Landing Height System on a Jabiru 230

[Bruce Tuncks]

I have just got one of these in the mail. It only weight about 200 gms and it tells you just how high ( down to one foot ) your wheels are off the ground. You can see it working on the net.

My problem now is how to install it on my J230 plane, complete with microair radio. The radio has an aux input .( pin 6 of DB15 connector according to p14 of microair manual )

The manual says to only use a headset audio and so my plan is to use a resistor at least at first between the lhs audio and the radio. 

Does anybody know about these things? I would ideally like somebody who has installed one on a Jabiru 230 to help, but this may be asking for too much.

[Bruce Tuncks]

I am planning to connect the lhs to :

Red and yellow wires....   12 volt temporary supply.

Blue wire ( lhs audio output ) to pin 6 of micro-air radio.At first, this will be through a resistance box, with the initial resistance well over 1000 ohms.

Yellow wire ( the negative voltage wire ) to pin 11 or 12 on the micro-air .

I am quite scared of doing the wrong thing and causing smoke to appear.  References...  enginebridge Landing Height System 200-B manual and micro-air 760 manual.

[RFguy]

bruce

1st. make sure it is fused to something like you expect. perhaps 1 ro 2 amps max

2nd  - aux audio input according the the EARLY schematic I have is : there is not one. pin 6 is carrier detect.  CD - not compact disk, but carrier detect !

according to the socket - audio inputs are :

pin 1) dynamic mic-  (high sensitivity)

pin 2) electret mic (low sensitivity) 

 

according to the R13 book book pin6 is aux audio input -

according to the R6 book, it is "not wired"

 

which radio version do you have ?

 

the question is - which audio input are you using from your intercom - pin 1 or pin 2?

you can use the unused input for your audio input. but that might go to air, I dunno

 

you cannot hurt anythign with a 1k resistor- good idea.

what do you have as an intercom ?

 

 

 

 

 

[turboplanner]

Freelander

 

[facthunter]

Doesn't a breathaliser tell you how High you are?.  Nev

[Yenn]

When you get that low I wonder how much good a machine like that is going to be.

On my usual runway I would be getting heights like 10' 5' 3' 3' 2'1'T about half second intervals. The ground at the approach end of the runway is quite steeply up hill, then flattens out. The heights from the other end would be altogether different, due to its gentle downhill slope and then again a level runway would be different again. A bit too much for me to analyse quickly, but I seem to handle it OK using eyesight only.

[facthunter]

I can understand using  them (as a backup) when the U/C is 60 feet below you and 100 feet back, but for most of our little stuff you are just over the wheels.  Just put the effort in  to grease it on . It won't help you do cross winds much. Nev

[Yenn]

It won't make you a better pilot either.

[Bruce Tuncks]

I'll let you guys know as soon as I get to try it out.

But knowing if your mains are 2 ft or 1 ft above the runway does seem like useful information at this stage.

A big unknown is how the system will handle the approach over the scrub...   will it take the scrub tops or see through to the ground below?

AND, how will the technique of landing be altered to suit if it does work?

Right now, the setup is not on the plane ....  the easiest place to put it is  on the floor just behind the pilot's seat.

This means making 3 holes, the big one for the lidar to look through and the 2 smaller ones for the attach screws.

[turboplanner]

It will show you the scrub. If you want to try radar out, try reversing your car fast towards some bushes (that won't do any damage to your car). It's not that easy unless you slow right down, and with an aircraft if you slow the descent rigfht down you'll have a soft landing anyway.  With the J230 do you come in looking over the nose at the end of the runway?

 

[Roundsounds]

Wow, maybe you could couple this to the autopilot and teach it how to land the aeroplane too. How about an autothrottle too?

[Bruce Tuncks]

I need to fly so I can answer that question turbs.  I think so .

What I try and do is to get the mains at about a foot high and then try to keep them there, in other words I try and NOT land.

I reckon there is room for improvement in my judgement of the 1 ft high though. Sometimes the arrival is harder than I'd like.

I do remember a couple of late afternoon glider landings, where you could feel the wheel being spun up from the tips of the little weeds, as the speed washed off, and you fed in more elevator to keep this going.

 

[turboplanner]

34 minutes ago, Bruce Tuncks said:

I need to fly so I can answer that question turbs.  I think so .

What I try and do is to get the mains at about a foot high and then try to keep them there, in other words I try and NOT land.

I reckon there is room for improvement in my judgement of the 1 ft high though. Sometimes the arrival is harder than I'd like.

I do remember a couple of late afternoon glider landings, where you could feel the wheel being spun up from the tips of the little weeds, as the speed washed off, and you fed in more elevator to keep this going.

 

Don't tell anyone this, but I've had those same variations.