Showing posts with label N2. Show all posts
Showing posts with label N2. Show all posts

Monday, July 22, 2013

L-1011 Trainer Installation: %N2 Instrument Power-Up - 400Hz Power System Validation


The short video clip above shows another set of instruments now connected to the 400Hz power distribution system. By the way, we finally found a third %N2 RPM indicator that should arrive at the museum shortly so that we can finally replace the fake one we still have in place for Engine 3. What you see in the video is the instrument self test, or BITE (Built In Test). In the case of the %N2 RPM indicator the BITE will drive the instrument to 91% RPM N2.

By the way, one day I will learn how to operate instruments and hold the camera more steady at the same time!

Below is the description of the %N2 Tachometer taken from the Delta's Pilots Reference manual for the Lockheed L-1011.

L-1011 %N2 Tachometer - from Delta L-1011 Pilot's Reference

Wednesday, July 3, 2013

L-1011 Trainer Installation: MIP and FE Station Instrument Lighting

L-1011 Trainer: Instrument Lighting Build-Out (FE Station)

Today we continued the build-out of some of the integral instrument lighting on the FE station as well as the main instrument panel. On the FE station we connected the Engine %RPM N2 instruments as well as the Slat Monitor / Slat Position Indicator. All the instruments use 5V power and are driven from either the FE Station Lower Right Light Bus (for the %N2) and the FE Station Upper Right Light Bus (Slat Position).

During the connector installation we discovered that the FE station used for the trainer has a metal plate right behind the Slat Monitor that prevented the connector from mating correctly with the instrument. Therefore, we had to make a panel configuration change and move the Flight Engineer's Annunciator Panel into the position of the Slat Monitor and moved the Slat Monitor down.

L-1011 Trainer: FE Station Instrument Lighting and Door Annunciator

We don't think that this configuration change is going to make a significant difference to the authenticity of the L-1011 cockpit, however, one of the %RPM N2 instruments is still one of the original simulated procedures trainer instruments. Need to replace it with the real flight hardware as soon as I can find one.

L-1011 Trainer: FE Station %N2 Instrument Lighting

Last week we had started powering up the instruments on the pilot's center instrument panel. This is the place where the majority of the engine instruments are located. The instruments are split into two 5V light buses: Captain's Center Instrument Left and Captain's Center Instrument Right. The instruments that you can see illuminated in the picture below all belong to the Center Instrument Right light bus. During the initial build-out session we discovered that we did not have the right connectors for the Engine EPR instruments ... hence, we could not connect them ... we missed three Deutsch 15-S7 connectors. We now have them (those guys are hard to find and expensive) but we finally got them. So now all the instruments belonging to this light bus are connected.

L-1011 Trainer Build-Out: Main Instrument Panel Engine EPR Instrument Lighting

Sunday, August 14, 2011

Avionics Bending: N2 Tachometer - Pinout


The N2 %RPM indicator on the L-1011 is not located on the center panel, but on the flight engineers' engine status panel.



Unlike the tachometers on the pilots center panel, the N2 for the flight engineers does not have a digital readout ... it only has a pointer. However, the basic instrument principle of it being driven by a phonic wheel attached to the N2 compressor stage still applies. Below is the schematic for a General Electric %RPM N2 Indicator:


Here is the pinout:


ConnectorPinFunction



J1 01 5VAC/5VDC Instrument Lighting (Hi)
J1 02 5VAC/VDC Instrument Lighting (Lo)
J1 03 Tachometer Signal Twister Pair Shielding Ground
J1 04 Frequency Limit Elect - Ground
J1 05 115V 400Hz Power Supply (Hi)
J1 06 Tachometer Input TP - B
J1 07 Tachometer Input TP - A
J1 08 Casing Ground
J1 10 Over Limit Switch (Input)
J1 11 Over Limit Switch - Ground
J1 12 Frequency Limit Elect - Input
J1 13 AIDS Buffer Output
J1 14 115V 400Hz Power Supply (Lo)
J1 15 Frequency Limit Elect - Ground

Thursday, September 2, 2010

System Description by Don Pierce: Engine Status and Engine Oil


ENGINE STATUS Panel:

The top row of indicators are the N2 indicators, showing N2 speed. They are round dial instruments on all L-1011s, even though some planes have vertical tape instruments for N1 and N3. It is normal for the FE to call out beginning of N2 rotation during the engine start process.


The second row if indicators are the Vibration Monitor Indicators. They read from 0 to 5 units of vibration. Each indicator has a BITE button which will drive that respective indicator to approximately 4.0 units, verifying indicator operation. Also. each indicator has an amber light that illuminates about about half-scale (2.5 units) At the same time a light will illuminate on the pilots' caution and warning panel. The reading of the light varies - it might be ENG VIB/FLTR PRESS or ENGINE/APU STATUS.

Below the indicators are a series of test-related switches. The TEST push-button switch is used to test the signal conditioner (located in the MESC) and all three indicators. Pressing and holding the switch will cause all three indicators to read approximately 4.0 units; the amber lights will illuminate when the needles of the indicators pass about 2.5 units. When the switch is release, the indicator will return to 0 units (assuming the engine is not running) but the light remains "on", if the needles had passed 3.0 units when the needle was "rising". To extinguish the lights, the TEST switch must be pressed a second time (briefly).

The A and B latching switchlights provide the capability to select either of the two vibration pickups. When both switchlights are unlatched, both pickups are sampled, every 0.5 second. Note: the reading for the switchlights may be FAN and TRUB - for an earlier configuration; location of the vibration transducers will also vary. The ON light is switchlight position.

The four-position rotary switch is a "filter selector". When the switch is at the NORM (normal) position, the rotor frequency being monitored is the frequency range of all three rotating assemblies. When the other three rotary switch positions are selected, the frequency range is of one of the three rotors being monitored: LOW is the LP shaft (N1), MED is the IP shaft (N2) and HIGH is the HP shaft (N3). Note: The level of vibration being seen depends on the "age" of the engine.


ENGINE OIL Panel:

The engine oil QUANTITY indicators have a units display that varies from airline to airline; the quantity also varies, depending on type of engine.

Below the QUANTITY indicators are three oil TEMP indicators, in °C. All six of these indicators each have a small BITE button that is used to test the respective indicator. Faceplate light access for all six indicators is via the front of the indicator. All six instruments are made by General Electric.

Next are three oil PRESS (pressure) gages, manufactured by Smiths Industries. The range of the gage is 0 to 100 psi, in increments of 5 psi. The range is red from 0 to 35 psi, then yellow from 35 to 40, and green from 40 to 100 psi. The three pressure gages have a single, common TEST switchlight. There are three OIL PRESS ENG (x) lights on the pilots' caution and warning panel, which illuminate when the associated engine's oil pressure is too low.

The three amber FILTER PRESSURE lights illuminate to show an excessive pressure drop across either the associated oil pressure filter or the associated fine oil scavenge filter. At the same time, the ENG VIB/FLTR PRESS light on the caution and warning panel will illuminate. This light was also discussed (above) along with Engine Vibration.

Wednesday, November 4, 2009

Original Flight Hardware: Engine Cluster



The Lockheed L-1011 has an awesome engine cluster. It is home to the EPR, N1, EGT, N3 and FF gauges. In the picture above, you actually see instruments from a Boeing 747. I chose the B747 instruments because the will be easier to automate and control with the flight simulator software.





Another deviation from the standard L-1011 engine cluster that you might have noticed by now is that I, for now, substituted N2 gauges for the L-1011 N3 gauge. The reason being that the N3 gauges are pretty difficult to find. However, it does not mean that I will not replace the B747 N2 gauges with N3 gauges that better fit the 3 compressor stages of the L-1011 engines.



As you can see from the picture above, there are quite a few things still missing from the center panel. I don't have any of the standby instrumentation ... which will hopefully come soon.

Panel Location


L-1011 flight station picture used with permission from Sam Chui. Retrieved from airliners.net