Hello! First off.While reading about the Electrical Power Up procedure the FCOM I noticed the item "Wheel well fire warning system.......................Test" and I can't find this test switch.Can anyone tell me what this item wants the flight crew to do? Secondly.The amplified procedures never ask the flight crew to extend and switch on the retractable landing lights. When are the retractable landing lights supposed to be used? Thanks in advance!

Wheel well fire test is on the left upper pedestal behind the thrust levers, IIRC.

Just do the normal fire test procedure, and you should see the wheel well fire light come on. It's where Zach says it is. At least, that's what i do.

Wheel well fire test is tested the same time as the engines and APU, normally. However, if you don't have ground power and you haven't started the APU, you won't have A/C power. Guess what power the wheel well needs - A/C. So, you need to test the APU fire warning before you turn it on. That's on D/C. Test it, start the APU, bring the APU GEN online, and then test the fire warning again, this time making sure you have the wheel well fire warning tested.Retractable landing lights usage varies from company to company. Some companies have them on when cleared for T/O some when entering the runway. Some turn them off at 10,000' or above 250kias or FL180. Simple way: on entering the runway, off at 10,000. On again at 10,000, off exiting the runway.

Alright, I get it now. Thank you for your help guys! :)

Fire and overheat sensors/boxes are powered by 28VDC as they are responsable of the safety of the plane.Fire squibs are powered directly from Hot battery bus, so they works also if the aircraft is switched OFF.Tat is needed because if we have engine shut down then lose another generator plus the APU inoperative (a really bad day) and we have a fire, we must know! If it is an overheat of the bleed ducts we must know, this will let us to switch off a bleed, to use fire handle for an engine fire, to extinguish a fire in the cargos.All those things are very danger for the plane, smokes, fire, all possible causes of death, they must work as far as they can.

Retractable landing lights are typically for the climb and descent parts of your flight where speed is below 250 knots since their retraction mechanism will be damaged at speeds very much higher than that, so passing 10,000 feet is often the trigger for a crew to extend/retract them. They are not actually mandatory for all circumstances, although obviously when you are getting near to an airport they help with making you conspicuous and most crews will use them because of that. At night they do light up clouds a lot as you pass through, so that as well as the lamp itself and the clouds they illuminate are a big aid to avoiding conflicts. In real life one should consider retracting them if one suspects the runway is contaminated with stuff that is likely to fly up and damage them, as they are certainly not indestructible and can be smashed or even jammed by flying stones and such (Boeing and other aircraft manufacturers often toy with the idea of locating them in various new spots on the airframe to avoid such damage from debris, and they did in fact used to be in a different place on earlier 737s), but of course in a flight sim such damage is an unlikely occurrence, although you would be simulating more realistic operations if you kept them retracted when operating from rougher airstrips. So the answer really is, use the landing lights when you think it would be sensible to do so based on all of the above.

Wheel well fire test is on the left upper pedestal behind the thrust levers, IIRC.

Is this modeled in PMDGNGX?I see it in Michael Swannick's 737NG -800 checklist but I did not see it in the VC throttle view.

Is this modeled in PMDGNGX?I see it in Michael Swannick's 737NG -800 checklist but I did not see it in the VC throttle view.

It's there!

Just curious, where?

I read here, Note: but this switch name "wheel well fire test" is not upper left pedestal behind throttles???:http://www.b737.org.uk/ngata26.htmThese are the indications of a wheel well fire:-A] P7 Fire warn light comes on.B] P8 Wheel well light comes on.C] Aural warning unit gives a bell sound.D] MAINT ADV light comes on.Push the P7 FIRE WARN lighted push-button switch or the P8 BELL CUTOUT switch to stop the bell sound and turnoff the P7 FIRE WARN lights.The P8 wheel well light stays on until the alarm conditions goes off.Push the OVHT/FIRE test switch to start a test of the wheel well fire detection system. <<<<<<< Is this it?????????????115vac power must be on to do a test of the Wheel well fire detection system.These are the Flight compartment indications of a Wheel well fire:-A] P8-1 WHEEL WELL light comes on.B] P7 FIRE WARN light comes on.C] P9 AURAL WARNING UNIT gives a bell sound.To stop the bell sound, push one of these switches:-A] P8 panel BELL CUTOUT push-button.B] P7 panel FIRE WARN light.C] P28 APU GROUND CONTROL panel.If you have a wheel well fire alarm, the MAINT ADV light on the compartment overheat detection control module comes on.

The switch for the fire test is to the left of the #1 Fire Switch.

The switch for the fire test is to the left of the #1 Fire Switch.

Right,There is no "unique switch" to test only the Wheel Well fire system.

The switch for the fire test is to the left of the #1 Fire Switch.

Yes, and it tests all the fire/overheat detection systems, but they are speaking about another "ghost" switch about the wheel well fire detector.And I'm curious to see it as it is something useless.Just to clear some items:P7 is the Glareshield panel (MCP)P8 is the pedestalP9 is near the left foot of the copilot, under the right FMC and it is the aural warning module. It has no switch, except for few configurations wich have an aural warning test switch on it.On P7 there are the 2 FIRE WARN lights/cutout switchesOn P8-1 there is the fire panel, with the handles, test switches (2 switches, one for the fire system, one for the squibs/bottles), bell cutout and various lights.So, I want to see this hidden switch that seems to be present also on a checklist.

... carrying out the electrical power up SP on the ngx, specifically, the WW fire warn system test; it takes 4 presses of the bell cut-out switch to silence the aural alert/extinguish the fire warn switch. Is anyone else experiencing this?

 

Brian Nellis.