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Martian01/01/2015 18:27:48
2529 forum posts
1163 photos


Here is what I propose to build ala mass build STOL

60" wingspan full span fixed slats full span flaperons (junkers style) they will be hinged to be in free air below wing trailing edge ,hopefully the servos will be within fuselage,wing will feature a deep chord and flat bottom,all flying aero fin no seperate rudder and upside down tailplane with roughly 50% elevator area oh and it will be leccy powered 4s lipo not decided on motor yet .build will depend on available funds

reg shaw01/01/2015 18:36:30
640 forum posts
562 photos

Sounds great, looking forward to thisyes


john stones 101/01/2015 22:16:20
11522 forum posts
1517 photos

Yes that one sounds interesting Martian "upside down tailplane " ?


Martyn K02/01/2015 15:00:22
5084 forum posts
3678 photos

Hi Martian

Now I have found it.. Watching..


Martyn K21/01/2015 09:20:23
5084 forum posts
3678 photos

How's it going Martian?


Martian21/01/2015 10:05:09
2529 forum posts
1163 photos

Hi Martyn not to well really I managed to get a chest infection since last posting and have been waking /sleeping for last two weeks getting over it now ,I have tried applying myself to some of the problems I need to overcome and made some templates will take pics and post an update in next couple of days

Martian23/02/2015 13:18:08
2529 forum posts
1163 photos

It's been a slow start but I have managed to build 2 wing halves and made a start on 1 slat

below drawing of tail section showing tail formers of 1/64th ply and balsa and a fibre glass sheet insert for the hinge surface,also the L shaped pieces are for the Junkers style flap or in this case flaperon they are made from a laminate of UVPC and 1/64th ply these are mounted in the wing at the trailing edge using a sandwich bond they form part of the flaperon hinge . Also you can see some of the wing ribs using a NACA 65019 profile .



top view of fuselage outline



side view fuselage and my feet on a chair


cross section of I beam spar which is 1/16th balsa and depron laminate this is my test spar it turned out really strong.


more later

Martian23/02/2015 17:46:49
2529 forum posts
1163 photos

a few more pics to bring it up to date




wing root,still undecided on how to join wing to centre section that will be fixed in place on top of cabin which in itself has a lot of glazing and I may have to make a brass tube support any way more thinking to do bottom sheet of wing is not in place yet until joining method is decided.


start on first slat it's fully built up and will be very light


john stones 123/02/2015 18:08:18
11522 forum posts
1517 photos

Coming on well Martian the wing looks very sturdy yes


Martian25/02/2015 10:42:25
2529 forum posts
1163 photos

Thanks John

yes I hope it will do the job it does seem very strong and also light and that is what I was aiming for .

Martyn K25/02/2015 10:47:53
5084 forum posts
3678 photos

That looks absolutely brilliant. Will it be at Greenacres?


Martian25/02/2015 10:53:30
2529 forum posts
1163 photos

Thanks Martyn ,am hoping so

Martian07/03/2015 12:48:19
2529 forum posts
1163 photos

Slow going but more progress

underside of slat showing formers some of the formers 4 to be exact are doubled this is to provide pockets for the acetate supports



Slat underside now planked visible is one of the pockets for the acetate support


wing leading edge test piece to work out position of slat support


Slat against the wing leading edge


This image shows approx gap of wing leading edge and back of slat


slowly building up a kit of parts ,below is 1 elevator and tailplane half plus wing half and flaperon


another view of same parts


slat in place for the pic also flaperon place under trailing edge it will be supported by hanging hinges just like a Junkers flap



flaperon profile



john stones 107/03/2015 21:49:40
11522 forum posts
1517 photos

Coming together nicely Martiansmiley


Martian07/03/2015 22:05:38
2529 forum posts
1163 photos

Thanks John

Martian13/03/2015 18:45:53
2529 forum posts
1163 photos

Introducing the Finder or Rudfin anyway no fin just an all moving aerofoil thingy


close up with glass fibre horn in place


Martian07/04/2015 10:57:12
2529 forum posts
1163 photos

For anyone interested here is my latest updates, still intend to finish for Greenacres

I'm building the fuselage in three sections below the rear section into the cave ,I,m using lightweight snakes in a pull pull layout elevator controls will be hidden as per full size and again as full size the rudder controls will be visible


tailplane and elevator (ignore the purple hue it's as a result of an attempt to use tissue) you can see the elevator hinges are hidden they consist of brass tube built in and a piano wire pin runs right through the connecting points are from glass fibre board as are the control horns.


this pic shows how the tailplane is mounted about 4mm above the fuselage top supported by 1/32 ply supports, a hollowed strake will hide the upper elevator horn. assembly cannot take place until after the covering.



below the other two sections in progress also the power box incorporating motor mount and battery box which will take a 4s lipo..working out the middle section is proving a bit long winded but I'll get there .. more soon


Martian16/04/2015 16:57:20
2529 forum posts
1163 photos

A bit more progress

U/C plate 1/8th ply with 1/8th ply backing and a brass bracket for the lower strut support



instrument panel and housing/coaming


instrument panel photo when glued in it will have a perspex cover


windshield will sit on the coaming and against 1/8th balsa cabin front


firewall with battery box aperture and nose leg mount


Nose leg showing brass wheel saddle and ali nose leg with piano wire insert


ridiculously large wheel 4" lightweight foam


mid section cabin area on it's gangly bush plane U/C stands about 7/8 inches above ground should put it in the upper atmosphere before it is airborne


Martian06/05/2015 11:08:32
2529 forum posts
1163 photos

Another update although there appears to be no interest ,I am trying to finish this for the RCME Greenacres flyin as it's part of this years mass build.

anyway enough drivel . below are the flaperon support legs


another view along the length


wing centre section this will be fixed permanently to the cabin


side view showing profile and the upvc box section to stop the wing rotating when slid in place


cabin section fixed in place also rudder and elevator servos in place..motor box/mount fitted and glued now to construct the split cowldscf0519.jpg


doors made and glazed not sure if I'm going to try to hinge or not may just use servo screws to fix in place


flaperon servos mounted on ply plate will connect to flaperons via ball joint and rods and a control pin will engage with the flaperon when wing is slid in place (confused so am I ) .plate will be screwed in place for access,there will also be an access plate on the upper fuselage


ESC mounted underneath the battery box/motor mount


Martyn K06/05/2015 11:36:52
5084 forum posts
3678 photos

This is great - lovely craftsmanship..

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