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Jan 20, 2016, 04:41 AM
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Dreamcatcher's Avatar
Hi !

The early versions of Ju-87 was fitted with retractable dive brakes - they was some kind of horizontal double bars located near the leading edge under the wing :






About the ju-87 flaps / ailerons (from wiki) :
"Junkers flap: a slotted plain flap where the flap is fixed below the trailing edge of the wing, rotating about its forward edge, and usually forming the "inboard" hinged section (closer to the root) of the Junkers Doppelflügel, or "double-wing" style of wing trailing edge control surfaces (including the outboard-mounted ailerons), which hung just below and behind the wing's fixed trailing edge.[13] When not in use, it has more drag than other types, but is more effective at creating additional lift than a plain or split flap, while retaining their mechanical simplicity. Invented by Otto Mader at Junkers in the late 1920s, they were historically most often seen on both the Ju 52/3m airliner/cargo plane, and the Ju 87 Stuka dive bomber, though the same wing control surface can be also be found on many modern ultralights."

May be this thread can be useful for you :
https://www.rcgroups.com/forums/showthread.php?t=206908

Some picture of a french build (big size for a museum) :
http://faucheurs.forumactif.com/t931...-pour-le-musee

A video of the FMS Ju-87 ailerons hinges :
FMS Ju-87 Stuka - Crash and Goes! (4 min 53 sec)


And finaly some pictures of the Greatplane's solution (ailerons + flaps) :





Nice Ju-87 project - ( may be a bit too much dihedral - imho )

Congratulations !
Last edited by Dreamcatcher; Jan 20, 2016 at 05:03 AM.
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Feb 08, 2016, 11:39 AM
Bipes Rule!
RITTMEISTER's Avatar
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support


Man do i owe you one!!!!! Well done exactly what i needed. You really came through for me!!
RITTMEISTER
Feb 08, 2016, 11:52 AM
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dihedral


Quote:
Originally Posted by Dreamcatcher
Hi !

The early versions of Ju-87 was fitted with retractable dive brakes - they was some kind of horizontal double bars located near the leading edge under the wing :






About the ju-87 flaps / ailerons (from wiki) :
"Junkers flap: a slotted plain flap where the flap is fixed below the trailing edge of the wing, rotating about its forward edge, and usually forming the "inboard" hinged section (closer to the root) of the Junkers Doppelflügel, or "double-wing" style of wing trailing edge control surfaces (including the outboard-mounted ailerons), which hung just below and behind the wing's fixed trailing edge.[13] When not in use, it has more drag than other types, but is more effective at creating additional lift than a plain or split flap, while retaining their mechanical simplicity. Invented by Otto Mader at Junkers in the late 1920s, they were historically most often seen on both the Ju 52/3m airliner/cargo plane, and the Ju 87 Stuka dive bomber, though the same wing control surface can be also be found on many modern ultralights."

May be this thread can be useful for you :
https://www.rcgroups.com/forums/showthread.php?t=206908

Some picture of a french build (big size for a museum) :
http://faucheurs.forumactif.com/t931...-pour-le-musee

A video of the FMS Ju-87 ailerons hinges :
https://www.youtube.com/watch?v=4AN5DMJTiuQ

And finaly some pictures of the Greatplane's solution (ailerons + flaps) :





Nice Ju-87 project - ( may be a bit too much dihedral - imho )

Congratulations !
What will the too much dihedral do. It was a pain in the rear assembling the wing.
Feb 09, 2016, 03:33 AM
Warbirds Lover
Dreamcatcher's Avatar
Wing dihedral is used to increase the plane stability on the Roll axis (when the dihedral is "positive" - i.e. when the wing tips are higher than the wing root)

With a bigger dihedral, wings should return to "the horizontal" by themselves as soon as the ailerons stick will return at neutral.

The plane will be a bit more sensible to cross winds

The wing will not closely looks like the original.
Last edited by Dreamcatcher; Mar 29, 2016 at 02:50 AM.
Mar 28, 2016, 11:41 AM
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RITTMEISTER's Avatar
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dihedral


Wonder why these plans had so much Dihedral? or why did I follow them? I had a feeling it was much more than scale.
Mar 28, 2016, 06:58 PM
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rckamikaze's Avatar

Excessive dihedral on plans


If you are working from 1965 plans, full house , 4 ch controls were just being introduced by radio mfgrs. The added dihedral would make the plans suitable for both 3 ch & free flight. the offset control surfaces would not have been very effective with the modest power available from two stroke engines of the period.
Just an observation based on experience & common sense. ( both outdated concepts in the new millennia )

Out of watts, altitude & ideas
Apr 13, 2016, 11:24 AM
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[QUOTE=rckamikaze;34381404]If you are working from 1965 plans, full house , 4 ch controls were just being introduced by radio mfgrs. The added dihedral would make the plans suitable for both 3 ch & free flight. the offset control surfaces would not have been very effective with the modest power available from two stroke engines of the period.
Just an observation based on experience & common sense. ( both outdated concepts in the new millennia )

Rckamikaze
Thanks for the info! I am installing flaps and ailerons what do you mean about offset and the effectiveness?? This is turning out to be the toughest part if this build so far
Apr 13, 2016, 11:42 AM
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RITTMEISTER's Avatar
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Flaps or not


Should i not use flaps and tie flap to aileron ? Make third piece inboard a flap or fixed?
Apr 13, 2016, 12:39 PM
Registered User
rckamikaze's Avatar

Offset control surfaces


Modern designs have little or NO air gap along the hinge line. This makes even the smallest movement of the control surface more reactive. The Stuka uses OFFSET ailerons. Maybe flaps also, I don't have a pic handy. The large gap means the ailerons will be less effective per square inch, needing more area or greater deflection to achieve results. The problem is exacerbated at low airspeed.
The large amount of dihedral would help compensate for this at landing speeds.
AGAIN: my humble opinion as I understand it, I am not an aerodynamics expert.

OUT of WATTS, ALTITUDE & IDEAS
Apr 13, 2016, 04:45 PM
Warbirds Lover
Dreamcatcher's Avatar
i think i would use 1 light weight servo per aileron and mix them to use the aileron as flaps if needed.
Apr 24, 2016, 08:09 AM
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RITTMEISTER's Avatar
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Where can i get a white spinner bigger than 2" for a 3 blade prop and a prop bigger than 10 60
Apr 26, 2016, 03:20 PM
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painting


Just about there. COG made for some internal adjustments
Last edited by RITTMEISTER; Apr 26, 2016 at 03:26 PM.
Apr 26, 2016, 03:39 PM
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scale


I choose to make the Elevator larger for takin off in the grass. Keeps me from nosing over on take off. I also changed the outter portion of wing for a little more wing area.
May 04, 2016, 07:51 AM
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Ready to Maiden


Went for another paint scheme.
May 04, 2016, 08:03 AM
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kdahlhaus's Avatar
That looks sharp


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