Jabiru Toe Brake Mod

[sseeker]

Evening everyone,

 

It's something thats crossed my mind and has definitely been discussed around my airfield but I haven't managed to find a thread on here about it. Would anyone actually use the Jabiru toe brake mod if one was released? Differential brakes is something that would come in handy when you have to maneuver your aircraft around tight turns (in and out of parking bays!) Bindoon is quite spacious and there's not many tight turns so it's not an issue for me but going cross country it could prove difficult. Obviously you can't mod a training aircraft (not that I'm aware of) unless its been approved. So what does everyone think of it? Would you install a toe brake mod in your Jabiru?

 

-Andrew

 

 

[facthunter]

Toe Brakes in Jabiru.

 

Has to be a worthwhile idea. The current non-differential hand operated set-up is hardly state of the art. Cost and a small weight penalty would be the reason. Nev

 

 

[Bryon]

Where is Bindoon airfield?

 

I cant find it on Google earth

 

 

[sseeker]

Where is Bindoon airfield?

I cant find it on Google earth

-31.3388, 116.1893

Punch that into Google Maps/Google Earth.

 

Has to be a worthwhile idea. The current non-differential hand operated set-up is hardly state of the art. Cost and a small weight penalty would be the reason. Nev

You have valid point. I just worked out, our Jabiru weighs 307kg empty (no fuel) and weighs 401kg with full tanks (Avgas 100LL). So that leaves 134kg for Pilot+PAX, so I wouldn't want to use up anymore weight really.

 

 

[Bryon]

Thanks sseeker, I found it now

 

 

[compsci]

I own a J230 and would be delighted to install a toe brake modification.

 

I think that it is a safety issue beside being a convenience. Jabiru USA states

 

that there is insufficient room to install toe brakes. I don't think that's true.

 

I still push on my imaginary toe brakes in my J230.

 

 

[sseeker]

I think it's untrue as well take a look at the attached photo of a J160C cockpit (just grabbed it off Google.)

 

 

[AJW]

AvCom • View topic - Jabiru Dual Braking System

 

Look at this as well.

 

Ha ha, saw after the post " AvCom and BULL" This ain't no bull!!

 

 

[BigPete]

Lets go outside the circle.

 

What about dual lines from the current slave cylinder with some sort of switching device to choose which wheel gets the brake. Still hand operated but if we want it mainly for tight turns (and boy do we need it!) then it should work ok.

 

Application should be spring loaded to provide auto return to normal braking after use. Could be embarrassing if landing with only one wheel being braked.

 

Just my thoughts.

 

regards

 

 

[facthunter]

Brake Mod.(Jab)

 

BP don't you need to hold the throttle closed with your right hand, or have your hand on it when taxying?

 

Toe brakes are the general & simple way of doing it . ONE reservoir and

 

2 cylinders and I would recommend that standardisation is a good idea. The shuttle valve could fail. If you are only using it when manoeuvering at slow speed then that would not matter of course. They don't take up much room.

 

The system used on the Chipmunk would work OK. You apply a bit of brake the full application of rudder brings on the wheel brake. IF you apply more brake then the wheel brake actuates sooner. If you apply the brake fully then both brakes are fully on with rudder central, (In fact the brake prevents the application of rudder), and you can park it too.

 

I would prefer the toe brakes Nev.

 

 

[sseeker]

Facthunter in the Jabiru when taxiing if you leave your hands off the throttle the springs on the carby often bring the throttle in a bit, so you eventually get faster and faster (especially when backtracking) so it's always a good idea to keep your hand on the throttle to keep it closed instead of applying constant bursts of braking. That's with the Jabiru I train in, dunno about anyone elses.

 

 

[GraemeK]

Same with ours ....

 

 

[jetjr]

Boyd May used to sell a dual cylider setup, just had second lever beside original, easy setup, fairly $$ as I recall, had to get lever etc from Jab too.

 

Differential braking without pedal changes

 

JR

 

 

[facthunter]

throttle spring to "open"

 

Yes that is common to all the Bing CV carbs as set-up in Jabiru and Rotax 4-strokes. You are better to close the throttle fully than to wear out the brakes. This (as has been stated) requires constant pull to close. Nev

 

 

[BigPete]

Nev, my left hand operates the throttle while the right is hooked through the "Y" yoke and operating the hand operated brake. (J160C) :thumb_up:

 

Having never used toe brakes I guess I don't miss them. :big_grin: It's a real pain when back tracking after landing and your turn is as wide as the QE2.

 

"or have your hand on it "

 

I'm leaving this one alone (for now). i_dunnoi_dunno

 

regards

 

:big_grin::big_grin:

 

 

[Modest Pilot]

Jabiru USA use Matco Brakes, bit of a trap in that the ones they use are a heavier duty model to the Jabiru brakes recommended on the Matco site, and require a different bolt pattern on the axle/strut interface. It is possilble to fit toe brakes but it cuts into leg room that guys like me need, and have a think about servicing them; hope your partner is real small! Heard a rumor that the taildragger Jab's are fitted with them, does anyone know? The big advantage would show when landing in gusty X-winds.

 

 

[jaellio]

Any chance of a J160 with adjustable seats, guess not , Bet the guy/gal that designed the aircraft was about 6ft in height. After an hour in the aircraft, I'm starting to feel the pain , couldnt imagine 4 or 5 hours ....

 

 

[sseeker]

You should have adjustable rudder pedals.

 

 

[ianboag]

I have moved from a J200 to a J160. I'm normal sort of height and in both planes I just did "seat adjustment" with a cushion beneath and one behind .....

 

IB

 

 

[flie43]

Big Pete, I am right with you on the brakes. Bloody embarrasing having to shut down and get out to turn the girl around at the end of some narrow strip at a fly-in (Jimbour winery recently ) I don't think they need the complexity of toe brakes but a seperate lever as suggested that CANNOT be left on.

 

Terry

 

 

[BigPete]

Yes Terry, some sort of selector (spring loaded) to only supply pressure to one wheel would do it.

 

regards

 

 

[gas man]

This has been discussed before. The problem with Jabs is that the nose wheel is coupled directly to the rudder pedals and a very limited range of movement and therefore steering arc results.

 

GA spam cans must have some more complicated linkages because they are able to offer tighter steering without allowing excessive rudder movement.

 

In a jabiru tightening the turn with differential braking is going to skid the poor nose wheel laterally and produce associated wear and stress. I am not at all sure that this is a good thing to do.

 

Differential braking with a freely castoring nose wheel is used successfully on some aircraft but the geometry of the nose gear of Jabirus may not be suitable for this. The other plus of this arrangement would beless friction/resistance to movement of the rudder pedals - another problem with Jabs.

 

 

[Paul davenport]

What about fitting an automotive brake line locker to one side brake apply brakes turn on locker (12 volt operation) release brakes and that side stays locked on and you turn about the locked wheel Turn off locker and taxi on using brakes as per normal

 

 

[jabiruken]

My sp has differential brakes. They are heel operated, at first I was sceptical about the arrangement and planed to remove them after I purchased her. Not now as I have come used to them, directional control on touch down is where they excell. Only down side is no park brake..

 

 

[Roscoe]

Having come ftom many years flying Warriors to my Jab, I still automatically press the non existent toe brake when I want to stop, but I am slowly getting used to it, and like the other guy, control the throttle with my left hand and the brake thru the yoke mount.

 

I find this works very well when taxiing and with anticipation, very little braking is needed.