Topic: Aircraft gross dimensions(span, weight etc) for AdruAutoPilot

Hi!
I am doing an academic project testing various 'open-source' AutoPilot systems like AdruMega, UBD4 etc most of which have the same physical dimensions and weight. For this, I need to make an electric Fixed Wing 'traditional' aircraft that can carry 100 gm dead weight for a minimum of 10 minutes flight in the air.

I need to test the aircraft without the autopilot first and then replace the dead weight with the Autopilot board later once I am confident. So what I need is   

• Aircraft Dimensions: Estimate of Span(I guess around 70 cm ?), Gross weight including payload weight of 100 gm(my estimate around 600 gm)
• The electronic Set-up: Battery parameters (11.1 volts, mAmpH ??), or suggest me a battery  , Brushless Motor parameters, ESC - 30 amp should do

Thanks in advance,

Bharat

Essentially most of the stock "sports" aircraft in the 300-500w class could meet this mission requirement. Are you looking for an off-the-shelf airframe or do you want to design something special? I suspect your design driver won't be weight - it's more likely to be the internal volume required to accomodate your control system.

In the off-the-shelf area something like a multiplex fun-cub or twinstar, or the wot4 (probably in the wooden form to give you the internal equipment volume). The choice of airframe will then drive your choice of power system (motor/battery/ESC), but a typical 400-500w power system to allow 10 mins of cruising flight might be a motor in the Axi 2820/10 class, with a 40-50A capable ESC (ie a 40A Jeti/hacker/kontronic ESC or a 60A "cheapie") and a 3-cell battery of 3000-4000mAh. But it depends on the aeroplane, the required take-off performance and the performance required in the "cruise" phase of the flight.

£0.02 supplied,

PDR

I'm not entirely sure what your intention is here?

1 Are you building a free flight model which will be controlled by an autopilot in due course?
2 Are you building a radio controlled aircraft which will be flown with an autopilot in due course?
3 What do you mean by "autopilot? 
3a Do you mean a device which maintains a fixed course/altitude and heading without human intervention?
3b Do you mean a device which will pilot the aircraft around a pre-planned flight path without human intervention?
3c Do you mean a device which is pre-programmed prior to take off?
3d Do you mean a device which does either a or b but which can be set in flight rather than pre-programmed on the ground?
3e Do you intend to have a radio controlled safety back up at all times?

The more information you supply, the more likely you are to get relevant help.

Good luck!

Are you looking for an off-the-shelf airframe or do you want to design something special?

I am looking for design plans which I can use to build the aircraft myself. And if the pdf plans are unavailable, I'd at least like to have an idea of the basic parameters of the aircraft like AR, span, gross weight and the corresponding power system that would be required to meet the mission requirements. The volume that the boards isn't much, but I guess in addition to the space used by battery, ESC and servos, it'll be significant constraint. I looked up multiplex Fun Cub - and it seems it'd work for me but I already have the motor and stuff, I wonder if I could cut out the foam body myself  , and not have to spend another 100 USD for the kit

@meharibear: Autopilot is something that would be an interface between my reciever and the control servos, motor etc. It'll have an IMU, GPS etc and sense its attitude and position, process the it through its flight control software(check out DIY Drones) and give inputs to the servos. Essentially, it'll support waypoint navigation, where in I'll manually take-off, and then switch to 'AutoPilot mode', then the Auto Pilot will maneuver the aircraft through the (predefined) flight course, and the manually i'll get the aircraft to land. Auto Pilot could help me just stabilize the inputs I give through the Tx or take over the whole control. I'd be using it for the later.

Thanks.     


Ps. With real aircrafts, Initial sizing is a peice of cake since well documented historical data is readily available and one can fit curves from range and endurance requirements to get these parameters, like in the book by Raymer.     

Which country are you from, I'm guessing not the UK as you quoted 100 USD. The reason I ask is this sort of project in the UK would have to be very carefully done to ensure it is not illegal. It's not an area I have any real knowledge of apart from knowing the CAA are very strict on this sort of thing. I think this is where the earlier questions were coming from 

@sizzling: I am from India(Mumbai), that won't be a concern, I guess my Proff. would have taken care of that before giving me the project 

Ok, I just weighed my fuselage and it weighs 400 gms, the Wing has a span of 1 meter, area of 2300 cm^2 and weighs 250 gms, add a dead-weight (later to be the payload) of 100 gms. So by my estimate the model weighs 750 grams without the battery, motor and ESC. What kind of power system would be good if I just want to loiter around for at least 10 minutes at a stretch ?

@sizzling: I am from India(Mumbai), that won't be a concern, I guess my Proff. would have taken care of that before giving me the project 

Ok, I just weighed my fuselage and it weighs 400 gms, the Wing has a span of 1 meter, area of 2300 cm^2 and weighs 250 gms, add a dead-weight (later to be the payload) of 100 gms. So by my estimate the model weighs 750 grams without the battery, motor and ESC. What kind of power system would be good if I just want to loiter around for at least 10 minutes at a stretch ?

Hi there - NEVER assume Anything - Especially when it comes to your Proff!  He might well be waiting for you to check out the legal and airworthiness restrictions on your project and report back on any constraints they impose on your design - you are working at University level now, not High School!

As for your sizes,  they are "doable" but I would go for something much larger because, to put it simplistically big aircraft fly better!  This is a simple fact dictated by the recognition that the atmosphere the aircraft has to operate in is always "full scale"!  In addition, you will be much less weight and space critical.  I would be inclined to use around a 60 inch (1.5 metre) wingspan model.  If you have no modelling experience then brushless electric power using Lipo batteries may be simplest for you - this appears to be the route you have chosen.  However using a simple cheap Glow motor like an SC46 would mean that with a large fuel tank you can achieve long endurance and turn around time between flights can be very short.  This will allow you to conduct far more test flying on any one day.

I'm sure that the electric experts will be along in a minute with their suggestions for suitable motors, speed controllers and batteries