Out of the box

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mikehallam
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Re: Out of the box

Post by mikehallam » Sun Dec 09, 2018 12:39 pm

Touche,

What Jodel DR1051 memories were aroused from deep down ! An Aural ASI sounding off at close to, but safely above, the stall on short finals.

That was from 20 years loving ownership which sadly ended in 1997 and I'd forgotten just how usefully satisfying it was to hear that squeaking at me as I came into the strip here over the trees.

It was a an adjustable vane switch mounted in the wing inboard leading edge - a simple but effective device.

Now could I somehow cobble up an equivalent for the Rans ?

With an Ali tube leading edge spar making any sort of hole in it is anathema, but any ideas would be gratefully received.

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Chris Martyr
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Re: Out of the box

Post by Chris Martyr » Sun Dec 09, 2018 2:11 pm

mikehallam wrote: adjustable vane switch mounted in the wing inboard leading edge - a simple but effective device.
Mike : How about one of them lollipop-stick type vane devices with a spring restraint . As used on 1930s type Pietenpols and things . With the tortoise symbol at the lower end and the hare at the upper end , plus all relevant stations marked-in , in between . :D
And if you could get some modern day device to beam it onto the lower part of your windshield , you'd have a kind of 'federated-multifunctional' version of a HUDIS display... :D :D
[Old Uncle Rog. would've beamed with pride at that one]

I had better stop . I'm becoming absurd without even having visited the pub yet .. :lol:
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Gerry Holland
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Re: Out of the box

Post by Gerry Holland » Sun Dec 09, 2018 8:58 pm

I have a sketch drawing Pietenpol vane type Airspeed Indicator if anyone wants to build one.
You used to be able to buy a kit at;
https://b28a4209-a-62cb3a1a-s-sites.goo ... edirects=0
or
https://sites.google.com/site/pietenpol ... n-packages

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Gerry
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mikehallam
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Re: Out of the box

Post by mikehallam » Mon Dec 10, 2018 2:42 pm

Thank you Gerry,

What I was actually thinking of was to replicate somehow a stall warning vane, very sensitive to the airflow direction change over the leading edge, operating an on/off contact a few mph - range say from 30 to 25% - before normal stall.

Then, as I now recall my Jodel used to do beautifully, on 'finals' one gets an aural speed indication and therefore can keep looking forwards e.g. at the gap in the hedge.

mike hallam.

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Gerry Holland
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Re: Out of the box

Post by Gerry Holland » Mon Dec 10, 2018 7:07 pm

Mike
Got it! Takes a time sometimes....
On a Europa I built I fitted one of these Stall Warners. It was retrofit but worked out well and worked.
http://www.lightaircraftassociation.co. ... %2061b.pdf
Has Aural warning.

Also had Proprietary Systems AoA fitted. Very good once calibrated which involved a 'bunt' to get negative 'G'. Has Headphone Aurul warning via Radio or Intercom.
http://advanced-flight-systems.com/Prod ... A/aoa.html
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Gerry
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mikehallam
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Re: Out of the box

Post by mikehallam » Tue Dec 11, 2018 6:25 pm

Thanks, that looks good so no need to re-invent that particular wheel - the web site indicates at least one was fitted to a Rans S6.

I've opened an e-mail discussion with "Sandalwood" to see how it all goes together on this a/c & particularly if one can avoid drilling the spar to install it.

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Re: Out of the box

Post by [email protected] » Sun Dec 23, 2018 9:25 am

Ian replies:
The subject matter covered by my “out of the box” article is very complex and to do it full justice would require the whole magazine, but editors being what they are didn’t allow me that much. I did a lot of thinking preparing this article (and the rest of the series) and hope that what I presented inspires critical thought rather than presents a solution. But I will comment on compasses. Yes, the location of the compass in my RV makes it vulnerable to electromagnetic fields. The phone and Garmin GPS don’t have any more effect on it than the wiring. If the compass is swung for the 4 points it seems to remain within 10 degrees when the various electrical functions are switched on or off. If I really wanted an accurate compass then a remote AHRS would be the solution, but I don’t think I do. I want to fly a ground track (as I suspect most of us do). That is a function of heading speed and wind. In a 450-mile flight how can I know what the wind drift is at whatever height I choose, ATC or the met conditions dictate. The compass does not give me a ground track and I don’t know the wind so there is no point of getting hung up about its accuracy. I might say it is still there because the ANO says it must be. I have 3 independent GPS systems on board with triple dissimilar SW all of which can display a compass. 2 of my GPS's can pick up at least 2 different satnav constellations and have batteries so are resilient. I have an inertial nav system in the form of my autopilot (solid state gyros so no precessing) and if I really want an accurate mag compass, I would use my iPhone on my knee. Yes, I am being deliberately controversial but, to my mind our hobby needs a shake to wake it up to what’s available around us. Just because the good ol boys in the string and fabric aircraft want to stay in prehistory, it doesn’t mean I have to do it to their antiquated rules. Mine is a different branch of the hobby. See next month’s LAA mag for an interesting take on AHRS and alternative flight instrumentation.
Ian Fraser.
Ian Fraser
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