History: Eastern Airlines L-1011 (Ship 309 and 334)

Eastern L-1011 (C) Enid Grigg

Enid Grigg has a number of really nice shots of Easter Airlines L-1011s that she took when she worked on the L-1011 in 1979. Enid is an awesome photographer and I appreciate her allowing us to put these beautiful black and white pictures up here on the blog.

Eastern L-1011 (C) Enid Grigg

The image below gives you a pretty good idea just how spacious and L-1011 cockpit is.

Eastern L-1011 (C) Enid Grigg

 One thing that is very consistent are the stories from people who worked on, flew or maintained the L-1011: it was a truly awesome plane to fly on. The picture below shows the underfloor galley. Richard pointed out that you can see that this picture would have been taken during flight and during service because the first three meal carts on the right hand side (foreground) are facing backs out indicating that they are empty or had been used. The other carts in the back are still plugged in (coiled cord on top) to keep the meals warm. Above the carts are the galley ovens and above the ovens are the refrigerators.

Eastern L-1011 (C) Enid Grigg

Below the very spacious and elegant first class cabin in the L-1011.

Eastern L-1011 (C) Enid Grigg

Now for a few cockpit shots. The Eastern Airlines L-1011s had been configured with tapes for the engine instruments. This is a distinct difference for the L-1011s used by Delta. Delta configured the engine instruments as round instruments to keep a familiar instrumentation environment for it's Pilots. 

Eastern L-1011 (C) Enid Grigg

Eastern L-1011 (C) Enid Grigg

Eastern L-1011 (C) Enid Grigg

Another distinct feature of the Easter L-1011 is the configuration of the weather radar screens in to the main instrument panel. While placing the radar into the MIP was not uncommon, it was later configure further over the the side into the chart panel.

Eastern L-1011 (C) Enid Grigg

Eastern L-1011 (C) Enid Grigg

Images used with permission granted by Enid Grigg. 

Avionics Bending: Aural Warning Unit

L-1011 Aural Warning Unit

The L-1011 has a set of somewhat very distinct cockpit sounds. The sounds are created by an "Aural Warning Unit" located right underneath the second officer console. Finding this unit in L-1011 surplus and scrap was not particularly easy however, I got my hands on one that is in really neat shape and is an original L-1011 unit. The serial number on the unit is #160 so it's from somewhere out of the middle of the production run. The Aural Warning Unit produces audible alerts for:

• Unsafe Landing 
• Unsafe Takeoff 
• Cabin Pressure 
• Altitude Alert
• Flap Load Relieving 
• Overspeed Clacker
• Autopilot Disconnect

The following video lets you hear the different audio warning (caution, this is somewhat loud ... you might want to turn your speakers or headphones down a little)

The unit features two speakers ... there are actually two audio systems in the unit the Clacker has a discrete speaker and the rest of the oscillator driven warnings have their own speaker.

L-1011 Aural Warning Unit Speakers

L-1011 Trainer Installation: Fuel System Panel

L-1011 Trainer: Fuel System Panel

In this posting I conducted some tests with the Lockheed L–1011 fuel system panel. 

The image above shows the Lockheed L–1011 Fuel System panel illuminated in switch light test mode. Many of the system panels have a test input that allows for quick illumination of all of the switchlights and annunciators on a single panel. 

The image below shows a typical panel configuration when sitting at a parking position with let's say only the engine 2 running. 

L-1011 Trainer: Fuel System Panel

Below is the pressurized fuel flow path from Tank 2R to Engine 2 marked with the dashed orange line:

L-1011 Trainer: Fuel System - Tank 2R Fuel Pressure to Engine 2

Also, as I am bringing these panels online I am switching them from incandescent to LEDs. The LEDs help return the yellowed switch light lenses back to white.

L-1011 Trainer: Fuel System Panel LED Replacement

In the image above the Tank 1 Pump number 2 has been converted to LED lighting.

L-1011 Trainer: Generator Breaker Buildout

L-1011 Trainer - Power System Buildout

Work on the power system for the L-1011 continues. Yes, this has taken quite a while but getting the power system right is somewhat the foundation for the entire simulator, especially, creating the systems to work in a way that they act realistic.

In the previous posting I showed you the AC Tie Bus buildout. Today, we continued to work on the generator breakers. There is a power generator breaker for each on-board generator (APU, ENG1, ENG2 and ENG3) that is used to power its respective power bus. The APU is switched directly onto the AC Tie bus while the ENG1, ENG2 and ENG3 generator powers the respective AC Bus1, AC Bus 2 and AC Bus 3. Each AC Bus can be tied onto the AC tie bus to form a combined and highly resilient power system. 

The image below shows the row of four (4) generator breakers with APU, ENG1, ENG2 and ENG3 from left to right.

L-1011 Trainer - Power System Buildout - Generator Breakers

Next, let's look at a number of examples showing how the AC Tie bus can be powered from different sources. By the way each AC Bus also drives a Transformer Rectifier (T/R) that supplies the aircraft's DC system with power. 

In the following images solid yellow lines indicate AC power and dashed yellow lines indicate DC power. 

Example 1: Aircraft Powered from External Power Source

So here we could be at the gate with power coming from the ground power connector or we could be pulled off somewhere into a parking position powered by a ground cart.

L-1011 Trainer - Power System Buildout - External Power on Bus

You see the green "AVAIL" light indicating that External Power is available an the "ON" light above it indicating that we selected the toggle switch to "on" and that the external power got switched directly onto the AC Tie bus. All three AC Tie Bus Breakers are closed as indicated by the white flow bars. The image below shows the power flow.

L-1011 Trainer - Power System Buildout - External Power Flow

Example 2: Aircraft Powered by Engine 2 Generator

In this example (which is not so typical) we would still be connected to a ground cart or external power (green AVAIL light) however, the external power is not switched onto the bus. Instead, we are powering the AC Tie bus with power coming from the #2 engine generator. In this case, of course, engine two would be running and producing power.

L-1011 Trainer - Power System Buildout - Engine 2 Generator Power on Bus

The image below shows the power flow from the engine #2 generator to AC Bus 2 and because all three AC Tie Bus Breakers are closed we are also powering all the remaining buses from the engine 2 generator.

L-1011 Trainer - Power System Buildout - Engine 2 Power Flow

Example 3: Aircraft Powered from APU

In the final example we see a typical scenario of an aircraft that has either just pulled up to the gate or is about to leave the gate. Here we have switched from External Power (or Ground Power) to the APU. You can see that the APU generator breaker (top left) has been closed and is providing power directly to the AC Tie Bus. Closing the APU Generator Breaker would have automatically tripped the External Power selector from the "ON" to the "OFF" position since APU Power and EXT Power can not be phase synchronized.

L-1011 Trainer - Power System Buildout - APU Power on Bus

The image below shows the APU Power Flow with all three AC Tie Bus Breakers closed.

L-1011 Trainer - Power System Buildout - APU Power Flow

L-1011 CPT Installation: External Power and AC Tie Bus

L-1011 CPT - AC Tie Bus Relays

Today we installed the AC Tie Bus relays as well as the EXT PWR relay. The image above shows the AC Tie Bus control relays together with the APU, ENG1-3 and EXT PWR control relays prior to installation into the trainer.

The control relays are all Phoenix Contact 24V DC relays and in turn control the annunciator lights on the Electrical System panel as well as the the power relays in the DC/AC power distribution rack. Below is a short video of the operation of the External Power and the distribution of external power across the AC Tie Bus to the individual AC buses and the flight station power buses.

In case you don't want to watch the video. Here are a few still that first show the AC Tie Bus un-powered with AC External Power "AVAIL" (Available) but not ON.

L-1011 CPT - AC Tie Bus Open

Below the External Power is not switch onto the AC Tie Bus, the three Tie Bus Breakers are closed and AC BUS 1, 2 and 3 are now powered.

L-1011 CPT - Ac Tie Bus Closed and EXT Power ON

The lower FE/SO Station integral instruments light are powered by transformers connected the to AC Flight Station Bus 2. Int he picture below you can see that the instruments illuminate with External Power ON and only the AC BUS 2 tied to the AC Tie Bus.

L-1011 CPT - AC BUS2 Joined To Tie Bus Only

Below is a 2nd short video showing the operation of bringing AC BUS 2 online via the AC Tie bus only.

L-1011 CPT Installation: DC System Buildout - Integral Instrument Lighting FE/SO Station

L-1011 Trainer - Integral Instrument Lighting Buildout

Continuing with the Instrument Lighting build-out on the lower FE/SO Station. We now have almost the entire instrument cluster on the FE/SO Station connected to the FE/SO Lower Right instrument light bus. The only three instruments that are remaining are the %N2 Tachometers at the very top of the instrument cluster. (Currently only 2 of the 3 are real flight hardware, I am trying to get the 3rd one but I keep getting outbid on eBay).

Below is an image that better illustrates the instrument illumination work for the FE/SO Station Instrument Cluster.

L-1011 Trainer - Integral Instrument Lighting Buildout

All instrument integral illumination on the lower FE/SO Station is powered via two Circuit Breaker by a Lambda 5V 20A power supply. The incandescent lamps in the instruments consume a total of about 16A when fully built out. An identical 5V 20A power supply will drive the upper FE/SO Station integral instrument lights.

L-1011 Trainer - Integral Instrument Lighting Buildout

Light Plate illumination is going to be next and will require a 5V 40A power source to drive the light plates on the S/O station. Once the integral instrument lighting on the FE/SO Station is done we will move on to the Captain's and F/Os instrument lighting. 

Avionics Bending: Honeywell CD-800 Display Unit

Honeywell CD-800 Display Unit

Every now and then I need to take my mind off the L-1011 for a moment and go play with something totally different. Today I powered up a Honeywell CD-800 Display Unit. They are pretty neat little terminal units most frequently used on Gulfstream business jets and would be connected to something like a Honeywell NZ-920 Navigation Computer. While it is not totally unrealistic that such an avionics package could have been installed on the L-1011 I have not found any evidence that it was ever considered. The FMS on the L-1011 typically consisted of, for example, a Litton INS. However this unit is still a lot of fun and has a lot of ARINC 429, RS424 and RS232 inputs and it might become a good fit for the next project, the MD-83 project.

The CD-800 Control Display Unit (CDU) is the pilot interface with the FMS. The CRT displays relative flight information to the pilot. The pilot enters alphanumeric data into the system via the full alphanumeric keyboard. This data appears in the scratchpad to be line selected to the appropriate position on the CRT display. (from Honeywell Maintenance Guide)

Honeywell CD-800 Annunciators

Annunciators - The six annunciators located at the top of the CDU keyboard panel operate independently from the CRT and keyboard. Lighting of the annunciators is initiated by the navigation computer or performance computer via the RS422 serial data link. The two colors used for annunciations are white and amber. White indicates an advisory type annunciation, and amber indicates an alerting type annunciation (810 and up only). (from Honeywell Maintenance Guide)

Honeywell CD-800 Without Navigation Computer

Here it the block diagram for the unit:

(from Honeywell Maintenance Guide)

L-1011 CPT Installation: FE/SO Station Instrument Lighting - Buildout

L-1011 Trainer - Electrical System Panel

Today we continued with the work on the instrument lighting buses. The FE/SO station has four segments that make up the lighting bus fort he integral instrument lighting. The image below shows how the integral instrument lighting for the FE/SO Station is split over tow breakers located on the CB3 panel. The instruments on the lower left and the instrument on the lower right (as indicated) belong together and make up two segments of the instrument lighting bus. Further, each light plate on the FE/SO console has a discrete circuit breaker. The image above shows the 3 light plates that make up the Electrical System panel illuminated.

L-1011 Trainer - Integral Instrument Lighting Buildout

The L-1011 can be powered with external power while on the ground. When external power is connected to the aircraft the green "AVAIL" annunciator illuminates on the lower left hand side of the electrical system panel and a hold solenoid is activated for the switch. When the switches is moved to the "ON" position the external power is directly connected to the AC Tie bus and the "ON" annunciator illuminates. The ON/OFF switch will release back to the "OFF" position when the hold solenoid is disconnect; the disconnect happens when either the external power is disconnected or another on-board generator (APU, or Engine) is being brought online.

L-1011 Trainer - External Power

 Below is a picture of the current state of the FE/SE Station buildout. The goal is to complete the integral instrumentation buildout over the next few days and then to move on to the light plates. By the way, each of the instrument and plate illumination systems is powered by a Lambda 5V 20A power source.

Avionics Bending: Percent N3 Tachometer Indicator

L-1011 %N3 Tachometer - RB.211

For today's avionics bend I am going to show you the %N3 Tachometer. The RB.211 is a three spool engine and therefor there is a %N1, %N2 and %N3 tachometer present in the L-1011 cockpit. The %N1 and %N3 tachometers are part of the engine cluster on the center main instrument panel. The %N2 tachometer is part of the engine cluster on the Flight Engineers station. The %N3 tachometer works pretty much just like the %N1 and %N2 tachometers in that they take a frequency and coverts it to a needle position as well as a digital readout (bottom of the instrument). Here is the schematic for the %N3 instrument:

L-1011 %N3 Tachometer Schematic and Pinout

What makes the %N3 tachometer different from the %N1 and %N2 tachometer is the fact that the instrument plays a pretty critical role during engine start up. To be more exact, it controls the duration of bleed air being supplied to the air-start motor on the engine.

Below is a picture of the Ground Start Switchlight for Engine 1:

The magic inside the %N3 instrument (on the left) happens during the engine start up and once the 3rd compressor stage has spooled up to 52% N3 with the air-start motor. Here is what happens 

The GROUND START switchights are solenoid held, and are latched in to initiate the start . This gives a command to open the associated start control valve to allow air (from the APU, another engine, or a ground cart) and begin the rotation of the compressors. The green VALVE OPEN light illuminates to indicate that the associated start control valve is NOT CLOSED. Once the %N3 Indicator reaches 52% the Ground Start switch for that engine is released and the valve closes. At this point the engine runs on it's own.

Here is a demo video of the %N3 action and solenoid held switch release: