Westland Whirlwind #3

Yes the full size was an interesting aircraft, the radiator shutters where interconnected with the flap control, so on landing the shutters opened up automatically, the cooling system operated at the top end of the scale, so timewise sitting around with engines running was very limited. Another quirk was the fact that the fuel systems where "handed", being that the L/H wing tank only served the L/H engine, there was no interconnecting pipe between L/H and R/H tanks
Barry

So the day arrived to couple the flap and nacelles together, after all the brain ticking, bits of balsa strips pinned on the plan, to get the arc somewhere near correct, the nacelles where glued to the flap, after suitable drying time, movement was checked, and it worked, a slight bit of binding on the ribs opening/closing, but a few rubs with sandpaper will fix that.....YEA...am I satisfied? you bet :woohoo:
I think that the 2 10kg servos will do the job easily
So there ya have it

bootiful work sir.

looks like you have it sussed ok.

Please can we have an icon that says 'awed, stunned silence'!!!

Tremendous!
Is the outer end of the flap supported in any way?

Quorneng, thanks for the kind word, the flap is supported only by the pivot points on the bottom of the nacelles, hence my pinkies in the pic (just to hold it up), that is why I am pondering on guide rails or 'wear plates on each end. The nacelles keep it fairly firm ( end slop ) at the moment. I have had no issues with Whirly #2 flaps which operates the same way
Cheers
Barry

I am sure a modest wear strip would be fine - but it might cause a problem if the flap leading edge ever went beyond the trailing edge of the wing!
It looks like on the original the flaps were in a slotted position when fully extended so presumably they were on rails.

Yea Q, thats the way I see it too, there is hardly any info on the full size operation of the flaps, so I've tossed a few around in my head, but have not come up with a simple solution, 1 I think may work is to pin the l/e,on the ends, to a thin metal slotted track, with the same arc, so it can slide in it, Do have any ideas ?? or should I just leave it as is
Barry

A slotted track would be ideal but it would need care to ensure its geometry matched that of the nacelle arm.
From what I can deduce from pictures the flap ran on rails (looks like one at each end and two in the middle?). The flap motion appears to rotate about a point low down just inside the fixed part of the nacelle but as you say without detail drawings it is very hard to tell exactly how it all worked..
Then of course there were the Handley Page automatic leading edge slats (which were apparently were usually wired shut in service!) and the radiator leading edge shutter as well as the rear cooling flap. It must have seemed an inordinately complex aircraft at the time.

Q, looking at the full size plane and all of the plans, the nacelle seperation line is as I have done, the pivot point is as you explained, with the pivot point secured, as the nacelle folds out and down that seperation line gets longer because of the angle, hence the flap binds on the ribs. This can be OK on the full size because of the depth of the ribs and can be relieved, but not so on the model.
Remedies are :- 1 reduce that seperation line angle to keep the pivot point as per full size position
2 move the pivot point position and keep that seperation line the same
3 Make the pivot point shift down, on a seperate linkage
The choice I took was #2 [badass]
Yea the end rails will have to be on the same arc as the nacelles, but the good news is that the flap L/E only shifts down 12/14mm on its travel, which will not be too hard to install, butI feelthat the whole flap end may be better if it was also pinned to the rail, again this would look unsightly with the rail sitting out in mid air when the flap is closed. There is no way that I can "dream up" where it can be hidden. :huh:
The Youngman design would be OK, but to incorperate the 2 would be a real brain teaser
So there ya have it, sometimes I feel as if "is it all worth it" :S , but it should be effective
Cheers
B

Trying to picture the mechanism, what you could consider is to turn it 'inside out', and put the rail on the flap, and the pin on the wing?
I don't know of anywhere in the U.K that has a Whirly, or a wing, for you to go and look at.
You could try an appeal for info to the holders of the Westland a/c drawings,possibly BAE archives, now, to see if they could assist?

Eric, that is a possiblity (rail on flap), I enquired a few yrs back to Westlands, and they told me that all the drawings where destroyed after the war, it's a bit hard, here in Aus trying to contact people in Eng, ( time difference) so it's just a bit of "if it works ... use it"
thanks
B

Ive just email the Whirlwind Fighter Project, I'll see what they come up with
barry

You have probably already thought of this, but try the archives at your 'local' aviation museum, in Aus, and maybe the place in NZ where they built the Mosquito. Somebody must have a service manual lurking in a corner, somewhere.
Or maybe you could track down someone who actually maintained or flew them, down there, via the Auz air-force, although they will be getting rather thin on the ground, now!

I don't think the Whirlwind was ever based anywhere but in the UK.
Barry
Have you seen this drawing?
Item no 80 refers to the "Flap outer track fairing" so the track appeared to run at least partly outside the wing profile.

This drawing shows the flap fully extended and suggests the flap movement was such that the lower part of the movable and fixed elements of the nacelle remained in close proximity throughout the travel hence the circular contact line at that point.
My own guess is the flap moved just on its tracks and the two parts of the nacelle were not hinged or jointed in any way.

Yes it is remarkable that nothing survived particularly as the 5th production Whirlwind was returned to Westland's, civil registered and used a company 'hack' but scrapped in 1947?
Of course the magnesium skin on the rear fuselage would not have survived long term storage particularly well!

If there are any details hopefully the Whirlwind Project should have them!