Composite Gliders

[JYZoom]

Got maiden done....quite happy with the outcome.
Can't judge the performance and I am adjusting from a 3M to 2M now...and also this morning cross winds making it hard.

I still do have CG issue with the redliner motor, still head heavy even with tail servo mounted on vtail.
Now I have decide if I used bigger lipos making it heavier...or I use smaller motor.
But I love the climbs with the redliner....pulling max of 700Watts with 3S, 8000 rpm and max 70A.

Jonathan

[tansc]

Can post pictures of e servo installation on e luna?

[JYZoom]

Servos on vtail closed up

Bro...think you sms me also....
Here is a closed up....I need to find a better looking servo cover, so far what I found and used here is a car refresher refill cover.



Jonathan

[Ghostfit]

WHAT THE !..... the servo covers !

There goes all the aerodynamics sleekness out the window !

[JYZoom]

WHAT THE !..... the servo covers !

There goes all the aerodynamics sleekness out the window !

Bro....you are right....this was the problem I was chasing that the glider nose dive once I slow the speed down. Now with a simple change....everything fly super nice now.
What a glider to have.....thermal well enough ( can't compete with my Erwin....not many can )....and speed and acro well.

I think it is one good purchase. If you put a lot of detail work in building..it will come out even better then what I have.



regards,
Jonathan

[Twyl]

Yikes, did the instructions say to install the v-tail servos in the actual v-tail surfaces as well or is that just an original mod? Unless you are so pressed for room, I can't imagine the weight savings, if any, for counter balancing the motor would be enough to counter the drag introduced with that setup.

Sounds like it flys ok, but if that was how it was intended to be built I'm baffled.

-Jonathan x2

[JYZoom]

Jonathan X 2,

The RIOT is after all not those well designed and carefully build from Europe or US and expensive gliders. However it seems like it will does the job for me as a trainer so I can keep my Erwin and incoming European model safe from the "ground".

The idea of putting the servos in tail were pick up researching on this post .. http://www.rcgroups.com/forums/showt...+glider&page=5
The RIOT have a tendency of head heavy. Here is a comparison to Mini Graphite...and it is clear the ratio shows why. I did also cut out about 10mm the head so it feel to me better balance or counter balance.

[Hawkeye]

Why Choose 10mm thick mks 6100 when there are 9mm D60s or Hyperions DS09 or 8.5mm mks 65k???

[JYZoom]

Why Choose 10mm thick mks 6100 when there are 9mm D60s or Hyperions DS09 or 8.5mm mks 65k???

Hawkeye, absolutely right.
That is what I am thinking now. Got these servos before the Glider come in...

Jonathan

[Ghostfit]

I think what Bro Twyl means is that the V tail feather's servos could be located inside the fuselage instead of sticking out in the airstream.

Pictures of the rear end of that fuselage just begs for internal servos linked to cf tubes pushrods and ending in 2mm piano wire horns.
Something along the lines of this Strega setup: http://www.rcgroups.com/forums/showp...7&postcount=52

Brgds

[JYZoom]

I think what Bro Twyl means is that the V tail feather's servos could be located inside the fuselage instead of sticking out in the airstream.

Pictures of the rear end of that fuselage just begs for internal servos linked to cf tubes pushrods and ending in 2mm piano wire horns.
Something along the lines of this Strega setup: http://www.rcgroups.com/forums/showp...7&postcount=52

Brgds

Ghostfit,

I understand what Jonathan is saying.....i didn;t some research before I start the build. This thread shows how it suppose to be done as recommendation...http://www.rcgroups.com/forums/showp...9&postcount=33 however the thread also highlight that it is still nose heavy after that and actually the owner never got to fly and he also comment if he had know , he would put the servo on the tail. similar to Mini-graphite.

So it was good that I did it in the beginning...as I still have a bit of nose heavy...as I am using a big motor with redliner now.

Again...keep the advice coming....so far it seems to fly quite well.

Jonathan

[Hawkeye]

Servos in the tail are meant for balancing E converted gliders. Especially those with the joiner going thru the fuselage. If you plan to use a heavy motor,you are left with limited options to balance the plane.

1. Add tail weight
2. Move batteries as far back to the joiner.

When all that fails......shrink your motor or battery or put the servos in the tail or shorten your nose, or fatten the fuselage so that the battery can fit under the joiner.

The pros we have with control rods from the mid fuse to the tail is that
1. You get a lighter tail moment that makes the glider more agile
The cons is that your RX pack cannot be placed behind the wing as it gets in the way of the push rods

So the design considerations for pure slope gliders is somewhat different for motorised gliders. As an eg:, for pure slopers, RX, RX batts and larger servos are mounted up front so that you can balance the plane and provide a very light tail for the agile nature of sloping. Remember if you need more throw to get your tail where you need it to be, you are creating more drag. For sloping, its not preferable, for a motorised glider, you care less about that.

The issues is manufacturers cut short the design process and try to turn slope planes into electrics by leveraging the slope designs with limited consideration for placement of motor, esc, battery to balance the whole plane properly. So you are left with a compromised design somewhat. Neither here nor there.

[Hawkeye]

oh one more thing.....2M birds and 3m birds are differnt animals when it comes to balancing the plane as the longer tail does not allow you to put servos in the tail to balance the plane, it becomes too tail heavy.

You need to use servos behind the wing instead of servos in the tail as most 3M birds tail are longer. for 2M birds, servos in the tail are prefered due to the shorter tail.

[Twyl]

Hi Jonathan, I'm very sorry I'm not trying to thread crap as I really like your energy and I love to watch and learn how other people build. Hopefully, my posts are just promoting the learning and are not taken as a harsh criticism.

I guess the question begging to be answered here is, is the intent of the "ship" to be a fast powerful plane or a motor assisted glider? Hawkeye, made some very good points about manufactures cutting corners and so electrifying the Luna, maintaining the CoG and keeping it light may very well be a difficult challenge. Assuming the intent is to be a motor assisted glider, I do think the priorities might have been a bit confused as it seems like a glider is being attached to fly a motor instead of a motor being attached to fly a glider.

Regarding the build thread on RCG I don't think the guy was contemplating stuffing the servos into the tail surfaces but into the fuse of the tail. This would actually be a very cool way to try and mod it if you could get servos to fit, and keeping them inline would be a way to reduce drag as much as possible in the event they do protrude some.

I am not sure where I found this pic now, but I think it was a larger model. If this could be done it would free up the fuse for battery movement and add a little weight at the tail too, those f5b ships off course only have the one servo in the tail so no prob there.

-Jonathan x2

[James Lee]

Heh heh.... Hope I don't step on too many toes with this reply...

Agree with Hawkeye that servos in the tail is mainly for motorized gliders. But the slope glider definition is a bit narrow. Actually most pure gliders - slope ships, thermal duration sh?ps, scale ships, DLGs etc etc are set up with tail servos up front. That's usually the best way to get the lightest glider setup. Usually only motorized gliders have them in the tail.

The thing about flying gliders in Singapore is that we only have one slope with a short season and very very few people do tow plane/F3J/winch/high start launches. Motorized gliders appear to be the norm when Bedok is not flyable.

TWYL,
The priority I observe here for motorized gliders is not "have the lightest motor assisted glider set up", but "have a motor set up that can take a glider very strongly to altitud". Which is really impressive. This is how the hobby appears to be enjoyed here mostly. Only a few guys high start or winch...