Topic: Armstrong Whitworth AW38 Whitley

I do like odd aircraft and particularly those that were either bad, ugly or quirky.

One of these I have always admired is the AW38. Particularly odd as it had a pronounced tail up, nose down sit in the air. Apparently this was due to this being the designer's first attempt at designing a plane with flaps, and just in case he added lots of positive incidence to the wing just in case the flaps were unsuccessfull!

Here is a picture of a fast low pass, just look at the sit, the crew must have had a screen full of runway!

I do like odd aircraft and particularly those that were either bad, ugly or quirky.

New toy per chance Stuey?

Crikey that really is a strange attitude for level flight.

be nice at about 15ft span with a pair of z38s

be nice at about 15ft span with a pair of z38s

Not quite, this will be 10' 6" and a pair of Laser 80s.....

Would that be the one built by Mike Trew and recently for sale on BMF?.  If so it flew very well at the Nats a couple of years ago but suffered from aileron flutter, causing withdrawal from the competition.

Yes, I met Mike yesterday, am in Bristol today and here it is in a spare garage .. So will be winging it's way back to Norfolk once I am done here.

Not much to do, on board glows, re-wire and batteries, free up the custom retracts, fit some engines, refix some horns and give a thorough going over.

The flutter was from the tail surfaces as they have a fair amount of slop from the linkages that go all the way along the fus! But I will check out the aileron surfaces too....

Oh, and the canopy/turrets needs some glazing..

I also purchased the Laser 80s from Mike. Each has MT stamped on the crankcase... Luvverly!

Would that be the one built by Mike Trew and recently for sale on BMF?.  If so it flew very well at the Nats a couple of years ago but suffered from aileron flutter, causing withdrawal from the competition.

YAY... look what I found..... And I calculated the wingspan wrongly, it's 118", not 126"

I spoke to Mike about him withdrawaing from the Nationals (it was 2006), it was the weather wind and rain that stopped any further flying, not the flutter..And this was the last time the Whitley flew...

 Do you suppose the idea was that with a full bombload and at its ceiling it would probably fly straight and level with a level fuselage?

I remember watching the model at the Nats (was it really that long ago!).  Definitely saw aileron flutter on the port aileron.  There may also have been elevator flutter but I did not see that.  The model flew superbly up until that occurence with the prototypical nose down attitude at speed.  Looked superb!

I remember watching the model at the Nats (was it really that long ago!).  Definitely saw aileron flutter on the port aileron.  There may also have been elevator flutter but I did not see that.  The model flew superbly up until that occurence with the prototypical nose down attitude at speed.  Looked superb!

Can't wait to see it in the air, but needs to fetlle this a bit first. There is play in the 'rons too, frise as well, I think they are diven from mini servos with small horns, so the play is magnified...

Can't wait to see it in the air, but needs to fetlle this a bit first. There is play in the 'rons too, frise as well, I think they are diven from mini servos with small horns, so the play is magnified...

I do hope you aint going to fit a commercial horn and external set up mate, it'd be a shame to spoil a very nice competition standard model. There must be a way of sorting the linkages retaining the 'scaleness'

Any pics of it all together yet?

Ian.

I do hope you aint going to fit a commercial horn and external set up mate, it'd be a shame to spoil a very nice competition standard model. There must be a way of sorting the linkages retaining the 'scaleness'

Any pics of it all together yet?

Ian.

I will clear it all with my "under 20kg inspector" first   

Any pics of it all together yet?

Ian.

Not yet, I am still in Bristol. I'll take some close ups of the "issues" when I get home and happy to take any advice on solutions...

Have checked on the rudder and elevator linkages again, there is bags of slop in there. Both rudders are driven by a bellcranks, linked to a 48" long 3mm pushrod and driven by a single Hitec HS85 servo.... The elevator is the same too. You can move the control surfaces around an inch without the servo horn even moving.

A 3mm pushrod?  Made of what?

A 3mm pushrod?  Made of what?

I'll check and take a photo in the morning, but I beleive it's carbon.

I would love to move the servo to the tail, but that's a huge moment arm and would require loads of ballast up fron AND would require some "sacrilidge" around the tail too so that's a no=no...

Any opportunity for closed loop (at least for the majority of the run down to the back and maybe a nice short stiff pushrod) ?

Keep it nice and scale like Stuey

I need to get some Flair Spectrum colours as this is what it was painted with, are they still available?

What is scary about this model is how light it is.... Each wing rib (every one in the scale position) is made from 20 separate pieces of balsa...    It feels like one squeeze in the wrong place would just collapse the whole structure......

I need to get some Flair Spectrum colours as this is what it was painted with, are they still available?

Yup,

Guess where 

Try clicking here

Charlie C

I need to get some Flair Spectrum colours as this is what it was painted with, are they still available?

Yup,

Guess where 

Try clicking here

Charlie C

Cooooooooooooooools.... Will make a list and pop in... 

Cooooooooooooooools.... Will make a list and pop in... 

Gissa a list and I'll sort it 

CC

It feels like one squeeze in the wrong place would just collapse the whole structure......

Best go carefully then Stuey!

This isn't the Whitley that used to tug gliders with the Arnhem Memorial Flight is it?

This isn't the Whitley that used to tug gliders with the Arnhem Memorial Flight is it?

No, it is too lightly built for that and no signs of "mountage"

Wasn't that a Halifax?

A 3mm pushrod?  Made of what?

Here we go, made of C/F......  You can see both rudder and elevator servos here mounted at the front end of the rear fuselage, this bit would join up with the front section just level with the wing trailing edge..

The slack isn't in the rod though, no play there or at the servos (Hitec 85MG), it's at the rear end, the elevator moves up and down without moving the pusrod, and the rudders move indepentantly of each other without moving the pushrod!

No access hatches are built at the back, so looks like major surgery to open up the rear and see how it can be tightened up... 

Neat building though by Mike eh?

Wasn't that a Halifax?

Sorry Stuey, just noticed that post.  No, was definitely a grossly under-powered Whitley towing a humongous Horsa glider, last seen disappearing through the sun-roof of a Vauxhall Cavalier at the RAF Halton show   It used to fly with two Dakotas as I recall?

Sorry Stuey, just noticed that post.  No, was definitely a grossly under-powered Whitley towing a humongous Horsa glider, last seen disappearing through the sun-roof of a Vauxhall Cavalier at the RAF Halton show   It used to fly with two Dakotas as I recall?

OK, there is no evidence of a tow hook, and this was only built to enter the 2006 Nationals. It has only flown around a dozen times. The fueslage is built so delicately that i think a towage would rip it apart. So no I don't think it is.

Did I say every rib is in a scale position, and is made up from 20 individual ;parts, each! 

How many parts is each rib made of Stuey?

Hi Stuey,
Looks a good project.

There was a large Whitley doing the show circuit many years ago.... in the region of 20 or so ( I think ) !
It must have been in the 15 foot mark and had a pair of petrol motors.  It was finished in Coastal Command colours.
It was around at the time of Steve Holland flying a large Catalina and Malcolm Gittin`s ? big Halifax, doing the Large Model Shows.
Anyone else remember it or have any photos ?
 Hope you get it fettled Stu...something a bit different too.
Regards, Dennis.

That big one was Andy Johnsons, he's still got it but its in need of some loving. It always had the right sit in the air too, but isn't in the same league as Mike Trews model which Stu has. Mikes model was built for scale competition and I remember it looked superb when I saw it at the Nats a few years ago.

Ian.

All that slop in the control system may be the result of flutter!  Mike would never have allowed that much free movement originally.

, but isn't in the same league as Mike Trews model which Stu has. Mikes model was built for scale competition and I remember it looked superb when I saw it at the Nats a few years ago.

Ian.

Yes this is a bit special, hence the catch 22, it needs cutting open to reveal the problems....... But don;t want to fly it with the slop as it is.

Mike demonstrated the slop before I bought the model and said it was like that when he built it, but as a slow flyer it was just a bit slow to react rather than a problem to fly....


Did I say each rib is made from 20 individual pieces?

Sorry Stuey, just noticed that post.  No, was definitely a grossly under-powered Whitley towing a humongous Horsa glider, last seen disappearing through the sun-roof of a Vauxhall Cavalier at the RAF Halton show   It used to fly with two Dakotas as I recall?

I remember that, I was there. About 1996?

Bonzey

Yep, that would be about it.  I'd only just got my 'B' and it was my first public show - the Moki 135 fell out of my Staudacher and was rattling around in the cowl still running!  Somehow I managed to land it and Ali was then seen chasing it around on on the ground before finally capturing and taming the beast!   .... I digress, this is about Whitleys lol

Right, went towards the tail unit with a scalpel last night, pondered for 15 minutes, got frightened and then started building the flaps for the Typhoon...

Gissa a look before ewe cut any holes in it.

CC

Well, spent the evening disecting the Whitley.... This involved cutting access holes on the underside of each stab halve under the rudders and a third hole in the centre. I am going to upload some YouTube clips to show you the problems...

Not really one big problem but lot's of little ones.... Back in a moment... 

YouTube is simmering away. Forgot to mention that if you unscrew the two tail lights then this releases the rear turret and you can see some of the linkages....

Elevator joiner can be seen running along the stab trailing edge and with the offest horn.
This allows ...
1) the whole assembly to move up and down when the pushrod is driven
2) each half to flex easily against each other
3) the rear portion of the elevator pushrod flexes up and down whilst it moves
4) And grabbing the elevator at each hinge you can move the leading edge of the elevator up and down by 1/4" !

The Rudder horn disappers into the stab.... But it moves side to side before it starts to turn

First video showin the flexing in the elevators and linkages, the movement in the elevators demonstrated does not move the elevator servo at all....

<a href="http://www.youtube.com/watch?v=0WaTrSFuWqg" target="_blank">http://www.youtube.com/watch?v=0WaTrSFuWqg</a>