LMP737 From , joined Dec 1969, posts, RR: Posted (7 years 3 months 3 weeks 5 days 2 hours ago) and read 3098 times:
Starting in 2008 Boeing is going to offer carbon brakes on the 737NG. The brakes will be supplied Goodrich and Messier-Bugatti. Total weight savings is going to be around 700lbs.
As someone who has changed 737NG brakes all I can say is, why didn't they do this when they launched the program? After all, Boeing spent a lot of money updating everything else.
2H4 From United States of America, joined Oct 2004, 8950 posts, RR: 62 Reply 1, posted (7 years 3 months 3 weeks 5 days 2 hours ago) and read 3093 times:
AIRLINERS.NET CREW HEAD DATABASE EDITOR
Quoting LMP737 (Thread starter): why didn't they do this when they launched the program?
Perhaps the brakes weren't ready from a technical or certification standpoint.
MrChips From Canada, joined Mar 2005, 911 posts, RR: 0 Reply 4, posted (7 years 3 months 3 weeks 4 days 23 hours ago) and read 3012 times:
Quoting Jush (Reply 2): Sorry just to inform you it's already being discussed here
Doesn't matter anyways...this is Tech/Ops, where the discussion will take an entirely different course to Civil Aviation. So even though it might be interesting to get the opinions of the unwashed masses in Civ Av, chances are much better that you will get REAL answers here.
MX757 From United States of America, joined Aug 2005, 602 posts, RR: 12 Reply 5, posted (7 years 3 months 3 weeks 4 days 7 hours ago) and read 2915 times:
700 pounds in weight savings and they last twice as long as the current steel brakes. Now that's impressive!
Quoting MrChips (Reply 4): Doesn't matter anyways...this is Tech/Ops, where the discussion will take an entirely different course to Civil Aviation. So even though it might be interesting to get the opinions of the unwashed masses in Civ Av, chances are much better that you will get REAL answers here.
MR.Chips,
Welcome to my RU list. Well said!
I always wonder why the aviation guru "JerkAmerica" never posts in the Tech/OPs forum?
Jush From Germany, joined Apr 2005, 1636 posts, RR: 4 Reply 6, posted (7 years 3 months 3 weeks 4 days 7 hours ago) and read 2912 times:
Quoting MrChips (Reply 4): Doesn't matter anyways...this is Tech/Ops, where the discussion will take an entirely different course to Civil Aviation. So even though it might be interesting to get the opinions of the unwashed masses in Civ Av, chances are much better that you will get REAL answers here.
Alright then, I just thought the first thread wins the race as it already had answers. But then again it's A.net there is no sense here. And moving another thread isn't possible, heh.
Regds
jush
There is one problem with airbus. Though their products are engineering marvels they lack passion, completely.
Rsbj From United States of America, joined Jan 2006, 152 posts, RR: 0 Reply 7, posted (7 years 3 months 3 weeks 4 days 5 hours ago) and read 2890 times:
I'm wondering how 700 pounds can be saved when the brakes don't weigh that much in the first place. I've seen maintenance change them during one of my walk-around's, and two guys easily pulled them off the spindle and place them on a cart. Perhaps there are much more extensive weight savings elsewhere.
Zeke From Hong Kong, joined Dec 2006, 7727 posts, RR: 73 Reply 9, posted (7 years 3 months 3 weeks 4 days 4 hours ago) and read 2883 times:
Quoting LMP737 (Thread starter): why didn't they do this when they launched the program? After all, Boeing spent a lot of money updating everything else.
Dont know, think they have been on the 320 for over a decade. Made by the same people.
Quoting LMP737 (Thread starter): Total weight savings is going to be around 700lbs.
Seems over the top to me, the number seems overstated. 80 kg a wheel is a lot of mass, carbon brakes still require hydraulics and discs to work.
We are addicted to our thoughts. We cannot change anything if we cannot change our thinking – Santosh Kalwar
2H4 From United States of America, joined Oct 2004, 8950 posts, RR: 62 Reply 10, posted (7 years 3 months 3 weeks 4 days 3 hours ago) and read 2874 times:
AIRLINERS.NET CREW HEAD DATABASE EDITOR
Quoting Zeke (Reply 9): 80 kg a wheel is a lot of mass, carbon brakes still require hydraulics and discs to work.
Yeah, but if I'm not mistaken, the discs are the parts being converted to carbon. And aren't these the heaviest components in the brake assemblies?
FutureUALpilot From United States of America, joined May 2000, 2561 posts, RR: 8 Reply 11, posted (7 years 3 months 3 weeks 4 days 3 hours ago) and read 2873 times:
Quoting Rsbj (Reply 7): I'm wondering how 700 pounds can be saved when the brakes don't weigh that much in the first place.
Perhaps the new brakes allow for the removal of components that formerly were needed for the "old" style brakes? Just my .02
LMP737 From , joined Dec 1969, posts, RR: Reply 12, posted (7 years 3 months 3 weeks 4 days 3 hours ago) and read 2873 times:
Quoting Zeke (Reply 9): Dont know, think they have been on the 320 for over a decade. Made by the same people.
I've heard "commonality" with the classic 737 used as a reason. Although I'm not sure how common the brakes on later model classic are compared with NG brakes since I have never worked on classics. Anyway guess what I'm getting at is the Boeing put all that money into changing the 737 they should have just taken that extra step and put carbon brakes on it.
Quoting Zeke (Reply 9): Seems over the top to me, the number seems overstated. 80 kg a wheel is a lot of mass, carbon brakes still require hydraulics and discs to work.
It's actually pretty accurate. I've worked on both the MD-80 and MD-90. The MD-80 uses steel brakes while the MD-90 uses carbon brakes. On the 90 two guys can easily lift the brake by hand onto the gear. On the 80 unless you want your spine to look like a question mark you had better use a cheery picker.
LMP737 From , joined Dec 1969, posts, RR: Reply 13, posted (7 years 3 months 3 weeks 4 days 3 hours ago) and read 2867 times:
Quoting Rsbj (Reply 7): I'm wondering how 700 pounds can be saved when the brakes don't weigh that much in the first place. I've seen maintenance change them during one of my walk-around's, and two guys easily pulled them off the spindle and place them on a cart. Perhaps there are much more extensive weight savings elsewhere.
Thoughts?
It can be done. However if you want to avoid injury using "mechanical aids" is the best route. See my above post for further info.
Okie From United States of America, joined Jul 2003, 2378 posts, RR: 3 Reply 14, posted (7 years 3 months 3 weeks 4 days 1 hour ago) and read 2838 times:
700 lbs is a significant amount of weight to be hauling around day in and day out.
I would suspect the major issue about putting carbon brakes on the 737 has been cost. The price of using carbon brakes has come down as the technology has evolved, add in less fuel in a high fuel cost environment, less Mx, then the technology becomes more attractive.
While not exactly related to aircraft I can tell you that in the last 15 years the cost of using carbon brakes in racing applications has come down more than 50% as the technology has evolved. Parts that cost $3,000 each 15 years ago are now in the $1250 range.
LMP737 From , joined Dec 1969, posts, RR: Reply 15, posted (7 years 3 months 3 weeks 3 days 19 hours ago) and read 2798 times:
Okie:
I would imagine keeping costs down during the R&D of the 737NG was an issue. Which is kind of odd though when you look at the money Boeing spent on the program. Nickles and dimes I guess.
Rolfen From Germany, joined Jan 2006, 1764 posts, RR: 2 Reply 16, posted (7 years 3 months 3 weeks 3 days 18 hours ago) and read 2791 times:
Quoting Rsbj (Reply 7): I'm wondering how 700 pounds can be saved when the brakes don't weigh that much in the first place. I've seen maintenance change them during one of my walk-around's, and two guys easily pulled them off the spindle and place them on a cart. Perhaps there are much more extensive weight savings elsewhere.
Thoughts?
From what I know carbon has a much higer resistance to heat and does not loose it's braking properties at high temperatures. This might mean that fewer brake discs will be needed on the plane, hence the big weight saving.
HAWK21M From India, joined Jan 2001, 31201 posts, RR: 58 Reply 17, posted (7 years 3 months 3 weeks 3 days 14 hours ago) and read 2756 times:
Quoting Rolfen (Reply 16): From what I know carbon has a much higer resistance to heat and does not loose it's braking properties at high temperatures. This might mean that fewer brake discs will be needed on the plane, hence the big weight saving.
LONGisland89 From United States of America, joined Jan 2006, 634 posts, RR: 0 Reply 19, posted (7 years 3 months 1 week 1 day 16 hours ago) and read 2572 times:
Aren't the current brakes on the 737 series made of magnesium or is it some other kind of alloy?
Avioniker From United States of America, joined Dec 2001, 1109 posts, RR: 11 Reply 20, posted (7 years 3 months 1 week 1 day 2 hours ago) and read 2553 times:
Quoting LONGisland89 (Reply 19): Aren't the current brakes on the 737 series made of magnesium or is it some other kind of alloy?
The current brakes are steel.
Magnesium would make for some very impressive pyrotechnics when the plane is approaching the gate.
One other big advantage to using carbon (sepcarb) brakes is that they are more effective as they grow hotter.
The certification costs on the NG weighed against the commonality issues were extremely high. Boeing chose to spread them over a number of years allowing them to use other manufacturers' data in the process. They saved millions doing it that way.
One may educate the ignorance from the unknowing but stupid is forever. Boswell; ca: 1533
Amtrosie From United States of America, joined Jan 2005, 274 posts, RR: 1 Reply 21, posted (7 years 3 months 1 week ago) and read 2501 times:
Quoting LMP737 (Reply 12): I've heard "commonality" with the classic 737 used as a reason. Although I'm not sure how common the brakes on later model classic are compared with NG brakes since I have never worked on classics. Anyway guess what I'm getting at is the Boeing put all that money into changing the 737 they should have just taken that extra step and put carbon brakes on it.
I have worked all the "classics" and I know there are diferent P/N's for the various series.
As to the weight savings, not only are the carbon disks lighter and with less heat build-up, but with the reduced heating of the brake disks the housings can be re-designed. The stress on them is phoenominal. Almost every brake I have sent for overhaul has a housing problem, cracking or other, almost all related to heat retention.
Bravogolf From United States of America, joined Apr 2005, 535 posts, RR: 1 Reply 22, posted (7 years 3 months 6 days 22 hours ago) and read 2487 times:
I was still confused if the disks themselves are carbon. I went to the Goodrich site. They had a picture that looked like carbon disks but no definate explination. I then went to the http://www.messier-bugatti.com site. Moving around this site there is much information on their carbon brakes. Yes the rotors are carbon and the regitered trademark is Sepcarb. ALSO the site has a link to information that the 787 will have electric brakes. Both the rotors and stators will be made of carbon and activated by an electric motor.
Phollingsworth From United Kingdom, joined Mar 2004, 825 posts, RR: 6 Reply 23, posted (7 years 3 months 6 days 18 hours ago) and read 2458 times:
I seem to remember the reason that the 737NGs have steel brakes is because a certain launch customer required them. There are a number of proposed improvements that were not made at the request of this customer. It is kind of amazing what a launch customer can force a manufacturer to do. Take for instance the 777 style flight deck and cabin on the 767-400