I've been starting to the NGX more and more recently and have come into, what might be, a bit of an issue.

I never play with the doors while on the ground at the gate or even use GSX or AES which fiddles with them too but when I taxi out for departure for example, I get the master caution light with 'DOORS' illuminated on the F/O side. I check the overhead and to my disbelief the 'LEFT FWD OVERWING' and the 'RIGHT FWD OVERWING' lights are too illuminated yet on the external view neither doors are open.

I continued to taxi and just as I was lining up on the runway the caution went out and never had the issue for the rest of the flight.

 

Thanks,

Just read the introduction manual or do a search in the forum, you have to read only few pages to find that it is something normal and that happens also on the real plane, if the light turns off after few seconds it is a normal condition.

Quite interesting information, thanks. So, what does it mean if one of these lights is on?

That's what the QRH (Quick Reference Handbook) is for. The Alpha Index will take you to page 1.4, 1.8, 1.13 or 1.14 as appropriate.

 

The QRH tells you what to do for every light that can go off.

Boeing in the next gen. aircraft changed the overwing exit doors, and in the NGs those doors open outward.

To prevent that a passenger could open it when not required, boeing added a locking mechanism that locks the overwing exits from takeoff, when throttles are advanced, to the touchdown.

So when you advance the throttles the locking mechanism will move to lock the exits, but, if there is no sufficient lubrication, or, temperature is low, or the mechanism is pretty dirt or old, it could need few more seconds to lock the door. This will reflect in a master caution and door alert, but, it is perfectly normal if it then disappears. If not, abort take off as the door is not secured.

Boeing in the next gen. aircraft changed the overwing exit doors, and in the NGs those doors open outward.

To prevent that a passenger could open it when not required, boeing added a locking mechanism that locks the overwing exits from takeoff, when throttles are advanced, to the touchdown.

So when you advance the throttles the locking mechanism will move to lock the exits, but, if there is no sufficient lubrication, or, temperature is low, or the mechanism is pretty dirt or old, it could need few more seconds to lock the door. This will reflect in a master caution and door alert, but, it is perfectly normal if it then disappears. If not, abort take off as the door is not secured.

 

interesting, always nice to know exactly what the story behind those oddities actually is.

Boeing in the next gen. aircraft changed the overwing exit doors, and in the NGs those doors open outward.

To prevent that a passenger could open it when not required, boeing added a locking mechanism that locks the overwing exits from takeoff, when throttles are advanced, to the touchdown.

So when you advance the throttles the locking mechanism will move to lock the exits, but, if there is no sufficient lubrication, or, temperature is low, or the mechanism is pretty dirt or old, it could need few more seconds to lock the door. This will reflect in a master caution and door alert, but, it is perfectly normal if it then disappears. If not, abort take off as the door is not secured.

 

Thank you for the explanation :)

Ain't outward opening doors kinda scary as a thought? Wouldn't feel very comfortable sitting next to one of those.

They can be opened in less time than the old version and will not remain in the hostess hands or is not required to launch them on the wings. It is better for an emergency situation.

That makes perfect sence. What I'm not really sure is how they guarantee that at some point one of the doors explodes at high alt due to the pressure differantiation between the cabin and the outside air.

 

I thought that was exactly the reason why they build (or used to build) all doors opening inwards...

 

Don't say that it'll happen, but from the sound of it is surely is another potential danger. Defective material, human error, poor maintenance... We've seen this happening numerous times!

That makes perfect sence. What I'm not really sure is how they guarantee that at some point one of the doors explodes at high alt due to the pressure differantiation between the cabin and the outside air.

 

I thought that was exactly the reason why they build (or used to build) all doors opening inwards...

 

Don't say that it'll happen, but from the sound of it is surely is another potential danger. Defective material, human error, poor maintenance... We've seen this happening numerous times!

 

You worry too much fella.

If I was worried I would stay in my house doing nothing mate!

 

It's just something that came as a thought when I read the post. :Thinking:

 

:p0502:

When you fly an airbus, a 747, an md11, a CRJ, and much more, you have some doors that opens outward.

What guaranties that they will not open are the projects and tests made on them, are the quality checks and controls, maintenance and so on.

In the past on MD11 and 747 a defective cargo locking system caused the door to be opened in flight, bad design of them.

On the 737 this is not yet happened, they are now one of the most used airplanes and no problems about them, I think they are definetly secure ;)

In the past on MD11 and 747 a defective cargo locking system caused the door to be opened in flight, bad design of them.

 

Wasn't that more the DC-10? I'm not trying to pick at you. I just thought it was the DC-10. If you have any MD-11 reports for the cargo door, I'd definitely like to know about them. I'm definitely into studying incident/accident reports.

I may be wrong here, but I thought the design of the DC-10 cargo door and the MD-11 cargo door really wasn't that different?