Sign in to follow this  
Turlad

Alternate gear extension

Recommended Posts

Just wondering if anyone knowledgeable can answer a quickie...

 

Using the alternate gear extension system, is there an order to which you do first - wing gear or nose/body gear?

 

I've had a problem wear selecting nose/body gear alternate first is fine and they drop, but then selecting wing gear afterwards doesn't do anything (After doing the Gear disagree QRH, I landed without the wing gear - wasn't as bad as I thought....)

 

In the reverse, select wing gear and then nose/body it all works fine, everything extends. It's repeatable in two flights so far.....I've had a good look at FCOM 2 and the QRH procedure but it doesn't specify. 

 

Adam Turley

Share this post


Link to post
Share on other sites
Help AVSIM continue to serve you!
Please donate today!

 

 


sing the alternate gear extension system, is there an order to which you do first - wing gear or nose/body gear?

 

Nope. At least the QRH doesn't specify.

 

QRH page 13.10 (350 of the PDF).

Share this post


Link to post
Share on other sites

Sorry to drag this up again, but it's still bugging me. I think it's a bug to be honest. There might be a deeper systems knowledge answer here as well though....

 

The wing gear alternate extension will not work if you do it after the nose/body alternate extension. Other way round is fine. The QRH's make no mention of order so I assume it's unimportant. At first I thought it might be related to gear door interference issues, but after studying the extension process I don't think that's it. 

 

In a separate issue - I was able to get a LAND 3 announciation in a Two-Engine landing situation. The auto-throttle was therefore off / disconnected - Everything in my RW experience tells me we need autothrottle for autoland, could be wrong though.... FCOM 2 isn't absolutely clear on LAND 3 requirements....

 

Adam Turley

Share this post


Link to post
Share on other sites

No system schematic or aircraft manual shows a dependency of LAND2/3 on AT. I do not think any Boeing airplane does to be honest not just this one.

Share this post


Link to post
Share on other sites

Adam,

 

Nose/Body and Wing Alternate extension are totally independent of one another.

 

I haven't seen this behavior you report but i've added to the system to take a look at.

 

The alternate modes are largely cosmetic, since Microsoft thought all aircraft are basically C-172s...  but you should be able to throw them out in whatever fashion you like.

Share this post


Link to post
Share on other sites
The QRH's make no mention of order so I assume it's unimportant.

 

 

I don't think Boeing expects you to lose two entire hydraulic systems at once (since hydraulic fuses were installed after the big Japan Air Lines crash "JAL 123")

 

If the nosewheel causes any air buffeting on the main gear, I wonder if it would assist the extension of the main gear? Gravity is usually enough, but I can see how airloads on the body gear would assist extension/locking. I'm not sure of the geometry of the wing gear.

 

Cheers

John H Watson

Share this post


Link to post
Share on other sites

Adam,

 

I was able to find the issue and correct it.  With the pending update you'll be able to throw them out however you like. 

Share this post


Link to post
Share on other sites

Adam,

 

I was able to find the issue and correct it.  With the pending update you'll be able to throw them out however you like. 

 

Great, thanks Robert for taking a look, appreciated. 

 

Can't say how much we all appreciate a fully featured product at release, with a very very small number of relatively minor issues.... It's something of a rarity these days.

 

Adam Turley

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Sign in to follow this