Focke Achgelis Fa 330

kolibri282

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If you assume that the crosspiece is at right angles with the lateral axis and you want the lever arm to have the maximum possible length it has to be offset to one side, due to the different arcs through which it travels (10° degrees to one side and 6,5° to the other). As I said in my post this is just a guess. The lever arm seems to have a length of about 180mm which would not give a 10° degree travel to one side if the cross piece were at right angles to the lateral axis. If you rotate it such that the angle between lateral axis and cross piece is about 30° degrees the lever arm can be 180mm so if you rotate it a bit more you could do away with the offset.

When I threw the above at Google Translate it came up with the text below, containing two major errors (the first one is really silly but then, it's a tin can...;-) :

Si vous supposons que la traverse est perpendiculaire à l'axe latéral et que vous souhaitez que le bras de levier ait la longueur maximale possible, il doit être décalé d'un côté, en raison des différents arcs par lesquels il parcourt ( arc de 10° degrés su un côte et 6,5° sur l'autre). Comme je l'ai dit dans mon article, ce n'est qu'une supposition. Le bras de levier semble avoir une longueur d'environ 180 mm qui ne donnerait pas un degré de 10 degrés sur un côté si la traverse était perpendiculaire à l'axe latéral. Si vous le faites tourner de telle sorte que l'angle entre l'axe latéral et la traverse soit d'environ 30 degrés, le bras de levier peut être de 180 mm, donc, si vous le tournez un peu plus, vous pouvez éliminer le décalage.

Correcting the two would give:

Si vous supposez (ou si on suppose) que la traverse est perpendiculaire à l'axe latéral et vous souhaitez que le bras de levier ait la longueur maximale possible, il doit être décalé d'un côté, en raison des différents arcs par lesquels il parcourt ( arc de 10° degrés su un côte et 6,5° sur l'autre). Comme je l'ai dit dans mon article, ce n'est qu'une supposition. Le bras de levier semble avoir une longueur d'environ 180 mm qui ne donnerait pas un plage de pivotement de 10 degrés sur un côté si la traverse était perpendiculaire à l'axe latéral. Si vous le faites tourner de telle sorte que l'angle entre l'axe latéral et la traverse soit d'environ 30 degrés, le bras de levier peut être de 180 mm, donc, si vous le tournez un peu plus, vous pouvez éliminer le décalage.

Pour moi, la traduction Google semble très bien, Jean Claude, qu'est ce que tu pense?
 
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Jean - Claude

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10° on a side, 6.5° on other, is it not just a reference problem chosen ? In my opinion, the roll pivot 3 is in the plane of symmetry. Why would Focke-Achgelis want this asymmetry of entry? Perhaps Sigurd Sauer measured relatively to the hub parallel to the mast, instead relatively to the stick in the plane of symmetry.

La traduction par Google est très acceptable pour moi, Juergen
 
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kolibri282

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What I have been relating, Jean-Claude, are the results of a phone call, so there may well be some misunderstandings, without drawings some things are questionable. To make it very clear: I am sure Sigurd mentioned that the lateral travel was different one direction being 10° degrees and the other one 6.5°. My idea was that due to the lateral tilt of the rotor disk b1 lateral travel to the side opposite b1 must be larger, so the idea seemed quite ok to me. Sigurd did not mention any offset of the roll pivot, this was entirely my idea since a central pivot would make the lever arm a little bit shorter. Sigurd has promised to send me the parts of the FA-330 drawings that show the lateral controls by mid August. We should perhaps postpone further discussions until I am able to publish the drawings.
 

Jean - Claude

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I piloted gliders C800, Bijave, Castel 310, airplanes Piper J3, Jodel D117 and DR 220, Piper PA 28,
Total Flight Time
About 500 h (FW + ultra light)
I'm sorry for the mistake of side, Alan.
Due to the coning, the blade rises when it passes in front and reaches its highest point on the retreating side
Sans titre.png
 
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kolibri282

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One true rotary wing enthusiast has gone West. RIP
Since 01.05.20 I am retired and had hoped that Sigurd and I would have fun exchanging ideas and views on the Fa330, one unique aircraft.
Sadly it was not meant to be.
 

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Resasi

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That is sad.

It certainly was a fascinating and innovative piece of kit that no doubt probably contains lessons from the past. Certainly seemed to fly well...and pack up very compactly.

Can’t help thinking of the poor pilot if the U-boat were forced into a ‘crash-dive.'

I also wonder if any of you more erudite members posting on this particular thread would care to comment on my sudden possible brain fart, that with the latest materials and a small compact engine, utilising ideas from this machine it would be possible to design a compact light stow-able modern Ultra-light/Experimental.
 
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XXavier

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The rotor is of the conventional, fully articulated type. The machine could have been built with a two-blade teetering rotor, much simpler and lighter, but that type of rotor either wasn't known to the designers, or perhaps not yet invented...
 
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