The horizontal silver u-channel in the picture is being replaced with a new 0.100"-thick 5052 aluminum channel fabricated, along with the panel, by Avion Research. Because this replacement involves a structural modification to the aircraft, a Form 337 needs to be sumbitted to the FAA for approval.
Friday, Jul 6, 2001 One of the com antennae had to be moved rearward to make room for the GPS antenna, which needs 3 feet all around clear of other antennae. The com antenna is surrounded by a perimeter of new rivets which hold a doubler, a patch of aluminum used to stiffen the point on the hull where the antenna is attached. The green patch under the GPS antenna is primer that will be painted before the installation is complete. The GPS antenna was placed in the com antenna's old location.
Friday, Jul 6, 2001 This is a shot of the interior of the tail section. The blurry black box in front is the battery box. Just behind that you can see the top of a black cylinder, and numerous cables connecting to the control surfaces of the empennage. The black cylinder is (I think) the King remote gyro, which will drive the Sandel SN3308 heading information.