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kitplane01
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Nose wheel Brakes on Airliners

Wed May 30, 2018 5:06 am

Modern airliners seem not to have nose wheel brakes. It seems that adding nose wheel braking would reduce landing distance, reduce takeoff distance (because that distance is determined in part by the ability to stop after an engine failure), but possibly add weight.

Those seems like a reasonable trade off.

Has any airliner added brakes to the nose wheel?
 
jetmatt777
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Re: Nose wheel Brakes on Airliners

Wed May 30, 2018 5:12 am

The main wheel brakes are effective enough....

In the words of the great SlamClick. The last thing he’d see after applying maximum brakes was the paint on the fuselage flying past the cockpit window.
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Areopagus
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Re: Nose wheel Brakes on Airliners

Wed May 30, 2018 5:20 am

Not much weight is on the nose gear, so not much braking power would be available. But if it were, it would reduce stability- the reason planes switched to tricycle gear in the first place.
 
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FredrikHAD
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Re: Nose wheel Brakes on Airliners

Wed May 30, 2018 5:52 am

Surely with modern electronics, nose gear brakes could be controlled to avoid stability problems (if they do exist, which I’m not so sure about). Manufacturers must have other reasons for not adding them, and I’d guess the lack of requirement is their reason sine it also saves weight. The lack of requirement for them may be that there are already two separate systems for braking (reverse thrust being the other one). When braking hard, the NLG will be more heavily loaded and would also be more efficient in terms of brake action, so the question is relevant. Ask any motorcycle driver about that... In fact, when neded the most, the NLG would be the most efficient. Simple physics say that friction alone cannot give more than 1 G braking action by friction alone, but some grip is added to that on uneven surfaces like concrete or tarmac, making the total brake force vs. weight higher than just for friction.

/Fredrik
 
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Re: Nose wheel Brakes on Airliners

Wed May 30, 2018 6:21 am

Was an option on the 727. Not effective enough to offset added weight and additional maintenance.
 
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fr8mech
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Re: Nose wheel Brakes on Airliners

Wed May 30, 2018 7:01 am

Some B727's had them. I honestly don't recall a damn thing about them, except that I never had to replace one, even though I had replaced dozens of main wheel brakes. Which, anecdotally, tells me that they were not that effective.

Not only weight issue, but system complexity. Like I said, I don't remember anything about the system, but off hand, brake lines would need to be routed to the nose. A means of metering the brake pressure, including antiskid/autobrake logic must be provided. I suspect you would need a wheel well overheat/fire warning system in the nose well (did the B727 have that?).

I'm guessing the marginal improvement in braking, if there is one, does not out-weigh the disadvantages of installing them.
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strfyr51
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Re: Nose wheel Brakes on Airliners

Wed May 30, 2018 7:18 am

In 40 Years in Maintenance? I only saw ONE B727 with Nose wheel Brakes and that was when were were taking them OFF. I ws told their Weight as limiting the range of the airplane. And the airplane we took them off had been operated by Wein Air Alaska. So I Guess they needed them for the gravel runways in Alaska because they also had main wheels of 50X20 instead of the Standard 49X17's. And?
That I only ever saw on the Air Canada B727-200's and their brakes were HUGE!!
 
69bug
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Re: Nose wheel Brakes on Airliners

Wed May 30, 2018 7:48 am

Interesting.. so the left pedal operates the left brakes and the right pedal operates the right wheel brakes... how does the nosewheel brake come on/off?

bug
 
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kitplane01
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Re: Nose wheel Brakes on Airliners

Wed May 30, 2018 8:35 am

69bug wrote:
Interesting.. so the left pedal operates the left brakes and the right pedal operates the right wheel brakes... how does the nosewheel brake come on/off?

bug


I read that it comes on if the combined brake effort exceeds 50%, or either brake exceeds 70%. I also read other numbers. But I imagine that scheme is about right.
 
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kitplane01
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Re: Nose wheel Brakes on Airliners

Wed May 30, 2018 8:36 am

I read that the Convair airliners had nose wheel braking too.
 
Max Q
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Re: Nose wheel Brakes on Airliners

Wed May 30, 2018 9:47 am

69bug wrote:
Interesting.. so the left pedal operates the left brakes and the right pedal operates the right wheel brakes... how does the nosewheel brake come on/off?

bug



Good question, I asked the same about the center bogie brakes on the DC10 / MD11
and A340 / 300/ 600
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Max Q
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Re: Nose wheel Brakes on Airliners

Wed May 30, 2018 9:49 am

kitplane01 wrote:
I read that the Convair airliners had nose wheel braking too.




Correct, the CV 880 / 990 had nosewheel brakes


At Continental our Guam based B 727 aircraft had nosewheel brakes, these were removed if the aircraft was rotated back to the mainland for domestic service
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CosmicCruiser
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Re: Nose wheel Brakes on Airliners

Wed May 30, 2018 11:51 am

Best I remember Fedex removed them from the 727s because the cost out weighed the benefit.
 
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tb727
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Re: Nose wheel Brakes on Airliners

Wed May 30, 2018 12:43 pm

fr8mech wrote:
I suspect you would need a wheel well overheat/fire warning system in the nose well (did the B727 have that?).


Yes wheel well fire detection but no fire protection. Just put the gear down and then after they were locked down, back up momentarily to get the doors open.
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estorilm
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Re: Nose wheel Brakes on Airliners

Wed May 30, 2018 1:41 pm

I would imagine that the contact patch of a nose wheel tire is very small, relative to the MLG tires' contact area. Combine this with the weight & downforce available, and you get a relatively small amount of friction that can be applied. Even so, there are also space constraints - I don't believe the "stack" of brakes could be very large at all.
Then yes - add weight, complexity, reliability, and maintenance costs. No thanks. :)
 
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Re: Nose wheel Brakes on Airliners

Wed May 30, 2018 2:32 pm

Many airplanes have nose gear brakes to this day
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LH707330
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Re: Nose wheel Brakes on Airliners

Wed May 30, 2018 3:15 pm

Max Q wrote:
69bug wrote:
Interesting.. so the left pedal operates the left brakes and the right pedal operates the right wheel brakes... how does the nosewheel brake come on/off?

bug



Good question, I asked the same about the center bogie brakes on the DC10 / MD11
and A340 / 300/ 600

The 345/6 had brakes in the middle, while the 342/343 did not. IIRC the DC10/MD11 did have them, but don't quote me on that one.

Most of the weight is on the mains, with only a few percent on the nose gear. Even under heavy braking, the nose gear load doesn't increase appreciably because the CG is low relative to the wheelbase, so the forward change in weight vector would have a small impact.
 
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Re: Nose wheel Brakes on Airliners

Wed May 30, 2018 3:29 pm

jetmatt777 wrote:
The main wheel brakes are effective enough....

In the words of the great SlamClick. The last thing he’d see after applying maximum brakes was the paint on the fuselage flying past the cockpit window.


This is the core of the poodle. Airliners already have brakes that are more than effective enough. With maximum braking passengers will be breaking their noses on the seatbacks in front of them.
"There are no stupid questions, but there are a lot of inquisitive idiots." - John Ringo
 
Lpbri
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Re: Nose wheel Brakes on Airliners

Wed May 30, 2018 4:37 pm

One has to remember, with todays latest engines, with their very high bypass ratios, reverse is even more effective than ever before. Airplanes such as the MAX and NEO rely less on wheel brakes. Then you add the latest in carbon brake technology.
 
Max Q
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Re: Nose wheel Brakes on Airliners

Wed May 30, 2018 10:29 pm

tb727 wrote:
fr8mech wrote:
I suspect you would need a wheel well overheat/fire warning system in the nose well (did the B727 have that?).


Yes wheel well fire detection but no fire protection. Just put the gear down and then after they were locked down, back up momentarily to get the doors open.




Good memory TB


I remember that procedure now !
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GalaxyFlyer
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Re: Nose wheel Brakes on Airliners

Wed May 30, 2018 11:24 pm

The requirements for energy absorption in the rejected take-off at MGTOW means any modern-ish (jet era) has plenty of braking. Reverse thrust is not part of stopping calculations, so brakes are powerful.

GF
 
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Re: Nose wheel Brakes on Airliners

Thu May 31, 2018 7:44 am

CALTECH wrote:
Many airplanes have nose gear brakes to this day

Which aircraft have it? Reading the above posts, it seems the opposite? Happy to be corrected.
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Re: Nose wheel Brakes on Airliners

Thu May 31, 2018 12:50 pm

strfyr51 wrote:
That I only ever saw on the Air Canada B727-200's and their brakes were HUGE!!

Air Canada's first batch of 727-200s had nose wheel brakes. They were eventually removed and later deliveries were delivered without them.

But ... instead of short field capability being the aim, it was to keep all brakes cooler. The first 727s at AC were for use on Rapidair flights, YYZ-YOW/YUL. It was thought that after several shuttles back and forth, brake cooling might be an issue and the nose wheel brakes reduced the brake cooling time on the charts. If I recall, brake cooling time was reduced by about 20 minutes with nose wheel brakes installed and used.

Eventually, with 50-60 minute turn times being the norm, they were considered unnecessary. After a couple of years, AC did a study and found that nose wheel brakes were necessary in less than 1 in 2000 (or so) operations since introduction and decided to remove them. (AC never did have any "short field" 727 operations).

Let's face it. With brake temp guages, brake fans and carbon brakes .... brake cooling is less of an issue today.
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Re: Nose wheel Brakes on Airliners

Thu May 31, 2018 7:33 pm

Lpbri wrote:
One has to remember, with todays latest engines, with their very high bypass ratios, reverse is even more effective than ever before. Airplanes such as the MAX and NEO rely less on wheel brakes. Then you add the latest in carbon brake technology.


Hardly a factor. Braking on a dry runway doesn't factor reverse thrust.
MAX and NEO rely every bit on wheel brakes as their predecessors do.
And man are those carbon brakes powerful if need be.
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Re: Nose wheel Brakes on Airliners

Fri Jun 01, 2018 2:56 am

Interesting stuff. Were there any direction-control issues with using them?
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Re: Nose wheel Brakes on Airliners

Fri Jun 01, 2018 4:22 am

longhauler wrote:
strfyr51 wrote:
Let's face it. With brake temp guages, brake fans and carbon brakes .... brake cooling is less of an issue today.


Which aircraft (at AC for example) have integrated brake fans? I've only seen the button for them in photos of Airbus flight decks. Do the Boeing's have a button to turn the system on or is it automatic based on brake temperature monitors?
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fr8mech
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Re: Nose wheel Brakes on Airliners

Fri Jun 01, 2018 4:41 am

JAGflyer wrote:
Do the Boeing's have a button to turn the system on or is it automatic based on brake temperature monitors?


I don't know of any Boeings that have brake fans installed.
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kitplane01
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Re: Nose wheel Brakes on Airliners

Fri Jun 01, 2018 5:55 am

CALTECH wrote:
Many airplanes have nose gear brakes to this day


Errrr no. Not true.

Can you name a few examples?
Last edited by kitplane01 on Fri Jun 01, 2018 6:00 am, edited 1 time in total.
 
stratclub
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Re: Nose wheel Brakes on Airliners

Fri Jun 01, 2018 5:58 am

When I was supporting pilot training at BFI, I recall seeing a 767 with brake fans. IIRC it might have been a JAL or ANA. They may have been automatically controlled, because the flight crew was long gone when the fans turned off.
Last edited by stratclub on Fri Jun 01, 2018 6:03 am, edited 1 time in total.
 
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kitplane01
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Re: Nose wheel Brakes on Airliners

Fri Jun 01, 2018 5:59 am

Lpbri wrote:
One has to remember, with todays latest engines, with their very high bypass ratios, reverse is even more effective than ever before. Airplanes such as the MAX and NEO rely less on wheel brakes. Then you add the latest in carbon brake technology.


Starlionblue wrote:
jetmatt777 wrote:
The main wheel brakes are effective enough....

In the words of the great SlamClick. The last thing he’d see after applying maximum brakes was the paint on the fuselage flying past the cockpit window.


This is the core of the poodle. Airliners already have brakes that are more than effective enough. With maximum braking passengers will be breaking their noses on the seatbacks in front of them.


My understanding is that when computing takeoff and landing requirements, you are not allowed to consider reverse thrust. Better brakes allow the legal use of shorter runways.

You might not need maximum braking during normal ops, but their existence helps during an emergency, and allows the legal use of shorter runways during normal ops.
 
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Re: Nose wheel Brakes on Airliners

Fri Jun 01, 2018 6:14 am

Max Q wrote:
kitplane01 wrote:
I read that the Convair airliners had nose wheel braking too.




Correct, the CV 880 / 990 had nosewheel brakes


At Continental our Guam based B 727 aircraft had nosewheel brakes, these were removed if the aircraft was rotated back to the mainland for domestic service

I don't doubt that!! I was a USN P3C Flight Engineer and broke down In Kwajalien. I thought a part was going to be ferried in By another P3 and Lo and Behold a Continental B727 Taxied up, The Aft Airstair dropped and the Flight engineer got off and asked who the Flight Engineer Was.
I replied and he handed me a part,Waved Good bye, got back on his airplane and they took off. That was the first time I had ever seen an Air Micronesia, Jet.
I got to see the airplane again at Agana Guam and saw that it had Nose wheel brakes because their Mechanics were changing them out.
That was when I decided that when my tour was over I would become and Airline Mechanic and I did with United who now has the Guam operation flying all over the south Pacific.
 
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Re: Nose wheel Brakes on Airliners

Fri Jun 01, 2018 6:41 am

stratclub wrote:
When I was supporting pilot training at BFI, I recall seeing a 767 with brake fans. IIRC it might have been a JAL or ANA. They may have been automatically controlled, because the flight crew was long gone when the fans turned off.


I've never seen it on B767. It's possible that it's an option.
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fr8mech
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Re: Nose wheel Brakes on Airliners

Fri Jun 01, 2018 7:39 am

fr8mech wrote:
stratclub wrote:
When I was supporting pilot training at BFI, I recall seeing a 767 with brake fans. IIRC it might have been a JAL or ANA. They may have been automatically controlled, because the flight crew was long gone when the fans turned off.


I've never seen it on B767. It's possible that it's an option.


Just checked the B767 MMEL and Brake Cooling Fans are listed, so, they are an option on the B767, and apparently the B747, but not the -8. Learned something new. I guess none of the operators I've worked for took the option.
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7BOEING7
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Re: Nose wheel Brakes on Airliners

Fri Jun 01, 2018 4:49 pm

IRRC

Brake cooling fans were installed on the initial 777's delivered to Emirates but proved not to be necessary and were not ordered by any other airlines.

On the 747's the JAL SR's were the first to get them and ANA also had them on their "domestic" 744's.

On all Boeing airplanes, operation was automatic -- no flight crew input.


In the late 80's(?) nose gear brakes were being looked at for the 737 for a Brazilian airline to allow operation into/out of Santos Dumont in Rio during wet runway operations. Running the performance numbers it was determined that grooving the runway would be just as effective and a lot less expensive than certifying the brakes.
 
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Starlionblue
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Re: Nose wheel Brakes on Airliners

Mon Jun 04, 2018 3:35 am

kitplane01 wrote:
Lpbri wrote:
One has to remember, with todays latest engines, with their very high bypass ratios, reverse is even more effective than ever before. Airplanes such as the MAX and NEO rely less on wheel brakes. Then you add the latest in carbon brake technology.


Starlionblue wrote:
jetmatt777 wrote:
The main wheel brakes are effective enough....

In the words of the great SlamClick. The last thing he’d see after applying maximum brakes was the paint on the fuselage flying past the cockpit window.


This is the core of the poodle. Airliners already have brakes that are more than effective enough. With maximum braking passengers will be breaking their noses on the seatbacks in front of them.


My understanding is that when computing takeoff and landing requirements, you are not allowed to consider reverse thrust. Better brakes allow the legal use of shorter runways.

You might not need maximum braking during normal ops, but their existence helps during an emergency, and allows the legal use of shorter runways during normal ops.


Shorter runways are great, but adding more capability in all cases. just for a few marginal cases, is not what airline want to do. The added benefit of being able to use those shorter runways is (apparently) too small to warrant adding weight and complexity (cost).

Besides, why install more powerful brakes when we almost never use the full capacity of current ones? There's plenty for emergencies.
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stratclub
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Re: Nose wheel Brakes on Airliners

Mon Jun 04, 2018 10:30 pm

When we do RTO validation testing, the aircraft is at MTOW, TR's cannot be used and the brakes are worn to the maximum wear limit. If the brakes catch fire, the aircraft must be able to taxi/stand with out intervention from fire and rescue for 5 minutes.

https://www.youtube.com/watch?v=_g6UswiRCF0
 
Nean1
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Re: Nose wheel Brakes on Airliners

Wed Jun 06, 2018 1:27 am

I wonder when we will see more emphasis on peripheral electrical systems:
- taxiing systems by electric motorization of the front landing gear, possibly with some regenerative braking capacity
- high capacity lightweight batteries capable of emergency back-up, replacing RAT equipment
- solar panels at the top of the fuselage to recharge the batteries and provide some degree of air conditioning before the departure of the APU.
 
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Starlionblue
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Re: Nose wheel Brakes on Airliners

Wed Jun 06, 2018 2:06 am

Nean1 wrote:
I wonder when we will see more emphasis on peripheral electrical systems:
- taxiing systems by electric motorization of the front landing gear, possibly with some regenerative braking capacity
- high capacity lightweight batteries capable of emergency back-up, replacing RAT equipment
- solar panels at the top of the fuselage to recharge the batteries and provide some degree of air conditioning before the departure of the APU.


- Independent taxi motors might well be coming in the next decade.
- Batteries lightweight enough to do the job are still a long way away. Jet fuel has an energy density (energy per weight) an order of magnitude higher than batteries. Besides, you're carrying the jet fuel already.
- Solar panels could certainly could power the air conditioning and recharge the batteries, but the weight penalty makes it not worth it, at least with today's panels.

If I had to guess, I think we'll see the solar panels before the batteries, but neither one is really on the horizon at this time.
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BoeingGuy
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Re: Nose wheel Brakes on Airliners

Wed Jun 06, 2018 5:11 am

fr8mech wrote:
stratclub wrote:
When I was supporting pilot training at BFI, I recall seeing a 767 with brake fans. IIRC it might have been a JAL or ANA. They may have been automatically controlled, because the flight crew was long gone when the fans turned off.


I've never seen it on B767. It's possible that it's an option.


Some older 777s had it as an option. Boeing stopped offering Brake Cooling Fans around 2000.

I wasn't aware the 767 had it as an option. It's not offered now, but may have been before my time.
 
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Re: Nose wheel Brakes on Airliners

Wed Jun 06, 2018 5:15 am

Lpbri wrote:
One has to remember, with todays latest engines, with their very high bypass ratios, reverse is even more effective than ever before. Airplanes such as the MAX and NEO rely less on wheel brakes. Then you add the latest in carbon brake technology.


I don't think this is correct. Older airplanes reversed hot gasses too. Further, to my understanding some airlines only go above idle reverse in an emergency.

I'd say that airplanes rely more on wheel brakes now.
 
BravoOne
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Re: Nose wheel Brakes on Airliners

Wed Jun 06, 2018 9:57 am

BoeingGuy wrote:
Lpbri wrote:
One has to remember, with todays latest engines, with their very high bypass ratios, reverse is even more effective than ever before. Airplanes such as the MAX and NEO rely less on wheel brakes. Then you add the latest in carbon brake technology.


I don't think this is correct. Older airplanes reversed hot gasses too. Further, to my understanding some airlines only go above idle reverse in an emergency.

I'd say that airplanes rely more on wheel brakes now.



You are correct, and the idle reverse thrust issue is driven mostly by noise abatement issues, mostly during night time hours.
 
Apprentice
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Re: Nose wheel Brakes on Airliners

Mon Jun 11, 2018 7:32 am

kitplane01 wrote:
CALTECH wrote:
Many airplanes have nose gear brakes to this day


Errrr no. Not true.

Can you name a few examples?




Hi: Nose wheels brakes, today are very simple, just a Brake Pad that act against a caliper, acted by Hydraulic Pressure. Pressure will be directed automatically by a valve, when plane is in the air and landing gear is selected “up”
There are not designed to help stop the plane, but, to stop nose wheels rotation, when Landing Gear is on transit to upper position. These way, nose landing gear vibration is controlled.
For Main Landing gear, this function, (stop wheels’ rotation when landing gear are in transit to upper position), is acomplished by a valve thath route hyd pressure to normal brakes with a/c on air and L Gear selected on.

This function was performed by pilots in turboprop and older a/.c by pumping one- twice the pedals when wheels were “lin transit”. Today, as soon as aircraft go into “air” mode, crew pedals are “desconnected” from brakes.

Rgds.
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Re: Nose wheel Brakes on Airliners

Mon Jun 11, 2018 3:18 pm

Apprentice wrote:
Hi: Nose wheels brakes, today are very simple, just a Brake Pad that act against a caliper, acted by Hydraulic Pressure. Pressure will be directed automatically by a valve, when plane is in the air and landing gear is selected “up”
There are not designed to help stop the plane, but, to stop nose wheels rotation, when Landing Gear is on transit to upper position. These way, nose landing gear vibration is controlled.


What modern aircraft has this? Seems needlessly complicated, when nose wheel snubber pads do the job, rather well, without the complexity and weight of a brake system.
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stratclub
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Re: Nose wheel Brakes on Airliners

Mon Jun 11, 2018 4:47 pm

fr8mech wrote:
Apprentice wrote:
Hi: Nose wheels brakes, today are very simple, just a Brake Pad that act against a caliper, acted by Hydraulic Pressure. Pressure will be directed automatically by a valve, when plane is in the air and landing gear is selected “up”
There are not designed to help stop the plane, but, to stop nose wheels rotation, when Landing Gear is on transit to upper position. These way, nose landing gear vibration is controlled.


What modern aircraft has this? Seems needlessly complicated, when nose wheel snubber pads do the job, rather well, without the complexity and weight of a brake system.

Boeing and Douglas airplanes don't have nose gear brakes except for a very few B-727's. For other manufacturers I would have to make something up like I suspect the Apprentice did. The anti rotation snubbers are pretty standard from what I have seen on the Boeing and Douglas aircraft. Pretty simple in operation. Nose gear retracts and the tires contact the snubbers and stop rotating.

Image
 
Max Q
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Re: Nose wheel Brakes on Airliners

Mon Jun 11, 2018 11:56 pm

Pointless to have nosewheel brakes just to stop the wheels rotating prior to retraction, I think that’s a fairy tale


As stated that’s done with snubbers
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Caryjack
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Re: Nose wheel Brakes on Airliners

Wed Jun 13, 2018 9:25 am

Max Q wrote:
Pointless to have nosewheel brakes just to stop the wheels rotating prior to retraction, I think that’s a fairy tale


As stated that’s done with snubbers
For sure.
Perhaps some don't understand the need for brakes on MLGs after takoff, what with those massive rotational gyro forces at work.
Just curious, is someone able to say the weight of of the twelve MLG wheels on a B-777? I think they spin at 140 MPH or so...lots of energy.
Thanks,
Cary
 
Apprentice
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Re: Nose wheel Brakes on Airliners

Fri Jun 15, 2018 11:41 am

Good Morning, as explained before, only function of nose wheels brake is to stop nose wheel from rotate when entering NG Whel..
Snuber Pads do almost same function and are less costly, but they are able to stop the wheels, when NLG is almost completed retract.
I have never seen snubers for MLG, and they, been bigger and on more qty that nlg, also need to be stopped...
Hydraulically that is very simple: airplane logic air-ground, on air. LG handle to up. hydraulic pressure bond to raise LG, is also diverted to brakes, who are acted (braking) and after several seconds, this part of system is deenergizad and no more braking action. I repeat, this take time, at the begining of Gear Up, stopping wheels rotation and vibration at the very start.
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CALTECH
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Re: Nose wheel Brakes on Airliners

Fri Jun 15, 2018 10:52 pm

kitplane01 wrote:
CALTECH wrote:
Many airplanes have nose gear brakes to this day


Errrr no. Not true.

Can you name a few examples?


Errr yes. Very true.

KC-135, 727, 737, 757........

How do you think the nose wheels stop spinning after retraction ?

And Boeing does call them Spin Brakes. Can't remember what Airbus calls them, something like De-spin Brakes.

Back in 1985, took the nose gear hydraulic brakes off of the Air Micronesia birds as they came in for HMVs at LAXMX Base. Back then, it was weird seeing the nose gear without hydraulic brakes after we were done with the Mod..
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CALTECH
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Re: Nose wheel Brakes on Airliners

Fri Jun 15, 2018 11:02 pm

Caryjack wrote:
Max Q wrote:
Pointless to have nosewheel brakes just to stop the wheels rotating prior to retraction, I think that’s a fairy tale


As stated that’s done with snubbers
For sure.
Perhaps some don't understand the need for brakes on MLGs after takoff, what with those massive rotational gyro forces at work.
Just curious, is someone able to say the weight of of the twelve MLG wheels on a B-777? I think they spin at 140 MPH or so...lots of energy.
Thanks,
Cary


I would have to check, but IIRC each wheel assembly weighs somewhere around 400-500 pounds.
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fr8mech
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Re: Nose wheel Brakes on Airliners

Fri Jun 15, 2018 11:47 pm

Apprentice wrote:
Good Morning, as explained before, only function of nose wheels brake is to stop nose wheel from rotate when entering NG Whel..


No. On the B727, the nose brakes were part of stopping the aircraft. It was found in later models that they were not needed.

All* modern aircraft use snubbers or spin brakes to stop the nose wheels. The main wheels are stopped using the main gear brakes by the gear-up command.


*I don't know of any that have them, but there may be. Are there?
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