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Potentially stupid question...

E

ebrendan

I'm New Here
... Where is the Pitot tube on the RV-12? Is that it sticking out of the front of the spinner? If so, why is it there? Because the wings are removable?

Clearly I've never built an aircraft before. My father and I are considering starting an RV-12 kit.
 
How is the Pitot line routed from the spinner?

Hi all,

I do understand that the pitot tube on the -12 is in the middle of the spinner - Just how is the air line routed to the sensor or gauge? The spinner is spinning and so is the pitot? - how is this spinning state changed to a fixed state?

Thanks - Just wondering how they do it?
Jim
 
The pitot does not spin. The hole in the spinner in large enough, such that it does not touch the pitot tube. The propellor shaft is indeed hollow.
 
Hollow propeller shaft!

Hi Marty - Let's see if I understand this: The propeller shaft is hollow, so the fixed pitot tube runs through the propeller shaft to a sensor or tube fitting on the back of the gearbox? - ?
I have flown two aircraft with the Rotax 912uls (Sportstar & Dova Skylark), I was pleased with the power and ease of operation - I feel the Rotax will be a great little engine.

Thanks, Jim
 
ceuh1v said:
Hi Marty - Let's see if I understand this: The propeller shaft is hollow, so the fixed pitot tube runs through the propeller shaft to a sensor or tube fitting on the back of the gearbox? - ?
I have flown two aircraft with the Rotax 912uls (Sportstar & Dova Skylark), I was pleased with the power and ease of operation - I feel the Rotax will be a great little engine.

Thanks, Jim
Click to expand...

Hi Jim, I am not Marty but you got it right. Prop drive shaft is hollow all the way through the gearbox.

This is good for a number of other interesting setups:
1) Variable prop pitch control cable can enter here to mechanicly change prop pitch in flight.
2) On pusher type planes (Ultralights) they tow hand gliders and banners attached to a rope/cable system that attached through the prop thrust center line.

Me being in South Africa and not bound by the same Sport Pilot/Plane rules as you USA guys are seriously considering fitting a VP prop with mechanical adjustment in flight using that hole. Many 912 props on the market to do it.;)

Problem then is where to I put my pitot due to removable wings :D

Regards
Rudi
 
pierre smith said:
......Rudi, Rudi...in the wings, of course. A bit of plastic tubing to re-connect follows:)

Blue skies and tailwinds,
Click to expand...

Hi Pierre,

Ja I know, but I need a good interconnect then that will seal decently if you plan to take wings off often. I hope the RV12 wing has inspection hole covers so it can be done ala rv7 style, mounted on the spar flange. From the pictures I've seen so far it doesn't look like it...that will complicate matters a bit. Hence my question where?

Regards
Rudi
 
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what about a fuel line connection (both parts) for a Johnson outboard moter. THey seal well, and are easy to take apart.
 
Wasn't the prop of the ME109 driven by the hollow camshaft with the cannon firing through it and the spinner?
Plus ca change!
Jim
 
Line for airspeed

Hello
The outboard connecter is a good solution. But use a suzuki connecter instead because it's smaller,lighter,lasts better, and is cheaper!
Just use a short piece of shrink tubing to safe tie it. But don't burn the hanger down shrinking it.
And I use to work for OMC.
 
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Depending on the height, the vertical stabilizer can be another option for the pitot. The pitot on my Moni Motorglider was in the stabilizer. Of course the prop was only 34" in diameter. The pitot MUST be outside of the prop blast.
 
Mel said:
Depending on the height, the vertical stabilizer can be another option for the pitot. The pitot on my Moni Motorglider was in the stabilizer. Of course the prop was only 34" in diameter. The pitot MUST be outside of the prop blast.
Click to expand...

Actually Mel, it usually needs to be even higher than clearing the prop blast in level flight so that it is still out of the prop blast at very high Alpha angle of attack and full power (such as experienced in a power on stall). I have seen pictures of older T-18's (I think) that had them mounted on a mast above the vertical stab.
 
Colder Products makes a line of reliable inexpensive disconnect fittings.

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haven said:
what about a fuel line connection (both parts) for a Johnson outboard moter. THey seal well, and are easy to take apart.
Click to expand...
 
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