Farman Biplane aileron query

Good points, John.

Thanks Rob, that was the control system I’d concluded from looking at the Cynet photos.

Taking another look at the original Farman image, it’s pretty clear the aircraft it about to be started, looks like a race or competition with the line on the ground. The prop is horizontal, with a man about to hand start it. There’s a man braced to hold the tail back, and one on each side ready (one braced, one not) to hold the lower booms steady.

Regards,

It’s quite clear that on the original photo virtually nothing of the fine piano wire rigging is visible. It must be there because that structure would not hold together without it! In fact the guy at the back is trying to have the tailplane away. The top ailerons are drawn down from their extremities hence the control horns are only on the lower aileron to give the required leverage with cables to the leading edge of the lower plane.

John

Purely from memory, I think the lower ailerons are pulled from below and the bungees are attached to the top of the top wing ailerons.

Very interesting about the Hawker Cygnet. But I bet they were sprung the other way. By that time aileron differential was in use and more up than down was common, to reduce adverse yaw. De Havilland had a system that gave all up and virtually no down. I’m guess the Hawker did the same, but by a different method. Anyone know?

Jim

James, the Hawker Cygnet’s got bungee sprung ailerons.

Hi John, I wasn’t aware of the bungee option – fascinating. I’m assuming you’re not aware of any Boxkite application of this?

And yes, good to be back, and great to have been able to share the Boxkite then – and again, interwebzwise, now!

HP111 – that’s a good point, and you may well be right; though I don’t see the usual other evidence of retouching that such efforts usually show. Hmmm.

Regards,

Later some aeroplanes with ‘balancer ailerons had bungee cord tensioners fitted to the top sides so they did not droop at rest. Good the see James back. Thank you again for letting us see the Boxkite under construction on my last visit to Aus.

John

Perhaps it has been “painted out” so that for the purposes of the photograph it does not clash visually with the pilot. That might explain why there seems to be a very faint impression there.

Happy to help. There’s a Farman replica in Hong Kong airport, and my friend Joe May has photos on his blog Travel For Aircraft; in Denmark there’s a Gleiten, a Farman copy, which I have photos of. http://travelforaircraft.wordpress.com/2013/12/20/spirit-of-sha-tin-%E6%B2%99%E7%94%B0%E7%B2%BE%E7%A5%9E%E8%99%9F-walkaround-write/

The missing bit thing is one to watch. I think ‘your’ Farman is ready to go, and it’s just a trick of the light, but we have a photo of an Australian Boxkite with the pilot, helmeted up for the pose-photo, and the aircraft is definitely incomplete; so it does happen.

Good luck with the painting.

Regards,

Wow, that was quick! Thanks James, that explains it really well, I’ve been wondering for a long time exactly how they worked. So, obviously that port upper flap is there in the photo, in fact I agree, I think you faintly can see it. I guess I’d better add it to the painting, that could have been embarressing!
regards, Steve

Here’s a photo of the cable arrangement to the stbd lower balancer for the RAAF Museum replica Boxkite:

You can see the cable and guide and how it is slack when not under load.

For local references (I presume you’re in the UK) the Shuttleworth Boxkite has the original system, and I believe the Bristol City Museum example is set up likewise. As references to the Farman III ‘look’ they’re pretty good, though the Bristol was – and proven with a court case – ‘better built’!

In the image you’ve posted, the reflection of the upper port balancer is hiding it; but it’ll be there like the rest. I’m convincing myself you can just make out the rib shadows…

Happy to answer further questions!

Regards,

Aha. This is Boxkite territory! Most of the Farman III derivatives had essentially this kind of system. I’ll talk of the Boxkite, where they are called ‘Balancers’, not Ailerons, as that was how roll control was seen. There are control cables running from the stick to the control horns on the lower wing, via cable guide tubes (not pulleys) and the lower aileron/balancer is connected to the upper by further cables.

At speed, the surfaces trail under aerodynamic load (OK, they ‘blow up’) and the pilot can pull one side down, but NOT raise the other to achive a degree of roll. It is an incomplete cable ‘circuit’ as there’s no return cable to lift the opposite aileron. So while early aircraft had degrees of adverse yaw, the Farman boys had a whole range further to deal with.

More shortly.

Whilst I appreciate that the photograph is not of the highest resolution, I can’t see any control wires at all featured in it! Do I need better glasses or perhaps this is a staged photograph?