Script Document

Safety Systems Aircraft Lighting Script Writer: Roshan P. Bhojwani

Lesson Introduction Welcome to the PMDG 777-200LR Aircraft Lighting Groundwork lesson, from Angle of Attack. Today in this lesson we are going to run through all the different types of exterior and interior lights that the 777 carries on board. All aircraft are required to have forms of lighting by regulations, and it is nice to think that each of them have a meaning and purpose. That is why we are going to look at each set of lights that brighten up the 777 in detail. The main groups we are going to cover today are:

- Exterior lighting, - Flight deck lighting, - Cabin lighting, - Emergency lighting.

Lets start with the first.

Exterior Lighting Exterior lighting in the 777, and in all aircraft actually, is used to alert the presence of the aircraft as well as portray the aircrafts position with regards to other traffic on ground, or in the air. By other traffic we mean not just other aircraft, but also other crews, ground handling staff, other passengers, and basically anybody that could be a hazard to the aircraft should they not be able to recognize it properly. Take a look at all the different exterior lights on the 777 as they are highlighted in the diagram. We have:

- Four landing lights, - Two taxi lights, - Two anti-collision beacon lights, - Three anti-collision strobe lights, - Five navigation lights, - Four logo lights, - Two runway turnoff lights, - Two wing lights.

Lets focus in on landing lights first. Landing Lights Landing lights correspond to four strong beams emitted from the aircraft forward, to illuminate the ground area ahead of it during takeoff and landing. There are two landing lights on the nose landing gear and two wing landing lights, one on the left wing root near the wing-to-body fairing, and the other in the right wing root.

Script Document

Safety Systems Aircraft Lighting Script Writer: Roshan P. Bhojwani

All four landing lights are angled differently. The left and right main landing lights are angled to aid the flare during landing, and ground roll once the aircraft has touched down or is taking off. The nose landing gear is slightly tilted downward to maximize forward vision during the approach. Remember that during approaches the aircraft is exposed to relatively high thrust settings, low airspeed and high angles of attack, meaning the normal approach attitude is a few degrees nose-up. The LEFT, NOSE & RIGHT landing light switches control landing light operation. When the switches are ON, landing lights are illuminated, contrary to when the switches are OFF. Note that the nose landing light will only illuminate if the nose landing gear is down and locked. Taxi Lights Taxi lights work similarly to landing lights, except that there are only two and they are of much lesser intensity. Both taxi lights are located in the nose gear strut. Even though the nose gear is fully steerable, the taxi lights are mounted in a part that is not. They are only used during taxi to illuminate the taxiways ahead of the aircraft, and only operate when the nose gear is down and locked. Taxi lights are controlled with the TAXI light switch, having two self-explanatory positions: ON & OFF. Anti-collision Beacon Lights Anti-collision beacon lights, or simply beacons, are two smaller red lights that flash simultaneously at 48 flashes per minute. One is located in the aircraft upper body, above the fuselage, and the other is located below the fuselage. Beacon lights are extremely important, and must remain on whenever the aircraft is in ground or flight operation. Beacons normally symbolize caution, as the aircraft may be in movement and the engines may be turned on. Anti-collision Strobe Lights Similar to the beacon lights, are the anti-collision strobe lights, or simply strobes. These are three very strong white flashing lights located one on each wing, and the third in the aircrafts tailcone. They flash simultaneously at a rate of 48 flashes per second, but are synchronized so that their illumination is alternated with that of the beacon lights. Strobe lights are extremely important as they allow aircraft to be seen better during the night time, or low visibility operations. Because the lamps are so strong, it is important that these are not turned on during the taxiways, or any other movement area of the airport other than the runways, as injury to people may be caused. Strobe lights are operated with the STROBE light switch in the overhead panel, which has two self-explanatory positions. Position Lights Now, following strobe lights, we are going to look at position lights. These are also commonly known as navigation lights. The aircraft has five navigation lights. One of them on the left wing is of red colour. The other one on the right

Script Document

Safety Systems Aircraft Lighting Script Writer: Roshan P. Bhojwani

wing is of green colour. Behind the wing navigation lights there are two white navigation lights immediately aft of the wing strobe lights. The last navigation light is found in the aircrafts tailcone and it is of white colour. This colour structure is used so that when the aircraft is flying, other aircraft can recognise it from the air and estimate its relative position from them, as well as determine its approximate heading. Many ships and some trains also use the same navigation lights system for the same purpose. All five navigation lights do not flash at a given rate like the anti-collision beacons and strobes, instead they are constantly illuminated whenever the respective switch has been turned on. Navigation lights are operated with the NAV light pushbutton in the overhead panel. Logo Lights Moving on with logo lights. These are not primordial for safety but are worth discussing anyways. Logo lights are located on the horizontal stabilizer leading edges and are pointed upwards to illuminate the vertical portion of the stabilizer, where the airline logo is found. Logo lights are operated with the LOGO light pushbutton in the overhead. Pushing the switch turns the lights on. Runway Turnoff Lights Next stop, runway turnoff lights. These are a set of lights, each located on each wing-to-body fairing that illuminate the area in front of each main gear, so that the crews can see the runway and taxiway turnoffs during the night time and low visibility operations. Runway turnoff lights are operated with the L & R RUNWAY TURNOFF light switches, with ON and OFF positions. The ON position obviously turns the related light on, and the OFF position extinguishes it. Wing Lights And finally, we have wing lights. Two wing lights are available, located immediately next to each runway turnoff light. Wing lights are not always used, however they have a very important function. They illuminate the leading edge and engine nacelles of both wings to allow crews to inspect for any possible icing formation. Remember that icing on the wing leading edges greatly alters the wings aerodynamic profile, restricting its capacity to produce lift and greatly increasing the drag it produces. The WING light overhead switch is used to operate the wing lights. Note that unlike the runway turnoff lights, there is only one wing light switch that controls and operates both wing lights. Operation of all the lights weve talked about is described in the PMDG 777 documentation, however you should expect to get a better understanding of when to turn each one ON or OFF according to the respective flight phases when you begin your Flightwork training.

Script Document

Safety Systems Aircraft Lighting Script Writer: Roshan P. Bhojwani

Flight Deck Lighting Now that weve talked about exterior lighting, its time to jump into the flight deck and have a look at the series of lights that allow pilots to read without difficulty during the night time. Flight deck lighting is provided to take charge of the following tasks:

- Give general ambient light, - Give light to display panels, - And illuminate system indications.

To do this, the flight deck has three main lighting sections:

- Flight deck illumination, - Integral panel lighting, - Flight deck miscellaneous localized lights.

Lets start with the first: flight deck illumination. Dome lights provide the required ambient light for the flight deck.. There are two dome lights, one above each pilots seat. To operate dome lights, the DOME light control in the lighting overhead panel must be rotated, and the light intensity results as a function of the dome controls position. Normally the brightness is adjusted with this controller, however during operations where the right AC transfer bus, or the ground service bus is not energized, the dome lights enter standby mode and illuminate at a fixed rate. Moving on, we have the integral panel lights, which give light to the controls and indications on display panels in the flight deck. Panel lights, along with flood lights, illuminate the forward panels, glareshield and aisle stand. Similar to dome lights, when electrical power is lost, aisle stand, left and forward panel and glareshield flood lights all illuminate with standby electrical power. And lastly the miscellaneous lights, which illuminate general areas. These are chart lights, floor lights, and worktable lights. Most panel lights can be bypassed by either of two means: one of them is the master brightness control system. The master brightness control system allows control of all lights with one single control. When the MASTER BRIGHTNESS switch is pushed ON, the control is activated. These are the following lights that come under the master brightness control system:

- Forward panel lights, - Glareshield panel, - Overhead panel,

Script Document

Safety Systems Aircraft Lighting Script Writer: Roshan P. Bhojwani

- Digital displays, - Standby instruments and compass, - Clocks, - CDUs, - EICAS - MFDs, - and PFDs.

Whenever you want to adjust an individual light when the master brightness system is operating, the related light switch allows for a tiny change in brightness, but this change is significantly lower than the normal full brightness range of the switch. The other way to bypass normal flight deck lighting is with the STORM light pushbutton, also located in the overhead lighting panel. What the storm light switch does once it has been turned ON, it overrides all normal lighting controls and illuminates the following series of lights at maximum brightness:

- Both dome lights, - Aisle stand flood lights, - Instrument panel flood lights, - Glareshield flood lights, - All illuminated indicator lights.

Cabin Lighting Now for the next little section of this lesson, cabin lighting. Mainly, cabin lighting is not a concern of the flight crew, as cabin crew is responsible for operating and selecting the different required levels of lighting during the various flight phases. There is a point of concern for flight crew, or pilots, though. Cabin lighting near the flight deck entry door is automatically dimmed whenever the flight deck door has been opened and either aircraft engine is running. This logic is there so that the light level immediately outside the cockpit is reduced and pilots entering or coming out of the cockpit can make an easier visual transition into the new lighting condition, thus minimizing the risk of dizziness or any other unwanted condition. Thats pretty much it for the PMDG 777 cabin lighting section. Obviously theres a lot more to it, but it is not of primary importance and well leave you to read the PMDG documentation and learn about it.

Script Document

Safety Systems Aircraft Lighting Script Writer: Roshan P. Bhojwani

Emergency Lighting For the last section of this lesson, which is emergency lighting, you should know that whenever the aircrafts DC electric power system is faulty or it has been turned off, the emergency lighting system comes automatically into action. Remote batteries provide energy for emergency lighting. The charge for these batteries is maintained by the aircrafts electrical system, transforming AC to DC power. A full charge of these batteries will allow around 15min of emergency lighting operation. Emergency lighting is assigned by either of two ways, from two different locations. One one hand, the flight attendants may select and activate emergency lighting should there be any need for it. On the other hand, flight crew in the cockpit can select and activate emergency lighting. This is done with the guarded EMER LIGHTS switch, which has the following positions:

- OFF: prevents emergency lights to power up even if the DC power system loses power and/or is turned off.

- ARMED: illuminates all emergency lights whenever the aircrafts DC power system loses power and/or has been turned off.

- ON: when the switch is commanded on, all emergency lights illuminate irrespective or DC power status.

Lesson Summary This lesson covered a range of aircraft lights and their respective switches. Weve had a look at external lights including: strobes, beacons, navigation, wing, logo, taxi, runway turnoff and landing lights. Next stop, flight deck lighting. We talked about dome lights, flood lights and instrument localized lighting. We also talked a tiny bit about cabin lighting, emphasizing that ambient light around the flight deck is normally dimmed when the aircraft is running to aid the transition of pilots eyes in and out of the flight deck during low-light or night-time operations. And finally, we discussed emergency lighting from an operational standpoint. All forms of lighting do not have very extensive theoretical backgrounds to them, which is why you should stay tuned to the 777 FlightWork sections which will clearly show you how and when to operate each form of lighting, as well as which one has a nominal priority over others. Thanks again for watching, stay tuned to the following lesson in the Safety section. Until then, Throttle On!