to determine whole weight of rc plane. (individual part wise)

Started by ashwini06, September 28, 2014, 04:32:32 PM

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ashwini06

I am using coroplast of 400 gram/m^2 or 0.04 gram/cm^2 density. I want to measure its whole weight to assign it a electric motor, prop, servos and batt. I have no direct approach. I have stuck in complicated calculations. please tell me some standard formulas according to a standard figure by which i can easily understand.
My plane's wing dimensions are 110*20 cm and it is in the flat bottom airfoil.
Please tell me some standard formula to determine it's whole weight along with a suitable figure.

ashwini06

I can not post plane's full scale designed diagram because present time i have it's rough scratch only. If any one need, he can say me for all the dimensions.
OK, i am going to post a similar plane's photo with approx dimensions. If it not useful, Please tell me.....

K K Iyer

@ashwini06
Data about trainer from Vortex-rc.
Specifications:
Fuselage length: 780 mm
Wingspan: 1450 mm
Wing-area: Trainer: 465 sq in.
Recommended All out Flying weight:
Trainer : ~650gms
Wing loading: Trainer: ~7 Oz/Sq. ft.

This should give you some parameters.

But if this is your first model, instead of building from scratch, perhaps you could try the Vortex-rc trainer kit, with its matching electronics pack. Or something like a Skysurfer or Trainstar from RCB.

Suggestion for success with first model:
1. Avoid reinventing the wheel
2. Try a proven model. Borrow if need be!

However, if you need to go your own way, some guidelines in the next post.





K K Iyer

2200sqcm wing top
2200sqcm wing bottom
1000sqcm stab
  500sqcm fin
Say 6000sqcm

Assume fuselage length 90cm, cross section 10x7.5cm.
So sheet reqd for fuselage 90x35cm, or say 3150sqcm.
Assume that only 70% will be used due to taper towards tail.
So say 2200sqcm

Total 8000-8500sqcm.
If your material is 0.04gms/sqcm, coro weight 320-340gms
1000mah 3s 80gms, motor 50gms, esc/prop/rx 40gms, servos 40gms, pushrods/ undercarriage etc 30gm

Total 550-600gms. Say about 7oz/sqft - nice for a trainer
Your picture shows 1500gms. Why?

No need to reinvent the wheel!
Ok?
Regards



ashwini06

thank you so much... i will follow exactly.... i was copied that picture... it is not mine...



regards


ashwini06

I have a 6*4 feet corrugated plastic sheet having 400 GSM density and it's thickness is 3mm (obviously it is rectangular). I want to find it's total mass. Kindly help me any one.

K K Iyer

@ashwini06,
THINK!
You have all the bits of information needed.
All you have do is to connect them to get the answer.
Try.

Then weigh it to verify your calculation!

ashwini06

yes, i have understand, but i want to know a specific way to know every thing, even you was also calculate all the data at beginning and then verified to them.
so i am also want to develop all theoretical knowledge. if u have any other approach to calculate these factors, please share with us.


regards

K K Iyer

@ashwini06
OK.
Your sheet size is 6ft x 4ft.
Or about 180cm x 120cm (taking 1ft=30cm)
So its area is 21600sqcm.
Or 2.16sqm.
Since the material is 400gms per sqm, the weight should be
400 x 2.16 = 864gms


ashwini06

yes, i did the same calculation after a long wrong calculations last night... ultimately i got the answer... answers are very close to your data... i am just satisfied....

thank you.... Mr. Iyer


regards