Ttdfjt

How do I run a game when my PCs have different approaches to combat?

What does Kasparov mean by "I was behind in three and even in one after six games"?

Why is a dedicated QA team member necessary?

Which Roman general was killed by his own soldiers for not letting them to loot a newly conquered city?

How can I prevent corporations from growing their own workforce?

How do professional electronic musicians/sound engineers combat listening fatigue?

This message is flooding my syslog, how to find where it comes from?

Iterate over non-const variables in C++

How to judge a Ph.D. applicant that arrives "out of thin air"

How can I tell if there was a power cut while I was out?

USA: Can a witness take the 5th to avoid perjury?

Grid/table with lots of buttons

401(k) investment after being fired. Do I own it?

Can I go to the UK from the Schengen on train?

Other than a swing wing, what types of variable geometry have flown?

Why did Saturn V not head straight to the moon?

How can I receive packages while in France?

How to write a sincerely religious protagonist without preaching or affirming or judging their worldview?

Is there a reason why I should not use the HaveIBeenPwned API to warn users about exposed passwords?

How can I make sure my players' decisions have consequences?

Spoken encryption

Q: What is a Checkmate Word™?

Where to place an artificial gland in the human body?

Tikz - Coordinates error when using draw with axis

What powers the air required for pneumatic brakes in aircraft?

For large jets, what is the primary means of slowing down after landing?Do landing planes brake with wheel-brakes or air-brakes or both?What are the relative braking contributions from wheel brakes, spoilers and thrust reversers?What effect would there be if the brakes were locked at touchdown?What is the temperature of the brakes after a typical landing?Have Eddy current brakes ever been used/tested on an aircraft?Do parking brakes lock the wheels and airframe together?How much force are large aircraft brakes able to exert?What is the 'fuel cost' of a pneumatic braking system vs. a hydraulic one, in terms of weight?Do any aircraft have liquid-cooled brakes?

.everyoneloves__top-leaderboard:empty,.everyoneloves__mid-leaderboard:empty,.everyoneloves__bot-mid-leaderboard:empty margin-bottom:0;

8

$begingroup$

What powers the air required for pneumatic brakes in large airliner aircraft? Is it bled from the engines, or do they have a separate motor and pump?

braking

share|improve this question

edited Jul 16 at 8:22

Federico♦

26.8k1616 gold badges110110 silver badges157157 bronze badges

asked Jul 16 at 8:16

securitydude5securitydude5

3,79544 gold badges3030 silver badges6666 bronze badges

$endgroup$

add a comment | 

8

$begingroup$

What powers the air required for pneumatic brakes in large airliner aircraft? Is it bled from the engines, or do they have a separate motor and pump?

braking

share|improve this question

edited Jul 16 at 8:22

Federico♦

26.8k1616 gold badges110110 silver badges157157 bronze badges

asked Jul 16 at 8:16

securitydude5securitydude5

3,79544 gold badges3030 silver badges6666 bronze badges

$endgroup$

add a comment | 

$begingroup$

What powers the air required for pneumatic brakes in large airliner aircraft? Is it bled from the engines, or do they have a separate motor and pump?

braking

share|improve this question

edited Jul 16 at 8:22

Federico♦

26.8k1616 gold badges110110 silver badges157157 bronze badges

asked Jul 16 at 8:16

securitydude5securitydude5

3,79544 gold badges3030 silver badges6666 bronze badges

$endgroup$

share|improve this question

edited Jul 16 at 8:22

Federico♦

26.8k1616 gold badges110110 silver badges157157 bronze badges

asked Jul 16 at 8:16

securitydude5securitydude5

3,79544 gold badges3030 silver badges6666 bronze badges

share|improve this question

edited Jul 16 at 8:22

Federico♦

26.8k1616 gold badges110110 silver badges157157 bronze badges

asked Jul 16 at 8:16

securitydude5securitydude5

3,79544 gold badges3030 silver badges6666 bronze badges

edited Jul 16 at 8:22

Federico♦

26.8k1616 gold badges110110 silver badges157157 bronze badges

edited Jul 16 at 8:22

Federico♦

26.8k1616 gold badges110110 silver badges157157 bronze badges

asked Jul 16 at 8:16

securitydude5securitydude5

3,79544 gold badges3030 silver badges6666 bronze badges

asked Jul 16 at 8:16

securitydude5securitydude5

3,79544 gold badges3030 silver badges6666 bronze badges

2 Answers
2

active

oldest

votes

13

$begingroup$

For a medium size turboprop, the F-27: two separate compressors, driven by the turboprop engines.

From this article

Fairchild’s F-27 is the first American-made plane to use a complete pneumatic system to operate landing gear, wheel brakes, nose wheel steering, propeller brakes, and passenger door operation. It also has an emergency air supply that will lower the landing gears and operate the brakes.

Compressed air for the system is supplied by two 2-cfm, 3300-psi compressors located in each of the engine nacelles. The compressors are driven through a gearbox by Rolls Royce Dart engines, which power the aircraft. They carry their own individual dehydration and filtration equipment to supply clean, dry air at a pressure of 3300 psi

Most present day airliners use the hydraulic system for the landing gear, including wheel braking. For instance on the B737:

The normal brake system and autobrakes are powered by hydraulic system B. If brake pressure drops below 1500psi, hydraulic system A automatically provides alternate brakes which are manual only (ie no autobrake) and the brake pressure returns to 3000psi.

The hydraulic systems are each powered by an Engine Driven Pump and an Electric Motor Driven Pump.

share|improve this answer

answered Jul 16 at 8:57

KoyovisKoyovis

33.2k88 gold badges8888 silver badges175175 bronze badges

$endgroup$

• 
  
  
  

  
  

  
  
  
  
  
  

  
  $begingroup$
  This makes me wonder if the F-27 sounds like a semi-truck when it's taxiing. :)
  $endgroup$
  – Juan Jimenez
  Jul 16 at 10:40
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  $begingroup$
  Yes it would hiss if you were close to the brakes while they were being used but without that squeak noise from those big bellows units. This was something more popular with Russian designs, and I think the Fokker was the only western transport a/c to do that. Lots of technical advantages, but the difficultly of sealing HP air, and controlling humidity, in a system where you are using it to do hard physical work is a nightmare from a reliability standpoint. Once the fire risk for hydraulics was mitigated by the switch to phosphate ester fluid, pneumatic actuation became much less attractive.
  $endgroup$
  – John K
  Jul 16 at 12:53
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  $begingroup$
  Well, yes, the Russians have been manufacturing the very reliable Vedeneyev M14P radial engine for a very long time, and to my knowledge pretty much all of them are air-start. Makes perfect sense. Not a good idea to rely on a battery in the middle of Siberia. :)
  $endgroup$
  – Juan Jimenez
  Jul 16 at 13:07
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  $begingroup$
  As long as you religiously monitor for air leaks and chase them down. The cylinder will hold its charge for months... until a tiny leak starts and then you're screwed, and it's the old hand bombing start method. Years ago I was planning to get checked out in an air-start Wilga to tow gliders until I found out I was going to have to pay for the airplane time myself. The Wilga's AI-14 engine's starter has a battery operated compressor to keep it charged, so you were still dependent on a battery in the end. For reliable starting any time anywhere, hard to beat a hand cranked inertia starter.
  $endgroup$
  – John K
  Jul 16 at 16:47
  

  
  
  
  

add a comment | 

6

$begingroup$

As far as I know, no modern airliner uses air to power the brakes. The systems are hydraulic.

share|improve this answer

edited Jul 16 at 9:29

answered Jul 16 at 8:20

Juan JimenezJuan Jimenez

8,31411 gold badge1212 silver badges5353 bronze badges

$endgroup$

• 
  
  
  

  
  

  
  
  
  
  
  

  
  $begingroup$
  This makes me wonder if OP heard the term "Air Brake" and assumed it meant pneumatic brakes?
  $endgroup$
  – Ron Jensen
  Jul 17 at 15:16
  

  
  
  
  

add a comment | 

Your Answer

StackExchange.ready(function()
var channelOptions =
tags: "".split(" "),
id: "528"
;
initTagRenderer("".split(" "), "".split(" "), channelOptions);

StackExchange.using("externalEditor", function()
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled)
StackExchange.using("snippets", function()
createEditor();
);

else
createEditor();

);

function createEditor()
StackExchange.prepareEditor(
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: false,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: null,
bindNavPrevention: true,
postfix: "",
imageUploader:
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
,
noCode: true, onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
);



);

draft saved

draft discarded

Sign up or log in

StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);

Sign up using Google

Sign up using Facebook

Sign up using Email and Password

Post as a guest

Name

Email

Required, but never shown

StackExchange.ready(
function ()
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2faviation.stackexchange.com%2fquestions%2f66623%2fwhat-powers-the-air-required-for-pneumatic-brakes-in-aircraft%23new-answer', 'question_page');

);

Post as a guest

Name

Email

Required, but never shown

13

$begingroup$

For a medium size turboprop, the F-27: two separate compressors, driven by the turboprop engines.

From this article

Fairchild’s F-27 is the first American-made plane to use a complete pneumatic system to operate landing gear, wheel brakes, nose wheel steering, propeller brakes, and passenger door operation. It also has an emergency air supply that will lower the landing gears and operate the brakes.

Compressed air for the system is supplied by two 2-cfm, 3300-psi compressors located in each of the engine nacelles. The compressors are driven through a gearbox by Rolls Royce Dart engines, which power the aircraft. They carry their own individual dehydration and filtration equipment to supply clean, dry air at a pressure of 3300 psi

Most present day airliners use the hydraulic system for the landing gear, including wheel braking. For instance on the B737:

The normal brake system and autobrakes are powered by hydraulic system B. If brake pressure drops below 1500psi, hydraulic system A automatically provides alternate brakes which are manual only (ie no autobrake) and the brake pressure returns to 3000psi.

The hydraulic systems are each powered by an Engine Driven Pump and an Electric Motor Driven Pump.

share|improve this answer

answered Jul 16 at 8:57

KoyovisKoyovis

33.2k88 gold badges8888 silver badges175175 bronze badges

$endgroup$

• 
  
  
  

  
  

  
  
  
  
  
  

  
  $begingroup$
  This makes me wonder if the F-27 sounds like a semi-truck when it's taxiing. :)
  $endgroup$
  – Juan Jimenez
  Jul 16 at 10:40
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  $begingroup$
  Yes it would hiss if you were close to the brakes while they were being used but without that squeak noise from those big bellows units. This was something more popular with Russian designs, and I think the Fokker was the only western transport a/c to do that. Lots of technical advantages, but the difficultly of sealing HP air, and controlling humidity, in a system where you are using it to do hard physical work is a nightmare from a reliability standpoint. Once the fire risk for hydraulics was mitigated by the switch to phosphate ester fluid, pneumatic actuation became much less attractive.
  $endgroup$
  – John K
  Jul 16 at 12:53
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  $begingroup$
  Well, yes, the Russians have been manufacturing the very reliable Vedeneyev M14P radial engine for a very long time, and to my knowledge pretty much all of them are air-start. Makes perfect sense. Not a good idea to rely on a battery in the middle of Siberia. :)
  $endgroup$
  – Juan Jimenez
  Jul 16 at 13:07
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  $begingroup$
  As long as you religiously monitor for air leaks and chase them down. The cylinder will hold its charge for months... until a tiny leak starts and then you're screwed, and it's the old hand bombing start method. Years ago I was planning to get checked out in an air-start Wilga to tow gliders until I found out I was going to have to pay for the airplane time myself. The Wilga's AI-14 engine's starter has a battery operated compressor to keep it charged, so you were still dependent on a battery in the end. For reliable starting any time anywhere, hard to beat a hand cranked inertia starter.
  $endgroup$
  – John K
  Jul 16 at 16:47
  

  
  
  
  

add a comment | 

13

$begingroup$

For a medium size turboprop, the F-27: two separate compressors, driven by the turboprop engines.

From this article

Fairchild’s F-27 is the first American-made plane to use a complete pneumatic system to operate landing gear, wheel brakes, nose wheel steering, propeller brakes, and passenger door operation. It also has an emergency air supply that will lower the landing gears and operate the brakes.

Compressed air for the system is supplied by two 2-cfm, 3300-psi compressors located in each of the engine nacelles. The compressors are driven through a gearbox by Rolls Royce Dart engines, which power the aircraft. They carry their own individual dehydration and filtration equipment to supply clean, dry air at a pressure of 3300 psi

Most present day airliners use the hydraulic system for the landing gear, including wheel braking. For instance on the B737:

The normal brake system and autobrakes are powered by hydraulic system B. If brake pressure drops below 1500psi, hydraulic system A automatically provides alternate brakes which are manual only (ie no autobrake) and the brake pressure returns to 3000psi.

The hydraulic systems are each powered by an Engine Driven Pump and an Electric Motor Driven Pump.

share|improve this answer

answered Jul 16 at 8:57

KoyovisKoyovis

33.2k88 gold badges8888 silver badges175175 bronze badges

$endgroup$

• 
  
  
  

  
  

  
  
  
  
  
  

  
  $begingroup$
  This makes me wonder if the F-27 sounds like a semi-truck when it's taxiing. :)
  $endgroup$
  – Juan Jimenez
  Jul 16 at 10:40
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  $begingroup$
  Yes it would hiss if you were close to the brakes while they were being used but without that squeak noise from those big bellows units. This was something more popular with Russian designs, and I think the Fokker was the only western transport a/c to do that. Lots of technical advantages, but the difficultly of sealing HP air, and controlling humidity, in a system where you are using it to do hard physical work is a nightmare from a reliability standpoint. Once the fire risk for hydraulics was mitigated by the switch to phosphate ester fluid, pneumatic actuation became much less attractive.
  $endgroup$
  – John K
  Jul 16 at 12:53
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  $begingroup$
  Well, yes, the Russians have been manufacturing the very reliable Vedeneyev M14P radial engine for a very long time, and to my knowledge pretty much all of them are air-start. Makes perfect sense. Not a good idea to rely on a battery in the middle of Siberia. :)
  $endgroup$
  – Juan Jimenez
  Jul 16 at 13:07
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  $begingroup$
  As long as you religiously monitor for air leaks and chase them down. The cylinder will hold its charge for months... until a tiny leak starts and then you're screwed, and it's the old hand bombing start method. Years ago I was planning to get checked out in an air-start Wilga to tow gliders until I found out I was going to have to pay for the airplane time myself. The Wilga's AI-14 engine's starter has a battery operated compressor to keep it charged, so you were still dependent on a battery in the end. For reliable starting any time anywhere, hard to beat a hand cranked inertia starter.
  $endgroup$
  – John K
  Jul 16 at 16:47
  

  
  
  
  

add a comment | 

$begingroup$

For a medium size turboprop, the F-27: two separate compressors, driven by the turboprop engines.

From this article

Fairchild’s F-27 is the first American-made plane to use a complete pneumatic system to operate landing gear, wheel brakes, nose wheel steering, propeller brakes, and passenger door operation. It also has an emergency air supply that will lower the landing gears and operate the brakes.

Compressed air for the system is supplied by two 2-cfm, 3300-psi compressors located in each of the engine nacelles. The compressors are driven through a gearbox by Rolls Royce Dart engines, which power the aircraft. They carry their own individual dehydration and filtration equipment to supply clean, dry air at a pressure of 3300 psi

Most present day airliners use the hydraulic system for the landing gear, including wheel braking. For instance on the B737:

The normal brake system and autobrakes are powered by hydraulic system B. If brake pressure drops below 1500psi, hydraulic system A automatically provides alternate brakes which are manual only (ie no autobrake) and the brake pressure returns to 3000psi.

The hydraulic systems are each powered by an Engine Driven Pump and an Electric Motor Driven Pump.

share|improve this answer

answered Jul 16 at 8:57

KoyovisKoyovis

33.2k88 gold badges8888 silver badges175175 bronze badges

$endgroup$

share|improve this answer

answered Jul 16 at 8:57

KoyovisKoyovis

33.2k88 gold badges8888 silver badges175175 bronze badges

answered Jul 16 at 8:57

KoyovisKoyovis

33.2k88 gold badges8888 silver badges175175 bronze badges

answered Jul 16 at 8:57

KoyovisKoyovis

33.2k88 gold badges8888 silver badges175175 bronze badges

6

$begingroup$

As far as I know, no modern airliner uses air to power the brakes. The systems are hydraulic.

share|improve this answer

edited Jul 16 at 9:29

answered Jul 16 at 8:20

Juan JimenezJuan Jimenez

8,31411 gold badge1212 silver badges5353 bronze badges

$endgroup$

• 
  
  
  

  
  

  
  
  
  
  
  

  
  $begingroup$
  This makes me wonder if OP heard the term "Air Brake" and assumed it meant pneumatic brakes?
  $endgroup$
  – Ron Jensen
  Jul 17 at 15:16
  

  
  
  
  

add a comment | 

6

$begingroup$

As far as I know, no modern airliner uses air to power the brakes. The systems are hydraulic.

share|improve this answer

edited Jul 16 at 9:29

answered Jul 16 at 8:20

Juan JimenezJuan Jimenez

8,31411 gold badge1212 silver badges5353 bronze badges

$endgroup$

• 
  
  
  

  
  

  
  
  
  
  
  

  
  $begingroup$
  This makes me wonder if OP heard the term "Air Brake" and assumed it meant pneumatic brakes?
  $endgroup$
  – Ron Jensen
  Jul 17 at 15:16
  

  
  
  
  

add a comment | 

$begingroup$

As far as I know, no modern airliner uses air to power the brakes. The systems are hydraulic.

share|improve this answer

edited Jul 16 at 9:29

answered Jul 16 at 8:20

Juan JimenezJuan Jimenez

8,31411 gold badge1212 silver badges5353 bronze badges

$endgroup$

share|improve this answer

edited Jul 16 at 9:29

answered Jul 16 at 8:20

Juan JimenezJuan Jimenez

8,31411 gold badge1212 silver badges5353 bronze badges

answered Jul 16 at 8:20

Juan JimenezJuan Jimenez

8,31411 gold badge1212 silver badges5353 bronze badges

answered Jul 16 at 8:20

Juan JimenezJuan Jimenez

8,31411 gold badge1212 silver badges5353 bronze badges