ahramin wrote:Easy auxbaton: leave the flaps down to help you slow down. Use brakes if required.
If you need brakes, I think we all agree that flaps up would be better. I still don't understand what he means, unless he never intends to use brakes.
No, we don't agree. If you need MAX brakes, then we all agree. But how often do you need max brakes? I honestly cannot ever remember a time in a King Air where I needed max brakes.
And if you don't need max brakes, then you are making it HARDER to stop the aircraft by retracting the flaps on touchdown, throwing away the drag created by the flaps (not to mention setting yourself up for what started this thread).
ahramin wrote: No, we don't agree. If you need MAX brakes, then we all agree. But how often do you need max brakes? I honestly cannot ever remember a time in a King Air where I needed max brakes.
And if you don't need max brakes, then you are making it HARDER to stop the aircraft by retracting the flaps on touchdown, throwing away the drag created by the flaps (not to mention setting yourself up for what started this thread).
It is not only for max braking, but up to a certain brake pressure (and the brake pressure will depend on the coefficient of lift and coefficient of drag with flaps up and flaps down). And this will also vary with the speed at which the plane is going through the air. I could get into the book and come up with a theoratical ratio, but I don't really feel like it right now.
My point is if you are not sure you can make it without brake, you are better off bringing the flaps up and use max braking. Aerodynamic braking from the flaps will not help you in a case like that.
AuxBatOn wrote:
My point is if you are not sure you can make it without brake, you are better off bringing the flaps up and use max braking. Aerodynamic braking from the flaps will not help you in a case like that.
Here's an even better thought.. If you're not sure you can make it without using max brakes, DON"T LAND THERE!! Seems like a simple concept, but as Doc and others have pointed out many times on this site, common sense seems to be in short supply these days!!
P.S. Sliding off the end of a runway at a slow speed usually does less damage than dropping a plane on its belly....
"My point is if you are not sure you can make it without brake, you are better off bringing the flaps up and use max braking."
-The reason is that I use brakes all the time because I need too, but not maximum brakes.
I agree with Ahramin's point:
"And if you don't need max brakes, then you are making it HARDER to stop the aircraft by retracting the flaps on touchdown, throwing away the drag created by the flaps (not to mention setting yourself up for what started this thread)."
In principle I agree with what Auxbaton is implying- You can stop an aeroplane in a shorter distance if you retract the flaps and use maximum braking (on many/most types). However, I suggest it is more difficult, unnecessarily inefficient as well as a bad habit to raise the flaps if you require braking below maximum.
That said, many of us fly different types and missions so I think flying procedures will rightfully be subjective.
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Last edited by x-wind on Mon Dec 28, 2009 1:16 pm, edited 2 times in total.
AuxBatOn wrote:
My point is if you are not sure you can make it without brake, you are better off bringing the flaps up and use max braking. Aerodynamic braking from the flaps will not help you in a case like that.
Here's an even better thought.. If you're not sure you can make it without using max brakes, DON"T LAND THERE!! Seems like a simple concept, but as Doc and others have pointed out many times on this site, common sense seems to be in short supply these days!!
P.S. Sliding off the end of a runway at a slow speed usually does less damage than dropping a plane on its belly....
You'd be surprised how much distance you can shave off when you actually use the brakes on a runway. Suddenly, you don't need that 8000' runway anymore, but that 5000' will do.
When I use the brakes, I always use them to max braking, for various reasons. The first one being it saves the brakes in the long run. The second one is that you are more likely to have hot brakes if you use light braking over a long distance versus using max braking over a short distance. We can talk about braking efficiency with hot brakes if you want
My landing distances are calculated so that I use max braking after landing. You bet I will land on a runway that the book says I can land on (with a little padding obviously).
Auxbaton, just so we are on the same page here, are you using carbon brakes or steel brakes? Have you flown a King Air or similar turbo-prop?
I have never heard of brakes on a King Air that were not steel. Running these brakes the way you suggest will lead to changing brakes and tires very often. In my opinion braking hard when not required is poor airmanship because of the extra wear and tear for no benefit.
You seem to be under the impression that if you leave the flaps down and apply heavy braking the wheels will lock up. This is not the case. You can brake very hard with the flaps down and not skid a tire.
I totally disagree with raising the flaps on landing (except to avoid damage on gravel/unimproved strips).
I will use the King Air as an example.
First, the AFM doesn't say to raise them.
Second, for reasons already stated in this thread (90% of my landings can be done with aerodynamic braking, idle reverse, and minimal wheel braking).
Third, not touching anything on touchdown prevents touching anything on touchdown (gear).
Fourth, if you ever have to go around after touchdown, having the flaps up can increase your stall speed by as much as 25 kts on the Kng Air.
Finally, when the props are in ground fine/idle reverse, I guarantee that the airflow behind them is anything but laminar. No smooth air means no lift. The area behind the props happens to also be the location of the flaps (If you want to, try to get airborne again after touching down and putting the props in ground fine. Let me know how high you get). Anyways, since there is no lift, it doesn't matter if the flaps are up or down, there is plenty of weight on wheels for effective braking.
AuxBatOn, Jesus H. Christ, you use maximum braking on every landing? I don't know why I respond to your posts, you must be trolling. I don't even know where to start with that one except that it reinforces the rumor that military pilots are hard on equipment. What are you flying that requires max braking to land in 5,000 feet? It must be a treat to grease it on and then push your toes to the floor, right to full anti-skid, and hold that posture until you come to a stop or the fire trucks pull up.
A couple of things you may want to consider are the fact that your landing distance is factored (if you are flying an aircraft that requires 5,000') and you have plenty of room under normal conditions for light braking, the AFM charts don't consider reverse (reverse with normal braking will give you the same stopping distance as max braking and no reverse), not all aircraft use carbon brakes, so you points about brake life and efficiency are untrue for the majority of steel brake users out there, and I was told that the brakes are the third most expensive operating expense behind fuel and engines, I can't believe that a few light taps on the breaks is harder on them than pushing them to the floor (and yes, I know all about the operating procedures of carbon brakes).
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You're not drunk if you can lie on the floor without holding on
Guys - don't forget what kind of aircraft AuxBatOn is flying - no props or BETA range on a CF-18 - it only stops with brakes (or the hook).
Military turbo-prop operators do not lock up the brakes on landing - we hardly use them - that's what BETA and reverse is for. On the Buff we would never touch them, 12' props slows the plane down just fine. On the King-Air, we use ground fine and tap the brakes at the end of the runway. That being said, in the case of STOL or max-effort, the appropriate use of brakes is warranted. I have landed the Buffalo at 39,000lbs in 800ft - skidding with locked brakes on gravel, tore the shit out of the tires - definitely not something to be done at all times.
If you need to use more than about 1/4 braking on a King Air, you either pooched the landing, took way too big a tail wind or, something pulled out on the runway in front of you. I have heard that sucking up the gear reduces your ground roll way better than leaving the flaps down. Is this true??
The issue here is as simple as this: don't be stupid, and don't let stupid people fly. No matter what the procedures a crew flies with, a stupid crew member will manage to throw a stick in the spokes.
I have flown King Airs, and the thought of mixing up the gear and flaps handles would be unthinkably dumb. They are located far apart, they feel different, and they have a different feel as you pull them up (you have to pull out on the handle to raise the gear).
I am of the school of belief that you should raise the flaps on touchdown through a certain speed (whether through previous mutual agreement or SOPs in a multi-crew environment) in order to maximize braking ability. I think that aerodynamic braking with flaps is minimal when compared to beta and reverse thrust, and braking will have a much more useful effect in the case that you would need them - so you should get into the habit of raising them every time, just in case.
But that's a different issue. The point is, how far should we take the modification of what may be more effective procedures to account for idiot pilots? I chose that word carefully, and I stand behind it. This kind of mistake is inexcusable, and if you don't feel so, perhaps you have no business commanding an aircraft.
bezerker, I don't slam on the brakes right after touch down every time, but I will delay braking until I need max braking to make the exit, or stop before the end. This is what I was taught from way back, both on the civilian side and military side.
AuxBatOn is referring to brake fade - which we all know occurs if you consistently ride the brakes instead of applying brakes firmly and then releasing.
SAR_YQQ, I have never heard of brake fade happening on an aircraft. I didn't think you could apply brakes long enough for this to happen. When or on what aircraft is this a concern?
Brake fade happens quite frequently on aircraft. I know of guys in my shop at work who had it happen to them before. Not that I want to go out and try it - given the correct circumstances, I am pretty sure it could be done with the mighty BE9L too.
AuxBatOn wrote:bezerker, I don't slam on the brakes right after touch down every time, but I will delay braking until I need max braking to make the exit, or stop before the end. This is what I was taught from way back, both on the civilian side and military side.
I don't even know where to start with this comment...I can't imagine any instructor advocating waiting till the last second and then using max braking..You must be flying for someone who doesn't care about the cost of replacing brakes. Using max braking every landing is very very hard on equipment and very uncomfortable for passengers on board. After flying several aircraft that had brake temp gauges I can say from experience that light braking over an extended distance creates considerably less heat than heavy braking. Ask guys that fly A/C with autobrakes what setting they use for regular operations. It's not max... Try using max braking going into Vegas on a hot day and you'll be sitting for waiting for your temps to get to a point where you are even able to taxi...
As for brake fade, I'd like to know exactly what aircraft this has happened in. In 19 yrs of flying 10-15 different types with weights from 2500lb-150000lbs and I have yet to experience it.
"Brake fade".....in an airplane? Only if you're doing doughnuts on the ramp. I've had it on a rally car. Never on an airplane. I'm hard pressed to believe there is so much disagreement on the subject of stopping an airplane???
You guys do have pilot's licenses, yes?
AuxBatOn wrote:bezerker, I don't slam on the brakes right after touch down every time, but I will delay braking until I need max braking to make the exit, or stop before the end. This is what I was taught from way back, both on the civilian side and military side.
Sorry to say, I would love to see you come fly the 705 RJ, if you do that in the commercial world. The passengers as they get off are going to give you a schooling in pilot finest. Now your on the F-18, I can't comment cause I've never flown.
In prop jobs, max braking is for, well if you have an emergency and only have 2000' to put it down. On the MU-2 I've still but it down using reverse and very light brakes only and cleared in about 2000 feet.
Doc can back me up, what is in in YPM from threshold to clearing half way down?? about 2000 feet.
Point is sounds like your one of those guys that will grease the shit out of a landing and destroy it by locking up the brakes.
flyinhigh wrote:
Point is sounds like your one of those guys that will grease the shit out of a landing and destroy it by locking up the brakes.
Again, I don't slam on the brakes right after landing (and there is no such thing as "greasing" a Hornet). When I need to brake, I will apply gradual application to max braking. Right to anti-skid.
bcflyer wrote:As for brake fade, I'd like to know exactly what aircraft this has happened in. In 19 yrs of flying 10-15 different types with weights from 2500lb-150000lbs and I have yet to experience it.
Well I had it happen to me because I assume I was (unconsciously) riding the brakes on landing. Brakes become spongy and braking effectiveness is greatly reduced to nil. It was in a Hawk, during the summer. I have seen hot brakes happen on the base here more than once during the summer.
I was always told that using max braking vs using lighter braking would reduce brake wear. That may be wrong, I have not researched it further, however it always worked for me and I never have to take into consideration passenger comfort.
flyinhigh wrote:
Again, I don't slam on the brakes right after landing (and there is no such thing as "greasing" a Hornet). When I need to brake, I will apply gradual application to max braking. Right to anti-skid.
I was always told that using max braking vs using lighter braking would reduce brake wear. That may be wrong, I have not researched it further, however it always worked for me and I never have to take into consideration passenger comfort.
I do have a question for ya, completely unrelated but related.
I have, as well as everyone noticed the the 18 is a well rocket with minimal wing to glide, with No reverse thurst. What do you ref at? average weight, on the thing I am going to imagine that you ref around 150? so yes I could see max brake, especially for your ops.
I do have a question for ya, completely unrelated but related.
I have, as well as everyone noticed the the 18 is a well rocket with minimal wing to glide, with No reverse thurst. What do you ref at? average weight, on the thing I am going to imagine that you ref around 150? so yes I could see max brake, especially for your ops.
We fly an angle of attack, not a speed. 8.1 AOA is what we strive for. Our Approach Speed is slower than the normal VRef (1.3 Vso normally, 1.22 Vso for us).
So, this speed greatly depends on weight. At a normal landing weight or 29000 lbs, approach speed would be around 125 according to the book. At a normal take off weight (2 external tanks + full internal fuel), it would be around 155.
FWIW, I always used that technique of max braking and as I said, nobody told me anything about it and I have never been told I was hard on the aircraft by the techs. On a long runway where I want make an exit, I will use firm braking, release for a few seconds, use firm braking, and so on, until about 40 kts g/s or use max braking to reach around 40 kts if there is an other aircraft on the runway behind me.
A bit off topic but I think the "correct use of brakes" discussion in the preceeding posts is a good example of the perils of the one size fits all solution. I would suggest the "correct" way to use the brakes very much depends on the type of brakes fitted to the aircraft. I think it is extremely important to understand the strenghts and weaknesses of the brake system fitted to your aircraft and to follow the POH direction and company SOP's and listen to the guys with lots of practical experience. Some aircraft demand hard application of the brakes, while others will do much better with a light touch
With respect to brake fade, the best way to experience it is to fly any light aircraft with those horrible old goodyear brakes. A few hard applications and the bottoms of your shoes, will provide more retarding force