Fairey Gannet AEW3

beautiful build sir.
looks fantastic.

Thats one hell of a design and build, very impressive, what scale is it to?

Thanks, its to 1/6th scale. (108.6" or 2760mm wingspan). As i said in one of my earlier posts the the goal is to get it flying within the 7.5kg limit. Quite a challenge but the calculations show it is doable.

Ralph just come across this thread what a great build your doing there the design and laser cut parts are great. I've been looking at the Gannet for a while now and have posted a test rig of the flap linkage on YouTube about a year ago. I also today put a short movie of a contra prop unit I've built (Fairey Gannet variable pitch Contra Prop). It's built for a 90" span model the props are 15" dia. Don't want to hijack your thread mate but thought you might be interested.

Windy

Hi Windy, thanks for your comments.

You're certainly not hijacking the thread. This is a community sharing their passion. I did a search and saw your flap mechanism. Very impressive. I think you have sorted it better than I have. I am still not 100% happy with my solution so happy for any advice. Feel free to chip in, all contributions welcome!!

You variable pitch contra system is a superb piece of design. Way beyond my capabilities. Awesome.

Why 90" wing span? Any particular reason?

OK Ralph. I have some info on the flap system on my PC which may help that I'll gladly share. The problem is I'm having problems with this site on my PC at the moment for some reason I can't click on any links the cursor just flashes rapidly between arrow and finger in a very small area of the screen and does nothing. I'm doing this from my iPad.

If I get that sorted I'll post it.

The problem with my flap at the moment is there is little mechanical advantage for the servo as it stands, in fact if you press on the flap it will drive the servo backwards. But nothing that can't be overcome I feel. This was just to prove the linkage really. Of course the two ball links would be replaced with a fixed length link. Just gave me a bit of adjustment.

The prop became a bit of an obsession but enjoyed the challenge most of the time and what ever happens glad I did it.

I've also built my own undercarriage.

Why 90", that's based on sound aerodynamic and engineering principles, i.e. "Seemed like a good idea at the time" and of course "suck it and see".

Windy

Hi Windy, its seems we are tackling a very similar project from different ends. I have started with the airframe and working out the mechanicals as I go and, may be wrong here, you have tackled the mechanicals first. I have yet to design the undercarriage so you are way ahead of me on that element.

It would be great if you would share your flap system if nothing else to validate my system. Thank you for the offer.

I went for the 108" wingspan size from a similar perspective. I like round numbers and 1/6th seemed better than 1/8th. The fact that I had 4.5 - 6 kW available also helped!! "You can get a plank to fly with enough power!!" [badass]

I've been working on the flaps today getting the linkages and torque tubes sorted. Thanks to Windy for sharing his flap design which confirmed my set up. Nearly happy with them, just a few more adjustments.

Here is a picture of a flap torque tube concept that i'm going to use. This is from a 1/6th Fairey Firefly.




But discovered a major 'up cock'.

The wing joining tubes are located in the wheel well and the gap between the tubes will not allow a scale 5.5" wheel to fit. I think i've got a solution. The front tube can move forward into the 'D' box section of the wing. But the rear tube can't go behind the rear spar as it won't leave enough room for the flap mechanism! So current thinking is to do away with the rear tube and replace it with a vertical wing joining tongue, probably 1/4" birch ply, into a box fixed to the fuselage. Basically an extension to the rear spar.

Tony Nijhuis uses the same method on his 11' Lancaster model.
it works well.

Thanks Tony. I have the plans for that. I'll look it up.

pics from my 1342 Lanc build showing the wing joining method.

Thanks Tony, superb photo's. :kiss: Exactly what I was thinking of doing.

It has been a while since I last updated the build log. Work and a few days of flying have got in the way so not as much done as I wanted.

Today I made the Rotary Drive System (RDS) for the control surfaces. The main brass collars are a bought in item that are splined to fit Futaba splined servo output shafts. I bored them to take a square tube into which the actuator rod, which has a smaller square tube soldered on, will slide, The servo's are 10kg analogue, should be enough!!




I also replaced the motor drive shaft with a new home made longer one so that the separation between the contra props is to scale. Not a job I was looking forward too as the motor unit is £500+ so didn't want to get it wrong! All seems to have gone together OK. :woohoo:

very neat looking work there sir.

nice and tidy.

Well look what's back on the build bench!! Yes I know its been a while. New job and some decent weather to fly has interrupted the build. I did say it was going to take a while!

Well today managed to sort the rear formers below the tailplane. Had a lot of trouble getting the shape right. With a bit of jiggery pokery I'm happy with the out come. Also managed to temporarily fit the rudder RDS system.