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Oxai Galactika unboxing, assembly, setup, maiden etc.

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Old 05-11-2018, 01:36 PM
  #176  
flywilly
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... and, if possible, park so you can assemble the airplane on the downwind (protected or 'lee' ) side of the car. Or as most of my fellow club members say: 'why fly when it is that windy?' - not pattern fliers! ;-)
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Old 05-11-2018, 03:28 PM
  #177  
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It would not be much flown here if I was not flying also when it is windy. I have nothing against flying in rather windy conditions, it is harder to fly and enhance Your flying skills.
It is just litte uncomfortable on the field in hard winds and landings is sometimes more demanding (and little more risky).
I have flown in a competition with winds that was around 12 meter per second and it was rather demanding both the flying and the landings.
I would not practice at such high winds for sure.
The top wing on Galactika is huge, about 30% of wing area (I have measured). It is the top wing, if it is mounted, that will throw the model around in the air if very high winds, if one place the model on the ground (without wing) without securing it to the ground. The top wing has a rather high angle of attack when model is sitting on the wheels on the ground and a strong wind gust can easily get enough force on underside of top wing to flip the model over on the side or upside down.
I usually have the top wing mounted at storage and transportation.

/Bo

Last edited by bem; 05-11-2018 at 03:40 PM.
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Old 05-13-2018, 02:24 AM
  #178  
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I was out flying yesterday. I had put up my small "signs", (that I have permission to put up) on the full scale airfield, for the limits of the F3A box limits on the ground (150-260-260 meter).
When I was ready to fly it was a person with a dog that slowly walked the whole line from sign to sign, stopped in the middle and did someting with the dog. Walked past the last sign, came back in a few minutes, walked back at the same line. After I had flown twice, the same person walked again with the dog same route and back. Well, the space is free for anyone to walk on but the airfield is huge but it just seemed this person had to walk twice exactly where I was flying. Anyway, at last walk I had the person in talking distance and wawed and the person came to me. I asked if the person was disturbed by the flight. Yes she said (she is a police officer to profession I found out), "it is disturbing with the whispering sound in the air" she said, while I was flying (my electric powered Galactika). She wanted to walk at the field with the dog in silcense she said. Remember this is a full scale airfield (and a model flying field). I said I can understand this and promised to fly more often on other side of the main runway to disturb the lady slightly less when she walked on the other side of the runway (who know when). Problem is that the sun is on that side for me so I have to use a sun shield then (I'm flying to the south then). The lady has moved in to a house (former airfield attendant house in 1950-1970th)just 200 meter from the the corner of the airfield (it is about 700 meters from our start/landing spot) and I asked if she could hear the plane inside the house when I was flying but she could not she said. Well, people have extraordinary requirements, considering this is actually an airfield. I personally do not think it is so smart idea to move into a house near an full scale airfield if one want dead silence in vicinity. Anyway we said goodby after some more talk and she seemed to understand we wanted to continue fly model aeroplanes on this airfield despite she had moved in to a nearby house. Our field is an ex. military war airfield used at WW2 until the propeller era ended and Jet planes took over in our Airforce. It has been free flight models flying here since 1950th and radio control since 1970 on this airfield. Modelflying on this airfield is threatened from various directions today: authorities (the airfield is also a Culture reserve, created to preserve this last almost complete war airfield in our country, as a museum), this sole nighbor I was talking about (that could potentially rase claim about our modelflying activity "disturb" her) and also the Aviation authorities that now have demands for authorization for airfields where modelflying take place if flying over 120 meter (in unrestricted airspace, like our field), and or with heavy models over 25 kg. Modelflying is really under hard pressure here, and especially this airfield I fly most. The Authorothies has even made an economic evalutation of the full scale club at the airfield so they, if they decide so (with our taxpayers money), can expropriate the land (runway including model flying field), hangars etc. If that will happen modelflying will probably be banned also if fullscale flying will be banned. It is really sad when it seems different activites can not coexists.
The full scale club has an electronic (and paper) petition going on and so far over 1200 signatures (electronic+paper) has been received, that support the club in their strugle to remain at this field.

https://translate.google.com/translate?sl=sv&tl=en&js=y&prev=_t&hl=sv&ie=UTF-8&u=http%3A%2F%2Fnamninsamling.se%2Findex.php%3Fsida %3D2%26nid%3D11462&edit-text=&act=url

It is rather ironic that even the former chief of Swedish Airforce Museum signed the petition, despite this is an ex Swedish Airforce war airfield. I guess he could see the unreasonable demands from the authorities to this small full scale flying club that strugle to survive.
We are two modelflying clubs that fly more or less regularly at this airfeld, and pay to the full scale club an annual fee (4000 SEK / $460) so we can use some of their land for pit area, winch area (F3B) etc.
We fly sport flying, F3A, F3B and F3C at the this field.

/Bo

Last edited by bem; 05-13-2018 at 03:11 AM.
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Old 05-17-2018, 12:39 AM
  #179  
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Hi,
I have been out flying after work this week and the weather has been wonderful.
Yesterday it was a guy with a powered paraglider at the field. At first it was no wind that made it difficult to get the needed lift on the paraglider wing at start. But later in the evening it started to be windy, but gusty. The guy decided to try one flight. He came up from the ground but shortly therefter while still flying low suddenly the paraglider was swept by a hard wind to the right and then came into tailwind and the paraglider wing lost lift and the guy hit the ground (not that hard) and was then dragged on the ground in the wind by the paraglider wing, first a short distance on the grass, then over a rather deep trench, then over a road with gravel, then over the next trench where he stopped. The guy got bruises on one arm, the jacket ripped up but otherwise he survived this incident fine. The paramotor got a bent protecting ring and a broken carbon propeller. It could have been much worse.
The guy sent an SMS to me today and said he was fine, and I'm glad he is. He said he learned a lesson to not fly when gusty winds like it was yesterday.

/Bo

Last edited by bem; 05-17-2018 at 12:54 AM.
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Old 05-30-2018, 06:13 PM
  #180  
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I've been following this thread, or should say I've been reading this thread and I now have a Oxai Galactika. I thought I would share a bit about my setup.
First off, I am running a V4 Contra drive, powered by a Pyro 600-94 10 pole motor, swinging Falcon 22x20 in the front and a 22x22 in the rear. This is powered by 2 Zippy 5000 mah, 25c flight packs, and a Jetti Spin Pro 99 ESC. I am running two 1100 mah LiFe RX packs with a "Batt Share" I have extended landing gear to allow for a better prop clearance and am running the "clipped wing" set like you would see with the Galactik. I have both sets of wings, but at this point I like the clipped set better. The landing has a bit more sink rate, and it seems to handle the windy conditions better. I originally installed the rudder servo in the tail but found I could not get the plane to balance. It is now located in front of the wing tube, along with the two RX batteries.
I have been flying a MythoS 125 for the past few months, and it is a great plane with no bad habits. I managed to win all of the events in my class (Intermediate) with it, against folks flying much more sophisticated equipment. This however is a revelation! I have only managed to put about 25 flights on it but it has been really easy to "trim" thanks to this thread, and some help from folks on another forum. It's not perfect, but it is damn close. I still have a slight pull to the canopy on a extended down line, and an ever so slight pull to the canopy on left rudder knife edge. Vertical is arrow straight and the plane feels very secure in any attitude. I love the MythoS, but the Galactika is just that much better.
Currently this is what my settings are:
Weight 4985
CG 217 mm
Stabilizer 0.0
Wings +0.6
T-Can 0.0
Motor Right thrust 0.0
Down thrust .4
I thought I would share what I have so far....
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Old 06-07-2018, 11:16 PM
  #181  
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Hi,
Mooney78865, great to see Your progress and settings with Your Galactika. It is nice to have such info as Yours gathered in this Galactika thread, in case someone else search for info on this plane. It is not that much info on Galactika on internet when one search. I suppose Galactika is not so common among F3A flyers, probably mostly because of the high cost of this ARF plane.

For me I'm trucking along with my Galactika this season and it will probably be in use next season also (it will be the 4th season with my Galactika then).
Next in the activity list here is our national Championship in class FAI F3A and F3A-Nordic (Advanced Schedule is used in Nordic class).
I will be Contest Director so it will be rather much work from now to the contest (July 7-8). We will have an international Contest at the same time, "Borderline Cup (Granscupen in Swedish) where usually many Norwegian pilots participate. It is an old Contest that started in 1974 (but then at another place). It is a challenge with two Contests (same flights count for both Contests) in two classes at the same time. But the scoring application "MultiRes" we use up here in our Nordic countries makes it managable (we had same dual Contest in 2016 also so I know it works). With good preparations and help from our local club it will hopefully be a great Contest.

/Bo

Last edited by bem; 06-08-2018 at 05:06 AM.
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Old 10-15-2018, 11:37 AM
  #182  
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Hi Bem,
Saw your adaption to the Galactika for a pull pull setup.
Recently maidened my Galactika+
It is 3900 without battery, so with the new Hacker5100 at 1100gr its flying weight is 5000gr.
Would like to know from you if the the more centerd position of the rudder servo had a noticable positive effect on flying behaviour ?
Regards, Hans
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Old 10-15-2018, 10:55 PM
  #183  
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Hi Hans,
The main reason for me to move the rudder servo to front was to be able to use lighter flight battery to get the total weight down.
The weight saving resulted in slghtly better performance, better vertical capabilites.
The Hacker Eco-X 4600 mAh F3A Editon has been enough to fly the P-19 schedule (if it is enough to fly the F-19 I do not know).
It is hard to tell if just moving the rudder servo from tail to front has given any noticable advantage but at least in theory it is better to gather as much weight as possible close to Center of Gravity point. At least I have not found any negative effect but I can not say I have notied any positive effect to be honest. I know of one top flyer (Lassi Nurila from Finland) that also use pull-pull for elevators, and that I have not seen on F3A plane before. I saw his Sensation biplane in 2017 both fly and on the ground (close for inspection). I do not think it was for weight in tail he choose the pull-pull solution also for elevators (he had it for rudder as well).

Hans, may I ask about the Galactika+? (no hurry for answer)
1) How is it with the top wing (canalizer) has it control surface along whole trailing edge as can be seen on many photos on Galactika+ or is it only about half of the trailing edge that is "break" (as seen on CPLR Galactika+)?
Is the break configured so as when throttle is at zero (break on position for ESC) the Control surface on top wing goes up (45 degrees or how much?)?
Can You post some photos of this arrangement with the top wing and it's break control surface?
2) Could You take a photo of the fins under the belly of fuselage and post? And tell how long a fin is at fuselage surface and also how tall it is and if possible the angle between the two fins?
I have some thought I might buy a new top wing with the break and also cut the wing tips on my Galactika (non plus) to get same wingspan as Galactika +. I may also add the belly fins. The sligfhtly changed rudder on Galactika+ I would not bother with on my plane.
3) Can You list all changes (if You know) in a Galactika+ compared to the Galactika?
It would be interesting to know how long is the wing carbon tube for example (since it was problem on Galactika with to short wing tube).

What motor, ESC and prop do You use?

It is slight negative that Hui Yang F3A as it seems has not been able to keep the weight down on Galactika+. It seems to be as heavy as Galactika (made by Oxai). Personally it would have been interesting to test a Galactika or Galactika+ with flight weight of 4500-4600 gram. It should make it fly crispier probably. Sometimes my Galactika, that now weight 4880 gram (with the 4600 mAh battery), feels still a little heavy in the air in some manouvres.

/Bo

Last edited by bem; 10-15-2018 at 11:02 PM.
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Old 10-16-2018, 12:49 AM
  #184  
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Hi Bo,
Some quick info.
Motor OS belt
Controller Kontronik Jive 80HV
Prop Rasa 21*16 Mag6 in three blade configuration (So actually 20,5 * 15 because three hub is a bit smaller)
Servos's Futaba 173 on elevator 174 on aileron 171 on rudder 153 on brake,

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Old 10-16-2018, 12:53 AM
  #185  
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20*5 cm

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Old 10-16-2018, 12:55 AM
  #186  
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80 degrees angle

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Old 10-16-2018, 01:03 AM
  #187  
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From factory the angles were when stab is seen as 0
+0,9 for aileron
-0,7 for canalizer
Still had to add substantial up elevator in flight.
After half roll had to 'catch' model to find level flight again.

Therefore removed the silicone tabs and thinned the seating material at the rear.
This changed the canalizer angle to about zero and improved rolling behaviour.

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Old 10-16-2018, 01:06 AM
  #188  
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Center of Gravity. Suggestion from Factory = 210mm.
That is just a bit in front of middle of tube.
Found that way to be foreward, had to use lots of up or down in level flight.
I ended op at about 225mm, just in front of rear side of the tube.

Wingtube is 595mm

Last edited by Hans Meij; 10-16-2018 at 01:08 AM.
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Old 10-16-2018, 01:16 AM
  #189  
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Folding prop.



Cooling controller. Helped a lot. From 60 to 30 degrees

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Old 10-16-2018, 06:07 AM
  #190  
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Hi again Hans,
Interesting photos and info You posted. Thanks.
Folding props that You have on Your motor is little unusual.

How much weight is Your top wing includung servo and linkage shown in the foto?
How many degrees is the throw on your top wing break surface?
Is it actiaved at zero throttle with full throw or is it a gradual defelection on the break surface as throttle is moved near zero to zero?

regards,
Bo

Last edited by bem; 10-16-2018 at 06:14 AM.
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Old 10-16-2018, 06:50 AM
  #191  
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Hi Bo,

It is 230 gram complete and has abouth 55 degrees of max deflection.
With a point mixer on last three clicks on throttle.

However I did not have it active yet. The Galactika is the most 'slippery' F3a model I have flown.
On half power it is fast and wants to fly fast and big.
The braking of the prop seems to be enough when flying fast and big.

Regards,
Hans
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Old 10-16-2018, 09:52 AM
  #192  
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Hi,
You are not alone to think Galactika is a fast/slippery plane. I struggled with my plane on downlines until I figured out I had not set enough hard break in ESC. I have written about it in this thread:
Mezon ESC: high brake power % setting - OK?
Now I feel much more comfortable in downlines with my Galactika.
I would not mind more break effect from a top wing like the one on Galactika +.
Galactika is a very precise plane, but sine it tend to be rather fast it leave not much room for corrections, many times one fels slightly "behind" and almsot a need to catch up. My previous plane, Sebart MythoS Pro, was more forgiving avd slower in general but still precise. For a good pilot that has good flow in the flying most of the time Galactika/Galactika+ should be a very good plane.
It is OK for me but I probably would do slightly better with a slower plane.

Thanks for the info about top wing weight and approx deflection of break surface.
/Bo
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Old 05-04-2019, 04:53 PM
  #193  
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Hi,
Snow and ice is gone now where I live so I took out my Galactika last week for some flights. First day all was fine, nice weather and no problem with plane although I felt rusty flying the P-19 schedule. Om Friday it was not so nice, weather was lousy and plane got one damge.
When I arrived at the airfield it started to snow (or maybe small soft hail) but it lasted only for about 30 min (I had the model under a tarpaulin then).
Then I flew 6 flights. When I unmounted the wings and was about to stuff them in the wing bags I noticed on underside of left wing a 100 mm crack in the balsa over the area where the wingtube is located in the wing. I'm sure it happened during flight because I inspect the for any damage before I mount them on the fuselage every time (and when finished flying for the day).

So I had to to cut out a "hatch" (90 x 50 mm) outside the damaged area and inspect. When I opened the hatch I had cut out I could not see any damage in the structure where the wing carbon tube is located. I inserted the carbon wing tube in wing and bended hard in all directions but I could not see anything strange. A slight flex vertically was possible to see, but it is no chance a wing can break (I put considerable force in the bending test). The wing tube inside the wing has in the ends ribs in plywood that the tube go through.
I decided to strengthen the "box" I was able to see around the wing tube with some glass+thin epoxy, It was little awkward to get the glass and epoxy inside this box but eventually it was finished. After it was dry and all seems to be OK and I glued back the hatch with epoxy.
I will do the same "operation" with the right wing. There is a tiny crack on top side of right wing but it has been there for a long time so I do not expect that crack will be larger but I will do same strengtening of this right wing also.
I suppose it is the snap rolls that is the root cause to the cracks in my wings. It is my 4th season now with my Galactika EP.
I know "Hui Yang Professional F3A" has longer wing tubes in Galactika these days but when I bought mine (it was made by Oxai then) it had the shorter wing tubes.

I will try to find some decal slightly larger then 90 x 50 mm to put over the "hatch" area.

/Bo

May 3, short snowfall…




Ready to fly with my Galactika EP...




Crack (about 100 mm) underside left wing...




"Hatch" 90x50 mm ready to be cut out with a scalpel...




The crack...




Reinforcement with 25 gram glass and epoxy inside the "box"...




Hatch glued back with slow curing epoxy...


Last edited by bem; 05-04-2019 at 05:56 PM.
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Old 05-11-2019, 02:48 PM
  #194  
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Hi,
Little more "trouble" today.
At the airfield (full scale runway with grass) someone had left a 250 mm (10 inch) long and 50 mm (2 inch) wide piece of hard wood on the runway. On second start from runway I hit that piece of wood at take off with my plane. The piece flew about 2 meter up in the air and I first thought the rudder fell of, so I made a quick landing. No damage on plane really but the tail wheel nylon bolt that the tail gear pin go through was knocked off. A small dent underside stab also. I inspected the wood piece and it has bite marks on it so it must have been a dog that dropped it on the runway i think. Although the airfield is inside a large wolf territory I do not think it was a wolf that dropped it. I see people walk on the airfield with dogs (most of them do not use dog leach despite it is not permitted to have dogs loose on the airfield). I used some tape to hold the tail gear wire (that normally goes through the nylon screw) in place and I flew about 10 flights without any problem at start and landing. I will from now on inspect the part of the runway we use for modelflying, take off and landings, if anyting is laying on the runway. Such piece of hard wood should be a danger to full scale planes also I think, risk for prop strike os similar.
So I have now just replaced the tail gear nylon pin (screw) that was knocked off. To drill out a nylon screw is not easy… I had ro carve with a modelknife around the 4 mm old nylon bolt and then pull it out of the balsa in the rudder. Mounted a new 5 mm nylon pin (screw) instead that should be little more durable.
There is more, what's the proverb.... an accident seldom comes alone. I cracked the display also today on my Futaba 14MZ, I just pressed as usual on the screen and it just exploded in a sunburst pattern. It is still possible to view everything on the screen but I can not press anyhing in lower right corner on the screen. I have to use the "wheel" in lower middle part of screen window now to navigate and select on screen. I guess I have to replace the display now (I know it is not cheap).
That is all for today folks.
I plan to fly tomorrow also and hope all will work more normal and not too much "unexpected" things happen.
/Bo

The piece of wood that was on the runway that I hit at a take off...




Tailwheel removed and new 5 mm nylon screw mounted and glued with epoxy mixed with microfiber so it was more thick...




Tail gear mounted back again....




Cracked screen on Futaba 14MZ...


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Old 05-14-2019, 11:27 PM
  #195  
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Hi,
Have been flying two more days, each day about 10 flights, and not a single problem with plane, radio or anything else.
I have experimented some more with the ESC break settings and increased from 84% to 90% break strength (in my Mezon ESC) and it slow down the plane slightly more in downlines. I'm little surprised that such high break strength setting is needed, but in this Galactika plane that is very slippery it is needed. My Futaba T14MZ has been sent to our Futaba service guy in our country, hopefully I will get it back next week. I have another T14MZ as loan to use now.

Every Tuesday it is fly-in with barbeque at the local full scale club at the airfield and this time it was a plane from Aeroclub in Gothenburg that visited, a 240 km round trip (about 1:15 hour flying time), it was a Piper PA-28-161 Cadet (very similar to a Cherokee). That hotdog he was eating was 2:30 hour total flight time and US$330 rent of plane worth. But it was a nice fly-in with barbeque so I'm sure he had a nice evening.
The full scale club members was flying their planes, for example one Pitts S1S (from 1976) and and old Aeronca 7AC (from 1945 but in very good condition). The local full scale club's own plane, a Piper PA-28-140 Cherokee (from 1968), was not flying this evening but it had just got a brand new radio installed (for $2700). Other planes in the full scale club is Yak-52 (from 1980), Giles G-202 (from 2002) and Lancair-235 (from 1990).

/Bo

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Old 05-15-2019, 11:10 PM
  #196  
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Hi,
I changed in my Galactika the rudder servo, Futaba BLS171SV, a while ago since it had developed little too much play in the servo gear. Replaced it with a spare BLS171SV I have. I will change the gear on the old BLS171SV so I have a spare servo just in case.
The plane tracks little better in yaw axis now.

I have also changed the CG on my Galactika, I moved the LiPo flight battery about 10 mm more to the front (the battery weight is about 990 gram). The plane is more stable in all all axes but is slightly more sluggish on the control surfaces input from the sticks. I have also to press sligftly more down elevator inverted but that is a minor and easy adaptation. The snap roll is little easier to perform and the plane keep direction better after a snap. The plane is less sensitive to side winds also. When plus and minus is compared the plus outweight the minus by far in my opinion.

My LiPo safety box hinge on one side broke yesterday, after 7 years of use. I have a spare same safety box, but if that will break it is no spare to buy since it was sold by Robbe in Germany and they are no longer in business. The box was named "Robbe LiPo Tresor". This is how it looks like in below video. I use it to store my 5 LiPo packs that I use while flying. The box has nice rounded corners and is easy to have with You while travel in car etc, but is rather heavy.
/Bo


Last edited by bem; 05-15-2019 at 11:12 PM.
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Old 05-16-2019, 02:02 AM
  #197  
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Hi Bo,
Moving 1Kg (990g) forward by 10 mm in a 5Kg model moves the CG 2mm forward - a small change really !!?

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Old 05-16-2019, 05:55 AM
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Hi Brian,
It is a small change but it has a noticeable effect in my case. I have tried to have the LiPo battery even more to the front, maybe another 10-15 mm or so but it felt to noseheavy then and did not perform some manouvres in P-19 so good, and it got too slow in control surface response for my taste, it felt I not had the model guite in my hands when flying then. I really tried back and forth between with old CG and the new CG (with the battery 10 mm more to the front) but decided in the end the flight characteristics was better overall with with the battery slightly more to the front. I suppose different planes are more or less sensitive to small changes of CG, my Galactika seems rather sensitive. My old plane Sebart MythoS Pro was not as sensitive.

/Bo

Last edited by bem; 05-16-2019 at 06:14 AM.
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