Sponsor Message:
Aviation Technical / Operations Forum
My Starred Topics | Profile | New Topic | Forum Index | Help | Search 
How Do You Control The Ground Spoilers?  
User currently offlineBio15 From Colombia, joined Mar 2001, 1089 posts, RR: 7
Posted (12 years 2 months 1 week 6 days 12 hours ago) and read 4475 times:

Hi everyone. I would just like to know if there is a different stick used to activate the ground spoilers, or if the same speed brake handle is used. If they are the same, what determines when to deploy ground spoilers and when the speed brakes (or both at a time)?

I have known that quick descents are not uncommon, and that high descent rates can be achieved by the aircraft. I wanted to know if there are any limitations due to pressurization issues as to the descent speed. I once went into a 767 flight deck and noticed the VS pointing to the -4500 fpm, which I thought was rather high. Is it really?

Thanks in advance everyone.

-Alfredo

7 replies: All unread, jump to last
 
User currently offlineSeiple From , joined Dec 1969, posts, RR:
Reply 1, posted (12 years 2 months 1 week 6 days 12 hours ago) and read 4460 times:

Regarding spoilers....

In flight, the flight spoilers are activated by the speed brake handle. I know that Boeings have a spoiler mixer that activates them in proportion to the ailerons for better roll control.
Ground spoilers will only activate on the ground. They require weight on wheels via a squat switch or something similar. When arming the spoilers, normally one set (flight or ground) will deploy with the squat switch activation while the other set requires some sort of power input (such as reverse thrust).


User currently offlineAvioniker From United States of America, joined Dec 2001, 1109 posts, RR: 11
Reply 2, posted (12 years 2 months 1 week 6 days 12 hours ago) and read 4446 times:


View Large View Medium
Click here for bigger photo!

Photo © Aric Thalman
View Large View Medium
Click here for bigger photo!

Photo © Chris Coduto


The ground spoilers are normally actuated using the spoiler handle. The handle is most normally located to the immediate left of the throttle levers. They may also be deployed on landing automatically through an electrical actuator connected to the control quadrant under the floor. On many aircraft there is an interlock so that the ground spoilers do not operate in flight or when the aircraft weight is not on the landing gear. The flight spoilers normally work through a mixing or proportioning mechanism to compliment the ailerons thus requiring less aileron deflection to achieve a higher roll rate. They deploy with the ground spoilers when the spoiler handle is pulled.



One may educate the ignorance from the unknowing but stupid is forever. Boswell; ca: 1533
User currently offlineAAR90 From United States of America, joined Jan 2000, 3494 posts, RR: 46
Reply 3, posted (12 years 2 months 1 week 6 days 8 hours ago) and read 4389 times:

Depends upon the aircraft. Most utilize a single "speedbrake" or "spoiler" handle. Some of those have a "flight" limit position and some do not. Those that do "normally" utilize some form of physical restriction to prohibit movement beyond the flight limit when no weight on wheels is sensed. Notice the use of "some" and "normally." Naturally there are exceptions. i.e. F-100 uses "Lift Dumpers" which are "armed" by the pilots and activate with weight on wheels sensing.



*NO CARRIER* -- A Naval Aviator's worst nightmare!
User currently offlineBio15 From Colombia, joined Mar 2001, 1089 posts, RR: 7
Reply 4, posted (12 years 2 months 1 week 3 days 6 hours ago) and read 4282 times:

Thanks for answering my question everyone

-Alfredo


User currently offlineRick767 From United Kingdom, joined Jan 2000, 2662 posts, RR: 51
Reply 5, posted (12 years 2 months 1 week 3 days 6 hours ago) and read 4276 times:

As AAR90 said, every aircraft is different and there will always be exceptions.

On the 767-300 for example, all six spoiler panels on each wing activate as both ground spoilers and roll control spoilers / speedbrakes..

On the 757, however, only the three outboard and two inboard spoilers act in this way, with all six operating on the ground.

In the latter case, the distiction between air and ground operation is achieved via the "air / ground logic system"



I used to love the smell of Jet-A in the morning...
User currently offlineBio15 From Colombia, joined Mar 2001, 1089 posts, RR: 7
Reply 6, posted (12 years 2 months 1 week 3 days 5 hours ago) and read 4262 times:

Hi Rick767, thanks for responding. Since you fly the 767, do you know if there are any limits regarding descent rates? What would be considered a 'high' descent rate on the 767?
Thanks in advance

-Alfredo


User currently offlineCdfmxtech From United States of America, joined Jul 2000, 1341 posts, RR: 26
Reply 7, posted (12 years 2 months 1 week 3 days 1 hour ago) and read 4236 times:

What would be considered a 'high' descent rate on the 767?

one where the flight attendants are pinned to the ceiling!!


Top Of Page
Forum Index

Reply To This Topic How Do You Control The Ground Spoilers?
Username:
No username? Sign up now!
Password: 


Forgot Password? Be reminded.
Remember me on this computer (uses cookies)
  • Tech/Ops related posts only!
  • Not Tech/Ops related? Use the other forums
  • No adverts of any kind. This includes web pages.
  • No hostile language or criticizing of others.
  • Do not post copyright protected material.
  • Use relevant and describing topics.
  • Check if your post already been discussed.
  • Check your spelling!
  • DETAILED RULES
Add Images Add SmiliesPosting Help

Please check your spelling (press "Check Spelling" above)


Similar topics:More similar topics...
How Do You Store The Frequncy? posted Sun Oct 30 2005 13:02:55 by Diego
How Do You Steer Down The ILS? posted Wed May 14 2003 05:51:25 by Flyordie
How Do You Track Flight Hours posted Fri Nov 3 2006 19:09:33 by Airfoilsguy
How Do You Start A Commercial Plane? posted Sun Oct 8 2006 21:07:06 by Deaphen
How Do You Start 737 Engine? posted Sun Nov 20 2005 02:35:24 by BR715-A1-30
How Do You Start An Airliner? posted Sun Jul 24 2005 19:49:18 by RobK
How Do You Change A Wheel On An Airliner? posted Sat May 7 2005 15:47:53 by Ajet
How Do You Get Support posted Thu Feb 24 2005 14:47:46 by Alberchico
How Do You "plug" Doors? posted Tue Oct 5 2004 19:04:17 by AT
Descent:do You Plan To Use Spoilers? posted Thu Aug 26 2004 09:30:30 by XXXX10

Sponsor Message:
Printer friendly format