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-   -   New OXAI CITRIN by Wolfgang and Roland Matt (http://www.rcuniverse.com/forum/electric-pattern-aircraft-385/10874037-new-oxai-citrin-wolfgang-roland-matt.html)

cartercg 12-24-2011 01:20 AM

New OXAI CITRIN by Wolfgang and Roland Matt
 
Check out the new bipe by Wolfgang and Roland Matt:

http://www.oxai-rc.com/main/detail.aspx?ID=86

Has anybody taken delivery of what looks like a fantastic plane? What were the component weights and how do they compare with the claimed weight of 2350g? Making weight is going to require careful component selection.

How does it fly? Any flight reports? Any comparisons with the Peridot which is their latest mono design?

The specs suggest the use of BLS153 on Ail, S9071SB on Elev and S9070SB on Rudder.

The S9070SB is only 5.5kg at 6V which seems a little on the low side for Rudder? The S9071SB is not brushless and I doubt I’ll use the serial bus capability. As such I’m considering using BLS153 on both Ail and Elev (the BLS153 is the same size and weight as the S9071SB). And then using a BLS451 on rudder which is brushless, 10.6kg and .10sec at 6V. The BLS451 weighs 26g more than the S9071SB, but I expect the benefits of the brushless and more powerful servo warrant the additional weight? Any advice on servo selection would be appreciated.

Rest of my build would be Plett Advance motor, Spin99, Emcotec regulator switch, carbon spinner and prop, Futaba R6208SB receiver, TP4400 or TP5000 depending on weight.

Any opinion on the OXAI supplied linkages that come with the likes of the Peridot/Citrin? I’ve used the Central Hobbies carbon/titanium linkages in the past but will only do so if the linkages with the Citrin are not top notch. Any opinions on this?

Gulliver 12-24-2011 10:07 AM

RE: New OXAI CITRIN by Wolfgang and Roland Matt
 
what are thos little thingies on the wing tips for ? If they are side force generators, how come they have (lightening?) holes cut in them ?

apereira 12-25-2011 05:47 AM

RE: New OXAI CITRIN by Wolfgang and Roland Matt
 
The Citrin compares to the Amethyst, and Wolfgang told me he was very surprised, he didn't think anything would fly better than the Amethyst, but it does! he said , and that can only mean it is an extraordinary airplane.

If my Amethyst is 4900Gr with all the BLS servos, I'm sure the Citrin will make weight easily.

Regards

Alejandro P.

Chris Moon 12-25-2011 06:23 AM

RE: New OXAI CITRIN by Wolfgang and Roland Matt
 
Oxai is taking orders for the Citrin and is scheduled to begin shipping to customers in March.

Doug Cronkhite 12-25-2011 11:41 PM

RE: New OXAI CITRIN by Wolfgang and Roland Matt
 
Those SFGs make no sense at all. If there's one thing a biplane is never short of it's rudder authority.

flyboy91 12-26-2011 07:48 AM

RE: New OXAI CITRIN by Wolfgang and Roland Matt
 
I wonder if there not used for sfg's but rather tip planes to increase aileron authority similar to what seba has been doing on his planes? It would make the most logical sense to me. Like doug said, bipes do not need any help with rudder authority.

Andrew

cartercg 12-27-2011 02:27 AM

RE: New OXAI CITRIN by Wolfgang and Roland Matt
 
Perhaps they're not SFGs but rather the worlds most expensive wing tip protectors. :D.

TonyF 12-27-2011 06:01 AM

RE: New OXAI CITRIN by Wolfgang and Roland Matt
 
I never thought the tip SFG's did much for side force. But they do steady the roll axis especially in turbulence. I did the test too many times back to back with my PassPort. No significant increase in knife edge, but just less movement in turbulence. Why, I don't know. Maybe they help clean up the tip vortex a bit.

Doug Cronkhite 12-30-2011 09:53 AM

RE: New OXAI CITRIN by Wolfgang and Roland Matt
 
That makes some sense although I thought tip vortices didn't really manifest until aft of the surface itself. Certainly the aileron flow fence has some merit as well to help avoid airflow spill-off from the ends of the surface. I would think if that's the reasoning they would bookend the ailerons instead of just having fences on the outboard edge.

Angus Balfour 12-31-2011 03:14 AM

RE: New OXAI CITRIN by Wolfgang and Roland Matt
 
Wolfgang uses them for lateral stability in turbulent conditions :)

Bill Clark 01-01-2012 08:00 PM

RE: New OXAI CITRIN by Wolfgang and Roland Matt
 
that is probabley the the sexiest bipe I've ever seen

papaone 01-02-2012 10:32 AM

RE: New OXAI CITRIN by Wolfgang and Roland Matt
 
1 Attachment(s)
Hello

Others nice pics of Citrin
How is the motor fixed ?

http://blog.naver.com/PostThumbnailV...entCategoryNo=

Ryan Smith 01-02-2012 10:58 AM

RE: New OXAI CITRIN by Wolfgang and Roland Matt
 
Claude,

There appears to be a nose ring mount made of CFK. You can see the four motor mounting bolts visible in the picture, they are silver in color.

I must say, I love the nose of this airplane; it's a completely fresh approach to nose design and I think it looks really nice, and is very effective.

geoflys 01-08-2012 08:10 PM

RE: New OXAI CITRIN by Wolfgang and Roland Matt
 
1 Attachment(s)
We Liked the linkages supplied with the PERIDOT...with one reservation...the threads on the rods seem a little shallow....Will give them a try and keep a watch on them...I think they will be fine....The ball bearing linkages are fine for the horn side...but I nixed them on the servo side in favor of ball links. The PERIDOT is a FANTASTIC airplane. With a Q80,and carefull weight consideration on parts..we wound up at 4975grams...a bit dissapointing, however we cut weight everywhere EXCEPT for custom servo wires/leads. We used the lightest axles,wheels,spinner,prop, regulator, and rx,available, and were very carefull with glue.( TP 5000's.10s)

cartercg 01-09-2012 03:13 AM

RE: New OXAI CITRIN by Wolfgang and Roland Matt
 
thanks Geoflys. That's a pretty good weight for the Perridot. What struck me is how heavy the canopy is. A local here cut out the pilot and associated base it is mounted on and appears to have saved more than 40 grams. Something worth considering if you're not mad about having a pilot in the plane. Thanks for the feedback on the linkages. Hope the Perridot works well for you. It is most certainly an excellent plane.

Regards
Clint

geoflys 01-09-2012 10:54 PM

RE: New OXAI CITRIN by Wolfgang and Roland Matt
 
That was one of the first things that I thought about..., Im glad to hear it can be done....I was concerned that if the pilot and the base were removed that the canopy might lose its rigidity, and get "floppy".No one wants a floppy canopy!

cartercg 04-17-2012 11:23 AM

RE: New OXAI CITRIN by Wolfgang and Roland Matt
 
Hi, well my Citrin should be ready to ship from the Oxai factory tomorrow (18 April). It will probably take about a month to ship here, clear customes etc. I'm looking forward to putting her together and flying her. I understand that the bipe will take a bit of getting used to. Anyway we have our South African nationals at the end of April so I'm busy practicing for that anyway. Anyone taken delivery of a Citrin yet? Any flight reports/suggestions? I'll post weights and build pics when I get mine and put her together.

Regards
Clint

Spillmann 04-17-2012 09:46 PM

RE: New OXAI CITRIN by Wolfgang and Roland Matt
 
Hi Clint

I maidened my Citrin some days ago. Weight is 3800g without battery. (Hence it is lighter than my Peridot).

Equipment:

Hacker Q80-13S
Hacker/Spin 99 Pro Opto
Mejzlik 20x13 (new light version)
Marquet Spinner
6x Futaba BLS 153
1x Futaba BLS 551
PowerBox DigiSwitch 6.5V
Futaba 7008SB receiver
TP 900 mAH 2s1p RC battery

The plane flies fantastic and its rudder authority is perfect for the P13 schedule.

Rgds, Jean-Claude

cartercg 04-18-2012 10:07 AM

RE: New OXAI CITRIN by Wolfgang and Roland Matt
 
Hi Jean-Claude,

Thanks for the feedback. That's great, and a very good weight for a bipe. Making weight should be possible even with 5000mAh packs. My build will be very similar:

Pletti Advance
Spin99
Mejzlik 21x13
Marquet Spinner
6x Futaba BLS 153
1x Futaba BLS 451
Emcotech receiver switch/regulator 5.9V
Futaba R6208SB receiver
TP 720 mAH 2s1p RC battery

I expect my weight will be very similar to yours. I expect it will also be great for the F13, with all the KE elements.

What tendencies does she have. Do you need much rudder to aileron mix? Is your CG similar to that in the factor specs?

Regards
Clint

Spillmann 04-18-2012 10:47 AM

RE: New OXAI CITRIN by Wolfgang and Roland Matt
 
Clint,

I can't say too much about CG and mixing, as I could only do one flight so far (due to the bad weather here in Switzerland). The first impression is, that it needs only very little mixing and that the indicated CG is ok. I will let you know more as soon as I have the chance to make some additional flights.

Rgds,
Jean-Claude

grantb 04-18-2012 11:26 AM

RE: New OXAI CITRIN by Wolfgang and Roland Matt
 
Mine is shipping too :D:D:D

Clint forgot to mention that he gets to build the prototype and mine gets all the improvements:) Pity they won't be ready for the RSA NATS.

Any comments on the difference in handling between a normal pattern plane and a bipe???

Anything that one should look out for on takeoff, in flight, landing ?

serious power 04-18-2012 12:23 PM

RE: New OXAI CITRIN by Wolfgang and Roland Matt
 
Hi,
Yes; check that your not seeing double :D:D

Brian

Malcolm H 04-18-2012 11:49 PM

RE: New OXAI CITRIN by Wolfgang and Roland Matt
 
Go on Brian,

You know you want one!

Malcolm

Rombaut 05-02-2012 06:18 AM

RE: New OXAI CITRIN by Wolfgang and Roland Matt
 
What a plane!

Here a video of the premiere of my Citrin.

http://vimeo.com/41352274

It's amazing, did not believe there was a better plane than the Amethyst, W.Matt has done another time!

4850 grams with Dualsky Motor.

Regards!

Juan

Jetstream 05-02-2012 07:19 AM

RE: New OXAI CITRIN by Wolfgang and Roland Matt
 
Great video!!!


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