Brakes (On or Off)

[Xnr]

This is a question for all the boys who fly wheels.

I would like to get your opinion and the reasoning behind your choice as it applies to this question.

You are on final approach to any area where a rolling landing is not possible. (i.e. rig, helipad, confined area, etc) Is the parking brake "on" or "off " on final approach.

Cheers

[Servo Jam]

Brake's on

Don't want to end up as shark bait !:cool: :D

Cheers

[bosher]

Or get covered in mud (or wet) at battersea!!!

PS Nose wheel lock on as well

[Nick Lappos]

Almost always I land brakes off, and apply them when downing the collective. If the deck is rolling or pitching, then brakes on during approach.

[Hummingfrog]

For N Sea ops the SOP is brakes on and nosewheel locked for rig/ship approaches. For airfields brakes off/nosewheel unlocked. In the old Whirlwind it didn't matter if the brakes were on or off!!!!
HF
:)

[heedm]

Brakes off, unless you really really can't roll at all.

Learned this while landing on a large pad at Max AUW. Building near pad blanked my headwind low final, decreasing performance shear, tried to slow it down with full intermediate, landed about 12 deg nose up (15max) about 15kts ground speed with brakes on. Couple chirps and then the nose really wanted to come down.

Hindsight, leave brakes on would have rolled very little.

Of course totally preventable if I realized what was going on earlier, but sometimes you don't realize these things. Brakes off gives you a few more options.

_______________


Here's a thought for everyone. When Winnipeg was flooding I was flying 6,000lb loads of sandbags from a muddy location to a distant dyke. Picked up load, wheels sank in mud. Trying to rip mains out of ground, I got very very close to dynamic rollover.

Question: Would the wheels have released more easily if the brakes were off?

[John Eacott]

Concur with Nick, I'll land with brakes off (but toes on the brakes, just in case..) nearly all the time. Also, nose wheel/tail wheel lock in, regardless of whether the brakes are on or off, to give directional stability when the collective is dumped. I've seen a Sea King rotate about 25 degrees, when the tail wheel lock was out, and it's not a pretty sight. Just as important on start up, as well. If it's a pitching or moving deck, or an offshore platform, local requirements come to the fore. Company regs (eg North Sea quoted before), Squadron SOP's, etc will dictate what has been learnt the hard way by others, and saves a lot of relearning. Odd points to consider are deck size and surface; if there's a net made of large diameter rope, you may be advised to leave the brake off, to allow the tyres to roll off the rope and into a hole. Some S76 landings, when the torsion bar between the mains push the other wheel down, need a bit of movement in the wheels which would not be there if the brakes were on.

HFrog, Whirlwinds with brakes. What will they think of next ;)

Matthew, Was your load internal, and if so, wasn't it an option to sling the things? I'll bite, my guess is that the brakes off would allow some rotation of the wheels, thus reducing the suction/stiction of the gear stuck in the mud, thus allowing a better chance of coming out of the gloop.

[heedm]

John,

Most of the time the sandbags were external (cargo net) and other things we hauled internal (people, dive gear, zodiacs, dog food for deer stranded on a little island....awwww cute).

I believe it was a full internal load when we got stuck well...turnover time a little slower and the load was a little bigger helped us sink more than usual. We fly faster and end up burning less gas with the internal load so for the longer distances we preferred the internal load.

[John Eacott]

Matthew,

OT, but IIRC you are flying the Phrog, have you seen this page? Interesting account from a Marine (http://www.f4aviation.co.uk/Oldstuff/h46/h46.htm)

[RW-1]

Matt,

I think not, for if you are picking them up out of the mud fighting the suction, whether or not they could rotate (breaks off) or not (Brakes on) wouldn't be a factor IMO.

Just my guess.

[ShyTorque]

I think that brakes off allows a smoother landing for the pax.

On the S-76 and other wheeled types I have flown, from a steady hover I feel that as the collective is lowered, the mainwheels need to rotate slightly backwards as the aircraft pitches nose down and settles vertically on the ground. If the wheelbrakes are on, all the pitching is done around the mainwheels once they make contact and the nosewheel seems to want to touch harder.

[heedm]

John, thanks for the link. Some new manoevres I must try. KIDDING. I couldn't believe the video of a quickstop in a H46, which was authorized then, but you don't see us flying like that now. The buttonhook would be good to see at the airshow (if you don't crash at the end), but that would be our only use for it.

I especially like the photo of a formation the same size as Canada's fleet.

http://www.f4aviation.co.uk/Oldstuff/h46/Formation.JPG

(Image found on http://www.f4aviation.co.uk/Oldstuff/h46/h46.htm check that site for all the other pics and good stories.)

[John Eacott]

Matthew,

Looked and looked, but can't see it. Can you post the link for the buttonhook video? TIA.

[heedm]

John,

I and my worst englich at werk again.

The video was of a normal quickstop done in an H46, seen on Discovery Channel a few years ago. It amazed me. I read the story of the buttonhook and thought that would be even more so. There is no video of the buttonhook as far as I'm aware.

BTW, the H46 in the video had the brakes off doing the quickstop into a tall grass field....keeping this on topic.

[Xnr]

What about as a safety measure in case of a single engine failure after LDP.

Wouldn't you want to stick at first ground contact.

We are talking about landing sites where there is any room to run it on.

Cheers

[Nick Lappos]

Xnr,

If you land with the brakes locked, the result would probably be tire damage (worn flat in a few seconds) and even loss of control (as the wheels skid, perhaps unevenly).

Best to land, get full weight on the wheels, then use the brakes with pumping action.

[donut king]

Nick,

Are you saying that the 76 brakes are strong enough to stop that machine" in it's tracks" during a single engine landing to a rig/ helipad.

Or, are the 76 brakes just for " handling" purposes during taxiing/ normal touchdown.

We once missed releasing the brakes and did a slow rolling CAT B landing. Honestly, the brakes did nothing to "dead stop' that aircraft nor did they grab and bang the nosewheel down as everyone thinks will happen.

To be fair, though, maybe the pressure was not at its maximum or we did not set it hard enough.

So, can you tell us if the 76 brakes are

a) for "handling" purposes only or

b) to actually "deadstop" that beast during an OEI CAT A landing.

I've heard arguments for both sides that make sense.

Thanks!

[Nick Lappos]

donut king,

The brakes in your case were probably not set very hard. It is certainly possible to stop the tire completely while moving forward if you press hard enough, and truly skid the tire. I have left a few dark black streaks to prove that.
With aircraft tires, a few skids is all ittakes to ruin the tire, and a long skid will thin the tire and rupture it.

Landing with the brakes on could also ruin the wheel in some helicopters. One very inexperienced pilot at Sikorsky bent the gear on an S-58 by landing with the brakes on!

In S-76, a smooth hard brake application, without skidding the tire, is assumed in the running landings we do for certification. They are not cosmetic brakes, donut king, they will stop you, and will skid the tire if pressed too hard. Take care to let them cool, or you will warp the disks and the Chief Pilot will have a discussion with you!

Don't expect automobile performance however. Cars have better wheels and brakes, and so they should, so comparivively a car's brake effectiveness is very mch more noticible.

[almost canadian]

Nick, what if you're landing on an elevated pad, about 70' in diameter (in a 76)? I can understand not setting the brakes if there is some room to roll, but in event of an engine failure just before landing on a small deck there would be absolutely no margin of error concerning brake application. I think having them on is one less thing to worry about.
Most checklists provide about 4 checks before landing to ensure that the brakes or either on or off.(post t/o, cruise, descent and landing checks.)
In a 2 crew aircraft, making a run on landing to run- or taxiway, with the brakes set is more a sign of bad CRM then PDM.

[heedm]

With brakes on, you get some deceleration from the tires, but you also get a nose down pitching moment. With OEI aerodynamic braking is still effective, more effective alone than braking is alone. The two together should give you maximum braking effort, but if you allow the nose to fall too much, then you may be relying only on the less efficient rubber braking or the amount of aft cyclic required to allow aerodynamic braking may get you into aft tip clearance problems.

Whether you have brakes on or off you should fly your profile to zero speed if the pad is small. If you can't do that, then I imagine just putting the mains on and keeping the nose up gives you more braking distance, since you may be able to put the nose over the edge...just don't go too far.

Sudden OEI short final to a pad I'd say overshoot is your best bet 99% of the time. Better to set up the approach you want than accept what you're doing.


Of course, all of the above was not type specific for anything. I fly an H46 where your fuselage attitude is a constant angle to the rotor planes. Thus, nose down is much worse for us...running on low speed with nose slightly up is best.

[polehog]

I think the question should be " Is it safe to set the brake in flight". As is the belief of someone in the air ambulance system in Canada.
It sounds as if all the people that have commented in this forum have no problems with setting the brake in flight.
It should be up to the PIC to decide whether the pad warrants it or not. In my opinion it would be unsafe to NOT have the brake on in some circumstances, like landing on the top of a tall building or tight pad out in the “briny blue”. A lot of pads are not level and can be quite tight so being prepared and having the brakes on for touch down could save some major embarrassment some time. As for the argument that you “square off the tires on landing if the brakes are on” maybe they should practice their hovering skills a bit.
;) ;) ;)

IMO

[Nick Lappos]

I would never make an intentional running landing with the brakes on. The danger of landing a helo with locked brakes and forward motion is high, as you have ceeded control of the aircraft at touchdown.

Unless the deck is moving, (in which case it is prudent to land with wheels locked) brakes are optional. One can lock the wheels, or learn to roll your feet to the top of the pedals prior to touchdown, use the brakes as the weight comes on the wheels. With that kind of coordination, you are a real helicopter pilot. If your company procedures say otherwise, or if you feel otherwise, more power to you, that's why they call you "Pilot in Command"!

[RW-1]

May I assume the same rules for wheeled heli's apply as to fixed wing in tapping the brakes prior to raising the gear?

(Also just tapping to avoid wobbling as wheels turn after liftoff, much more pronounced in fixed wing I'm sure but still posible here?)

this makes me remember a true story (fixed wing, but nice) about a C-12 (king air) crew that took off from Brunswick to P-Cola, they landed and immeadiately blew the mains upon touchdown.

It was discovered they never released the parking brake in brunswick, and actually slid their way to the runway and takeoff up there in the freezing weather.

I was about to throw in something along the lines nick just said, I mean, if we can come into a hover, or hit the brakes just after touchdown (zero speed termination to the deck) why would it matter in having them on prior and risking the negatives brought up?

[donut king]

Nick,

I understand everything you have stated and agree. I may not have worded my original question properly...so let me try again.

With OEI to a rig/ critical helipad with no run on space available..... brakes set..... committed through CDP..... as I flare, level, pull for touchdown.... WILL THOSE BRAKES PREVENT THE A/C FROM ROLLING FORWARD INTO SOMETHING?

I think they will but have not had an actual OEI event to prove that.( nor do I want to).

To be fair again, with the same parameters as above,but brakes off, is it better to flare...level....pull to touchdown.....then
jam on the brakes to stop the roll?

As for the potential flat spot created on the tire..... that would be the last thing if at all on my mind landing OEI to a deck/ critical helipad.

What say you?

Thanks!

[Nick Lappos]

I would suggest brakes off, then apply them after touchdown. You might waste a very few feet. Assume .3 second delay (that's slow) with 15 knots (that's fast) and you would roll an extra 8 feet prior to full brake application. If at 5 konts, its less than 3 feet. Small price to pay for full control at the touchdown.

Nick

[donut king]

Thanks for the explanation!

Much appreciated!


P.S.

AND ANOTHER THING!!!!

Just kidding..... Seeing that this forum is generating many questions for you and your Sikorsky gang, how about Sikorsky getting a forum going on the company website directed to us( pilots/ engineers/ training pilots......etc.)

Just a suggestion!

[Barannfin]

Hey guys just a quick question.

I have no experience with wheeled helicopters whatsoever, could someone just quickly tell me how the brakes are applied? I'm kinda at a loss, seeing as though our hands and feet are occupied.

[Lu Zuckerman]

I don’t know if this is applicable to the questions about S-76s and other wheeled helicopters landing on a moving and confined spot but this is the way it was in 1952. We had an S-51 (HO3-S) operating off of an Icebreaker off the Coast of Greenland. We had a 10,000 gallon tank that we were delivering to the Alert weather station on Ellesmere Island and sitting next to that was a Bell HTL-1 which seriously reduced the operating space on the flight deck. The Captain when breaking ice would never alter the direction of the ship to allow a stern approach or, stop the rolling and pitching. The pilots had to land athwartship and in the process try to miss the mast cable stays and a large hoist. All of this when the ship was moving at 90-degrees to the helicopter. During icebreaking the ship would both pitch and roll making the approach even harrier. The S-51 did not have conventional wheel brakes but it did have a parking brake. The parking brake was very ineffective in stopping a moving helicopter if it were set prior to a landing so in most cases the pilots would use aerodynamic braking but that made the landing even harrier because of the possibility of hitting the tail cone. Our braking system consisted of myself and two other crewmembers that would try to jam chocks under the main gear, while hooking up cable ratchet tie downs. God, I’m getting old.

[John Eacott]

Barannfin,

Brakes are applied (usually) by pushing on a brake pedal mounted at the top of each yaw pedal, with the toe of your foot, which often requires you to shift your feet up the pedal in order to get sufficient leverage.

Pedals are usually differential, giving the ability to use the brakes to assist turns whilst taxiing. Parking brakes are many and various, some requiring application of the toe brake, which is then 'locked' in place with the application of the parking brake, some have alternative parking brake independent of the toe brakes. Some helicopters have brakes for both pilot and co pilot, some are pilot only.

Most effective are those on skid helicopters, although they need a fair bit of power when taxiing......:rolleyes:

[Xnr]

Just had the opportunity to see a flight manual supplement for a S76C which was addressing the issue of Cat A vertical landing profile "zero speed". This profile is used for helideck landings "day only".

Interesting enough the first point mentioned in the procedure was "parking brake - set".

[Steve76]

Where did you see that?

[GLSNightPilot]

I just don't trust the parking brake that much. I land with the brakes off, & use the toe brakes, with however much pressure is necessary. Even OEI, with no roll permitted, I think I'd use the toe brakes instead of the parking brake, since I'm likely to jam all the brake I can, & as soon as I apply the toe brakes the parking brake comes off anyway. I trust my feet more than I do the parking brake.

[Xnr]

Steve, I am pretty sure that it is flight manual supplement #9 from the S76C flight manual. I only received a photo copy of the procedure page, so I am not positive.

[StevieTerrier]

What about normal lift off to / landing from the hover? Brakes applied or not? Cant speak for other types, but in the 222 the left main gear is on the ground first / off the ground last, effectively giving you a nice pivot point on which to make a fool of yourself.

I keep the brakes on because I reckon that makes things more stable at that critical moment, otherwise its like having castors on your skids, and who needs that??

But...I am quite prepared to be told I'm doing it wrong, so away you all go!

[GLSNightPilot]

I generally land from & pick up to the hover with toe brakes applied, to some varying degree. With the brakes totally off, the whole aircraft tends to roll backwards when the nose starts down & only the mains on, & I can't see behind me, so I don't want to roll. Offshore, I think it's important to have the toe brakes applied. I would never use the parking brake, though.

[Xnr]

It all depends on the type of take-off you are attempting.

All normal (helipad) take-offs should be done with the brakes released. You should also keep your feet off the toe brakes. Use accurate cyclic and pedal inputs to keep the beast in place.You will have a better feel for what the aircraft is doing and you will not drag a tire on the pavement if your cyclic position is off. Even a 222 will stay in place but takes a lot more pedal management. Thanks for the collective to yaw coupling in the S76 Nick.

If you are attempting a (helipad) take-off where your reject area is only the helipad below and you cannot afford any roll on the reject then the brakes should be set.

In short the only time the brakes should be set is in preparation for an OEI situation on takeoff or landing to an area where you don't have room to roll out.

Just my humble opinion. :)

Cheers

[flyer43]

Gentlemen,

I guess that some of you guys must be confusing offshore helicopter flights with carrier landings in the navy. Most offshore guys don't try to bury the helicopter in the helideck at speed - they tend to arrive at the destination in a low hover with zero forward groundspeed? Brakes on is SOP for all wheeled helicopters arriving offshore in the North Sea - Skids should be on for the remainder!!
There is a real difference in reaction between a squadie and an offshore worker to the way in which you present them to their working location.........

Happy Christmas to one and all.
:D

[donut king]

Brakes set for any CRITICAL helipad/ helideck....etc.

Brakes off to any NON-CRITICAL surface.

Brakes set if rejectting vertically to a critical pad/deck.

Brakes off if roll-on can be accomplished to the reject area.

I don't like swimming with sharks!!!!!!!!!!!!

D.K

[offshoreigor]

:p Definately, OFF. Unless you are ging to a Helideck. Ever forgot the brakes on a 76? Yikes, not fun!!!:eek: :eek:

Cheers, :p OffshoreIgor :p

[Xnr]

D.K.

I agree...... that's what I was trying to say in my post.....you said it shorter..... and better.

Cheers :cool: