DFS - 230

[Orionis]

Quelques plans un peu plus serrés... Bonne construction!

[Jo Berg]

Bonsoir Mat,

Un tout grand MERCI pour tes photos.

Chouette de voir le planeur une fois en grandeur...

a +

Jo

(et bonnes fêtes!)

[Jo Berg]

Salut à tous,

Voilà, d'abord tous mes voeux pour 2011 et surtout de bons atteros...

Juste une photo pour montrer la suite des événements. Première moitié de l'aire terminée...

Bien à vous

Claude

[haju68]

Très beau modèle, et effectivement assez original...
Concernant la croix gammée, il me semble qu'en France sa reproduction est interdite sauf dans un cadre historique... Ce qui est visiblement le cas ici. Au Luxembourg par contre, je n'en sais rien...

Bonne construction....

[F-BDRO]

[Jo Berg]

Bonsoir à tous,

Voilà, Claude vient de terminer le DFS. Reste juste encore quelques babioles (ça s'écrit comme ça j'espère ;-) à installer (chapes, récepteur,...)

A plus pour d'éventuelles photos!

Bien à vous

Jo

[Orionis]

Joli camouflage, bravo!
Il me semble néanmoins que la croix gammée se trouve sur la partie fixe de la dérive, non?

[F-BDRO]

[F-BDRO]

Sur beaucoup d'autres photos, la croix gammée est floutée, pas moyen de voir où elle se trouve. Par contre, en principe, il ne vaut mieux ne pas le faire voler ou l'exposer en Allemagne...

[wingsoverk3]

Greetings from the Himalayas. I am building a DFS-230 scaled down to match RCM plans Junkers Ju-52. Build log is at
http://www.rcgroups.com/forums/showthread.php?t=1136629&page=11
If I may, I can post here also. My question is, the original DFS-230 had spoilers/airbrakes but I have not seen any scale RC build that have them. Is there a reason?
Cheers
Vik

[garifaldo]

Je suis tombé par hasard sur cette vidéo, qui à partir de 17.28 est largement consacrée aux planeurs allemands de transport de troupe.
http://www.youtube.com/watch?feature=player_detailpage&v=Xtlkdfbn8I4
Je ne suis pas fan, donc je n'y connais rien, mais ça m'a semblé intéressant.
A+

[VincentB]

Hi Vik,
Welcome to the forum great to have a visitor from so far

why not build spoiler? probably to simplify....
where are the spoiler/airbrake on the wings?

have you seen these 2 other links?
http://www.retroplane.net/forum/viewtopic.php?t=556
http://www.retroplane.net/forum/viewtopic.php?t=729

I have visited your website, interesting and exotic for us

[wingsoverk3]

Hi VincentB,
Thanks for the welcome. But I must say Orionis and JoBerg's builds are more impressive. The only evidence of spoilers/airbrakes on the DFS-230 are from the 2D drawings online. But DFS were known for using spoilers on the interwar competition sailplanes like the Reiher.

[VincentB]

zone more dark, airbrake? difficult to be sure...



what weather do you have? it's the mousson?

[wingsoverk3]

Yes, it's one of our wettest monsoons ever. My flying starts only in October-November when people start climbing Mount Everest and Kanchenjunga (60km from our airfield).
So I keep busy with my scratch-building:
http://www.rcgroups.com/forums/showthread.php?t=1918836
http://www.modelbouwforum.nl/forums/zweefvliegen/102115-groeps-bouwver.....an-60-a-18.html
http://www.aerodromerc.com/cgi-bin/yabb2/YaBB.pl?num=1371362726
Yes, I have that photograph also to help me with top hatch. Besides the outline drawing I have nothing else to indicate spoilers but as I said, DFS were known for spoilers in their designs. I'm installing them anyway.
Best
V

[wingsoverk3]

Greetings again gentlemen,
Work on the DFS-230 fuselage continues. I'm building the DFS 230 A-2 version which had dual controls and longer cockpit.













I have a question. In the build plans is what appears to be a trapdoor.
Anyone know what it is?




Best
Vik

[VincentB]

Please Vik, put photos only on the retroplane's server, not on extern hoster like photobucket, and with the right size 600px max, thanks
like explained here http://www.retroplane.net/forum/viewtopic.php?t=3808

it's not a system to release the landing gear?

[Walter L.]

Hi Vik,

you live in one of the most fascinating areas of our planet. I would like to visit your country, if I could....

Concerning your question I can tell you that the DFS 230 had spoilers on the upper side of the wing. In the book of Peter Ocker, who wrote and published a book about Hans Jacobs (who designed the DFS 230), there is a drawing which shows these spoilers. It is a drawing of Vince Cockett, who is a member in this forum....

Tomorrow I will make a picture of it and post it here.

Regards from Germany
Walter

[wingsoverk3]

Hi VincentB,
Gotcha WRT posting photos. My daughter does my IT-work, posting on forums but she'll be off to college in couple of months so I have to learn myself.
Hmmm, I think you're right, it's for the takeoff landing gear.

WalterL, I live in Sikkim which is between Nepal, Bhutan, China. Kanchenjunga is 50km or so west of one of the airfields I fly from. You are more than welcome to visit with one of your birds. I have a small hotel or two, be my guest.
I practice M/L range flying (in non-monsoon months) from Bulbulay Dara N 27° 22' 09.0" E 088° 37' 41.1"
http://www.paraglidingassociationofindia.org/pgfest2012/
http://www.paraglidingassociationofindia.org/pgfest2012/bulbulay-dara-flying-site.html
My own airfield outside bedroom. I replace the CFL with strobe lights during flying season

[Walter L.]

A very nice region...

Here the promised picture. It is from the book: "Hans Jacobs. Pionierleben im Flugzeugbau" (Pioneers life constructing airplanes) from Peter Ocker:





I hope this helps.

Regards
Walter

[wingsoverk3]

Thanks a ton. I was going to install the spoilers anyway but this is the extra validation needed.
Best

[wingsoverk3]

Fuselage is upright first time. RDF900 radio modem (900 MHz) for telemetry will be on top of fuselage aft of wing so the heatsink will be exposed to slipstream.

[wingsoverk3]

Another DFS-230 with no evidence of spoilers.

[wingsoverk3]

Progress on fuselage continues:

[wingsoverk3]

Many thanks to Erik (Ka-6BR), the ventral trapdoor which puzzled me "holds a drogue chute that attaches to the tail skid strut. There is a spring on it, and the latch is operated by a control cable from a servo as near as I can read from the plan."
Thanks Erik for the information. He adds: "the camouflage scheme... is inaccurate in most model kits and aircraft paintings.

"The DFS gliders that assaulted Fort Eben Emael and the three bridges in 1940 were light gray with side insignia painted out with a slightly darker gray.

"The swastika on the V-stab and crosses on the wings were not added until late in the war, as a glider was not considered an aircraft until then. I have found nothing on the squadron code letters & number codes on the fuselage sides.

"The late war 'C' model has the two doors on the fuselage left side and the MG-34 machine gun on the top. I don't know when the machine gun on the cockpit right side was first used. The pilot operated it by pulling a lanyard.

[wingsoverk3]

First avionics suite installed is RFD900 (900 MHz) telemetry radio modem. Since it's a two aircrew plane, might as well have clean uncluttered FPV video feed and let back-seater worry about flight and navigation data.
Glazed cockpit allows for two cameras, forward and rear-facing or a single one with limited pan and tilt. Plus, another camera embedded in wing all controlled via three-way switcher.
Nose will have HobbyKing Glider Nose Tow-Line Release mechanism and airframe will have flight stabilizer, perhaps APM 2.5 or 3.0. In theory, it'll be a lazy man's FPV bird being aero-towed by the three-IC-powered tug for most of the flight.

[wingsoverk3]

Many thanks to Erik (KA-6BR) for providing me with juggernaut of documentation on the original DFS-230.

[wingsoverk3]

The DFS-230 started out as a simple 4-channel analog 72Mhz build to match the Tante Ju mothership but when you put a bunch or retired EEs, well, you know what happens. Now it'll be open 433Mhz UHF openLRS (7-watt Tx) for RC which I've had good experience with. HobbyKing has come out with Orange version which I'm still waiting for. 1.5watt Mondo Extreme 5.8Ghz video downlink for FPV cameras, two in cockpit, one in wing, via 3-way video switcher. Flight stabilization is HK Orange or their APM2.5 clone. Then there's the 900Mhz telemetry for navigation and flight data, including temperature, pressure, airspeed sensors. I'm looking into coding the radio modem to include lost/downed aircraft locator beacon mode activated by magnetic switch. HK navigation strobe lights.
So much electronics: I hope I have enough energy storage onboard as I drew the line on solar panels on wing.
Kanchenjunga is to be our San Grasso/Eben Emael. Longest towline I've used is 150-feet. Will experiment with 100-meters after maiden so I always get higher FPV that tow tug.
It's monsoon here so no flying or even paragliding. Lots of time on my hands.
Only problem I foresee is that I am working off of Klaus Nietzer's plans which has undercambered wings as with the original. The Hawkins plans appear more simple build with flat-bottom (I think Cark Y) airfoils.
Started work on empennage. Both H- and V- stabilators have CF spar caps to avoid chance of flutter due to short tail moment.

[wingsoverk3]

Very good question. My previous 1.55-meter sailplane builds vary between 300 and 450 grams. This one will be heavier. Weights thus far:

The battery is the biggest concern and I'll only know the smallest one I can carry after flight tests. I may just have to forgo live FPV and just record video and rely on telemetry from DFS-230 and FPV live video feed from Ju-52.
The extra servo will be programmed to release take-off wheel dolly and then the towline. I am looking around for a lighter continuous rotation winch servo. The B1226 I have is far too heavy, over 100 grams. I'd like to be able to adjust length of towline inflight. Have used nichrome hot-wire cutter for nylon towline release before. It works.

This build won't be entering any F3B, F3J, F3F, etc., events. It won't even be a conventional glider. Like the original, she'll be towed for the major part of the flight regime. For maiden and testing flights (hi-start or off slope), it'll only be the RC gear with small battery. I'll add the rest of the equipment in stages as I get more used to flying her. Once I get sink/glide rate polars, I'll know best airspeed for distance in the final Kanchenjunga configuration.

If I achieve a fraction of the polars of the original DFS-230, I'll be okay to get released on return leg as winds in October-November are typically west to east by south east so I expect good tailwind. As quoted at fpvlab, "My math says 1:1 glide back home......even a library book could make that glide ratio."

WRT leading edges of the V- and H- stabilators, they're triangle stock sandwiched to 3x3mm square stock. The spars are 3x3mm square stock capped by 3x0.5mm CF. Had to reinforce both for protection against flutter and for mounting GSM patch antenna in H-stab and 900 Mhz VP diversity antenna in V-stab. (The horizontal polarized 900 Mhz antenna goes in port wing). I deviated from Klaus Nietzer's plans for a number of reasons. His design does not have spoilers. I just received Hawkins version which I think is more suited to my 1.64-meter WS.

[wingsoverk3]