The completely cold and dark startup is getting a lot of attention...but, how often do pilots start from a C&D situation in real life? An aircraft isn't C&D after it has just been 'turned around' is it? For how long can they be kept 'warm', stringing flights together, with different crews perhaps, etc.What's common practice in this regard? Best,Martijn

You are right for that there is no need to start from a cold and dark cockpit during turn around, unless there is a crew change. This is happeninig between 0 and maybe 4 times a day for one crew. When you come on the plane in the morning you have to do all tests and switching as in the Operating Manual. Prior the next flight without crew change, there are only certain things left to do. Much less than during cold and dark start-up. If there is a crew change and you can directly transfer the plane to the next crew there is also no need to do all the switching again.So all depends on the fact if the airplane stands alone and uncompanied on the apron and is waiting for the next crew.I hope I could explain a little bit of the workflow out here.GreetingsSebastian

"The completely cold and dark startup is getting a lot of attention... but, how often do pilots start from a C&D situation in real life?"Don't forget there are a lot of real life maintenance engineers on this forum, Martijn ;-) We might be faced with C&D cockpits every day. We have to wake them up in the morning and put them to bed at night (especially at airports with curfews ;-)).Like pilots, the more we use simulators, the more confident we become in our jobs. Only a few weeks before buying the sim, I was very hesitant when someone told me to go power up a 737.Also, starting from a dead ship teaches everyone about aircraft electrical systems, hydraulic systems, airconditioning systems, etc...Cheers.Ian.

Hi Ian,I certainly didn't mean to imply that the attention to C&D was unwarrented-in fact I think it's interesting too and it certainly should be part of the simulation. I was simply wondering about what 'a day in the life' of an airliner was like and whether they are being powered down after each and every flight or not-or whether they can remain in continuous use for maybe even more than one day or so.Best,Martijn

Ian,I have a question for you: Do the pilots who first get to a plane in the morning start the plane up from C&D, or do the maintenence staff start it up from C&D and then hand it over to the pilots?

"I have a question for you: Do the pilots who first get to a plane in the morning start the plane up from C&D, or do the maintenence staff start it up from C&D and then hand it over to the pilots?"I can't really vouch for other airports, but it is very unlikely that a big Boeing flight crew would be required to start up an aircraft from C&D in any part of the world. I'm sure if they didn't practise this in their sims, they would probably forget how to do it ;-)The pilots are often the last of the crew to turn up at the start of the day, so it's up to the engineers to get things up and running. There may be circuit breakers to reset (some are pulled on long transits for safety and system longevity), pitot/static probe covers to remove (to stop water, bugs, etc getting in them), fuel to be loaded and airconditioning systems to be started up. Often on a large aircraft, it takes some time to get the cabin up/down to a habitable temperature. The galley food refrigerators (or rather, "chillers") don't always function very well if the cabin is hot, so the food, which may be loaded onto the aircraft over an hour before departure, may go "off" before it is served. In many cases, aircraft with EICAS systems will generate a number of fault messages/flags on power up. There are literally dozens of computers to be booted up, and as you know, computers don't like to be switched off and on ;-) The built-in fault detecting circuits in aircraft computers generate these fault messages. We try to make sure that all the bugs have been ironed out before the crew get there. There may even be simple checks to do on the flight deck or in the cabin, to make sure the flight runs smoothly. In some cases, the crew may arrive at an aircraft 20~25 minutes before a long international flight, so there would be no way they could go from C&D to pushback in such a short time. We are often on an the aircraft an hour or two before departure. The concientious engineer may even start an IRS alignment to help things along (although in most cases, the pilots prefer to do it themselves.... They may let us fix the IRS's, but things like this start to bite into their preflight responsibilities). ;-)BTW, some airlines run their 737's 24 hours a day, so may not see "C&D" for some time. Here in Sydney, we usually put them to bed for the night, to stop the neighbours grumbling ;-) However, they may do several flights a day without being shut down (electrical-wise).Anyway, I'm rambling again.....Cheers.Ian.

It looks like it is different from airline to airline.Here, where I work for, we power up the aircraft on our own. No engineers helping us for the basic tests. They can be called, if any problem occurs. What they definetly do is, preparing the aircraft from their side. As already said, checking for pitot covers, gear pins, CBs, water supply in winter etc. But swithcing on the aircraft is all done by the flight crew. Sometimes the battery is switched on and Ground Power is connected. When you get used to it, there is no problem waking up the aircraft in a very short time. Summary:First flight of the day: Maintenance is providing the aircraft after their night checks normally cold and dark. Switching and all test by flight crew.Transit time without crew change: Only a some switching is taking place (switching on Seat belt signs, Nav set up, Autobrake, Cruise Alt at Cabin Panel, AP Setup etc.)Transit time with crew change (no personal transfer to next crew): The leaving crew switches everything off and leaves the plane. The new crew will start up everything again. But only certain tests have to be performed (e.g. no STBY Power test as in morning, no takeoff warning test, but on the other hand a fire warning test will be performed again).But as I said in the beginning - this all might be different from operator to operator.GreetingsSebastian

Hi Ian,Hope all is well "down there"!!!!As usual your "rambling" is very instructive. I often wondered about the "cold and dark" startups myself. Thanks for your participation in this forum. A major benefit to all of us who look here everyday!!

Thanks, Ian, Sebastian,very intersting this.That is one of the things I was wondering about-how long can these aircaft keep going? I imagine some (especially the longer range types) may 'outrun' the day/night horizon for some time, perhaps even on a number of consecutive flights if they aren't being shuttled back and forth-but I suspect that in itself would be rare.Thanks, Martijn

Thanks for the insight, Seb :-)I keep forgetting how compact the 737 is... It takes me 10 minutes just to walk around a 747 :-lolDuring your preflight checks, do you just do a basic perimeter walkaround.. or do you check inside the wheel wells? I'm simply amazed at how much they cram into those things (apart from the wheels, that is).http://members.ozemail.com.au/~b744er/737/...ghtHandSide.jpgI have no idea what it all does!Cheers.Ian.

Well Ian,Aren't these the pulleys for the elevator controls? ;-)http://forums.avsim.net/user_files/37279.jpgThe food elevator I mean...Regards,

"The food elevator I mean..."LOL.... And I thought they were for bringing the washing line in??? :-)And aren't those tanks, hot water boilers for the captain's coffee?Cheeers.Ian.

Ian,>And aren't those tanks, hot water boilers for the captain's coffee?Actually I think most of the piping seen in the wheel well is there to produce the captain's coffee! :-DRegards,