L-1011 Trainer Installation: EVAC Signal, FE Station Indicator Test

L1011 Trainer - FE Station Indicator Lights

Wow, today was a very productive day working on the Lockheed L-1011 trainer at the Museum. Today we completed the following work items:

1. Power up the indicator lights for the Fuel Jettison Panel 
2. Power up the indicator lights for the Engine Fuel Panel 
3. Powered the Brake Temperature gauge
4. Build and connected the Indicator Test Relay circuit for the FE Station
5. Installed and connected the L-1011 Evacuation Signal Panel
6. Jim installed some additional DIN rains into the overhead panel that will hold the future Interbus components

So lets start with the EVACUATION SIGNAL panel. The panel is used to initiate ground evacuation of the aircraft. The EVAC signal can be triggered from either the flight station (this is the panel we installed today) or from a Flight Attendant station (this will not be implemented in the simulator). The EVAC signal is pretty loud and would sounds from multiple stations throughout the aircraft.

L-1011 Trainer: Overhead Panel - Evacuation Signal

Below is a short video that shows the operation of the EVAC signal ad the "Horn Silence" momentary switch. You might want to turn your volume down a little on your computer before you play the video because the EVAC signal is pretty loud. By the way ... the signal is a 

Here is the schematic and pinout for the L-1011 Evacuation Signal panel:

L-1011 EVAC Panel Schematic from Delta L-1011 Training Manual

Besides the installation and power-up of the EVAC panel we also continued the indicator light buildout of the FE Station. Today we powered the Fuel Jettison panel indicators as well as the Engine Fuel panel indicators (see the two images below).

L-1011 Trainer: Fuel Jettison Indicator Lights

L-1011 Trainer: Engine Fuel Indicator Lights

The 5VDC instrument lighting buildout is also moving forward, while a bit slower due to the fact that we are waiting on additional 5VDC 20A as well as two 5VDC 40A power units to arrive. Below is the Brake Temperature indicator that we powered today. The indicator is a vertical tape instrument that shows two (left and right) selected brake assemblies at a time.

L-1011 Trainer: FE Station - Break Temperature Indicator

Lastly I build the indicator test circuit for the FE station. The test circuit turns on all indicator lights with a "TEST" switch on the FE Light Panel. The indicator test is implemented using a 24VDC relay.

L-1011 Trainer: FE Lights Indicator TEST Switch

The short video below show the operation of the FE Indicator Test circuit.

L-1011 Trainer Installation: Indicator Lighting Buildout

L-1011 Trainer Buildout: Indicator Lighting

Making small incremental steps with the buildout of the Indicator Lighting systems. The indicators (switchlights and annunciators) use circuitry and power sources independent from the cockpit instrument lights or the panel light plates. As we work through the indicator lighting build out we are also re-tooling the indicator lights from 28VDC incandescent lights to 24VDC LEDs. It's amazing how much that cuts down on heat produced in the sim, especially considering the fact that the L-1011 cockpit has hundreds of lights.

Once the progressive power-up of the indicator lights has completed we will start switching to connecting the switchlight and annunciators to the Digital I/O subsystems.

L-1011 Trainer Buildout: Fuel System Indicator Lights

L-1011 Trainer Installation: Overhead and FE Station Indicator Lights Build-Out

L-1011 Trainer Installation - Indicator Buildout

L-1011 Trainer Installation - Indicator Buildout

Continued with the indicator build out today. The Indicator light as well as the Indicator Test circuits are now connected to the FCES panel as well as portions of the Hydraulic and Engine Bleed Control panel The two images above illustrate which panels got connected during the most recent installation effort.

L-1011 Trainer Installation - Indicator Buildout

Below is a detail of the FCES and the PFCS panels. The FCES panel indicates status of the various Flight Control computer systems. Each switchlight has either an "OFF" or "FAIL" legend.

L-1011 Trainer Installation - Indicator Buildout

L-1011 Trainer Installation - Indicator Buildout (FCES and PFCS)

L-1011 Trainer Installation: Overhead Indicator Lights

L-1011 Trainer: Indicator Illumination - Overhead

Continued with the buildout of the overhead illumination today. Getting the PFCS Panel to work was a little bit of a head scratch. As part of the installation of the sim we are re-tooling all indicators from incandescent to LED lighting. LED's are, well just like the name indicates, diodes ... hence, they are directional. We initially replace all incandescent with standard midget-flanged LEDs ... however, it turns out that this is a problem. And here is why:

Since the L-1011 used 28V DC incandescent lighting it didn't matter if the "common" between the light bulbs inside a switchlight was connected to the 24VDC source or the DC Return ... the bulb would simply glow either way. But, with the LED this makes a big difference ... reverse the flow direction on the LED and it will not work at all .... because it's a diode.

Here is an example from the L-1011 WDM:

Here the common goes to the DC Return:

Here the common goes to 24V DC:

So here, Lockheed tripped me a little ... because I had not anticipated the switchlight light bulb polarity to be inverted between different panels or even within the same panel. Having learned this, we are going to have to get some LEDs with reversed polarity. That's not a problem, just something I had not anticipated. So, in the image above and below you can clearly see the difference in the LED lighting which is a clean white on the switch legend and the incandescent which has a much more yellow/red tone. 

L-1011 Trainer - Overheard Indicator Illumination (June 8th 2013)