Need a design/plan for a scratch built plane suited for FPV.

What is the best shape for the wing? An ideal span? Should the wing have high dihedral, be polyhedral or straight?

Can it be built around a 2mtr glider wing?

@ashok baijal
Aah, no response all day...

Why do you need plans?
Just tell me your payload, and i'll build it for you!
Especially as i now have balsa, depron, hardwood spars, CF tubes, CF fabric, glass, epoxy etc.
Also stabilisation, telemetry, GPS etc

(Before others jump on me, clarification that Ashok is an old personal friend)

@Iyer. There are so many persons into fpv on the forum but no one is prepared to share his build? Or do I take that all use readymade planes? Anyway was hoping of starting a thread were discussion on suitable plans for fpv  planes could happen.

I made one and it flew excellent. copy of MQ1 raven from US army. search the internet, i lost my plan with my old mobile dead.
or i will send the dimensions. made from 8mm EPS foam and hot glue. 3 channel with tip dihedral.

Ashok.P

Shape of wing is dictated by the style of FPV you want to do.

If you are into a more pleasurable soaring eagle kind of flying who is interested in just the plain view and docile flying among clouds then a polyhedral wing or dihedral wing is more suited for you. Further it gives you self leveling characteristics which is more of an insurance for you for those few seconds of occasional blackouts in FPV view in mid flight which happens some times.

Long Span Short chord, thin wing profile and aerofoils also adds up to the good glide characteristics. if you are into the above kind of flying.

However if you are a more advanced FPV pilot and an Adrenaline Junkie, who is more interested in flying through trees and valleys with tight turns around corners and up and down following the terrain of the area and more interested in speed and aerobatics associated with it and for the rush of it then a flat wing with short span is ideal for you. Best configurations are flying wings, combat wings, You may even consider the forward swept wing like a Spector which is extremely well suited for such kind of flying.

How ever you need to have a good setup which gives you minimum disturbance in video and a clean video.

Spector



Wing span wing span is dictated by the total payload you want to carry. It can be anything from as less as 50 cms up
as dictated by the payload you want to carry.

This is an amazing custom build FPV model of wing span 60 cms by AleG from Bangkok.
http://www.rcindia.org/rc-general-topics/flying-fpv-in-india/
http://www.rcgroups.com/forums/showthread.php?t=1156779
http://www.rcgroups.com/forums/showpost.php?p=14503727&postcount=36

I was after seeing few of the videos of AleG I was really motivated for FPV. Some amazing clips in the above threads always a pleasure to watch.



But sky is the limit for the the ingenuity or creativity as far as FPV or far that matter RC building is concerned.

To answer your question short, yes a 2 mtr glider wing is perfect to build an FPV model around it.

@sundaram sir,
What about something like Parambir sir's Ronin (if memory serves me)?

Iyer sir Ronin was a huge model with 2.6 Mtrs wing span which is suitable only if you are planing to carry say like 20000mah 3S or a 10000mah 6S Lipo and multiple cameras and gimbal mounted camera for very long haul.  To begin with a mtr wing span is ideal to carry most common FPV electronics with 3000mah 3S lipo for a good 20 Min flight and around a 1 Kg AUW.

Plans for AleG model are here

http://www.rcgroups.com/forums/showatt.php?attachmentid=3298487&d=1276310665

http://www.rcgroups.com/forums/showatt.php?attachmentid=3300432&d=1276401413

Ashok Sir,
perhaps you could try something like the FT Versa Wing with a blunt nose conversion or maybe the FT Kraken (which may be too big for your needs).

Sir there are many fpv scratch builds, it would all depend on your style!! One of my friends got a skysirfer with landing gear and with a good motor and 5000mah battery clocked around 38 mins flight time using all fpv gear!! Very cheap and effective setup!!

Regards
JK

Thanks for bringing life to the thread. I agree that so many different styles are possible for fpv and in the long run will have to have more than one.

Planning to start with a slow soaring type of plane. I have an Orange Box glider which has a 2 mtr wing which I think can serve the needs of my first fpv. I have a question. The wing is polyhederal (dimensions given in the image below). Since I plan to use an APM as the autopilot, is it necessary to have ailerons,and if so, should I modify the wing to dihederal shape before adding the ailerons?

sir as far as i know you surely need ailerons for effective fpv, and i dont know about the second part!!

regards,
JK

No need to break the polyhedral joints.
Remove about 1/4" from present TE, so that you have about 1/4 thickness.
Add 1&1/4" TE stock to inboard panels.
Hinge similar stock to outboard panels as ailerons.
Being outboard, despite being half span, should give at least 3/4 the rolling power as full span strip ailerons.
Other issues:
Power pod?
Motor in nose?
Estimated all up weight and wing loading?
CF tape reinforcement along top and bottom of spar?

APM can be easily configured to fly only a rudder and elevator model or only a 'V' tail model with polyhedral wing. So you can very well use the wing without making any modification.

That said it will always be better to have a model with aileron if you can mange to add one like how Iyer Sir has suggested or by any other type of modification for aileron.