Question for 737 NG Drivers

[wooferdog]

To you NG drivers out there:

1. What conditions must be met for the reversers to deploy?

2. What conditions must be met for the spoilers to deploy?

No sarcasm, please.

Thanks.

 

[Zdriver]

1. Radio altimeter <10' altitude or air/ground safety sensor in the ground mode.

2. I'm assuming you mean ground operation...
auto speedbrake:
-lever armed
-speedbrake armed light illuminated
-both thrust levers retarded to idle
-main landing gear spin up <60kts
-right main strut compressed opening the mechanical linkage to the ground
spoiler shutoff valve
-radio altitude <10'

 

[GuppyWN]

I've seen where the above were met and the T/R's did not deploy. I'll wait until the NTSB does a prelim.

Without mitigating factors I'd be pretty hard to use an entire 8900 foot runway with enough residual energy to break apart the airplane.

Gup

 

[Green Banana]

1. Radio altimeter <10' altitude or air/ground safety sensor in the ground mode.

2. I'm assuming you mean ground operation...
auto speedbrake:
-lever armed
-speedbrake armed light illuminated
-both thrust levers retarded to idle
-main landing gear spin up <60kts
-right main strut compressed opening the mechanical linkage to the ground
spoiler shutoff valve
-radio altitude <10'

Actually, not true. The speedbrake will deploy automaticly when you deploy the thrust reverse.

 

[Homer Jay]

actually, not true. The speedbrake will deploy automaticly when you deploy the thrust reverse.

what?!?!

 

[Green Banana]

what?!?!

What?!?! , What?!?!
If you forget to arm the speed brake, Boeing designed it to auto deploy. It is the same system that deploys them on a rejected takeoff without the lever in the ARM position.

 

[Homer Jay]

What?!?! , What?!?!
If you forget to arm the speed brake, Boeing designed it to auto deploy. It is the same system that deploys them on a rejected takeoff without the lever in the ARM position.

I don't recall ever reading that. What's the point of arming them then if they'll auto-deploy anyway? I'm trying to find it in my manual. If it's true, just goes to show you learn something new everyday!

 

[ImbracableCrunk]

Speed Brake Lever DOWN During Landing or RTO
If the SPEED BRAKE lever is in the DOWN position during landing or rejected
takeoff, the Automatic Speed Brake System operates when these conditions
occur:
- main landing gear wheels spin up (more than 60 kts)
- both thrust levers are retarded to IDLE, and
- reverse thrust levers are positioned for reverse thrust
The SPEED BRAKE lever automatically moves to the UP position and spoilers
deploy.

I guess we arm the SB just in case there's a problem with the T/Rs. They'll deploy sooner if you arm them, too, I suppose.

 

[CMRJetDriver]

Apparently the Space Shuttle only needs around 9000' as well. Granted they don't land it in the rain and some distances were longer.


STS-1

April 14, 1981, 10:20:57 a.m. PST, Runway 23, Edwards Air Force Base, Calif. Rollout distance: 8,993 feet. Rollout time: 60 seconds. Landing Weight: 194,184 lbs.

STS-2

November 14, 1981, 1:23:11 p.m. PST, Runway 23, Edwards Air Force Base, Calif. Rollout distance: 7,711 feet. Rollout time: 50 seconds. Landing Weight: 204,262 lbs.

etc, etc...

 

[flyboyike]

I don't recall ever reading that. What's the point of arming them then if they'll auto-deploy anyway?

Well, I can see it being beneficial if either or both reversers don't deploy.