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Jul 19, 2012, 10:53 AM
Registered User
Need advice on design and build of a large scale model airplane;
Before I buy parts and build this model, I would like some of you, experienced individuals in design and build of such models, to verified my design calculations and recommend if this model will fly, or not, as designed. Most of all, I am not sure that 13 lb. weight of airplane (not including engine and fuel) is the correct weight for this size of a model.
Target Size:
Wing Span = 134” ; Chord = 22” ; Aspect Ratio = 6:1 ; Area = 2950 Sq. In.
All I have at this point is an Engine runs at 7200 RPM, 1.1 hp , torque of 0.811 ft. lb./sec.
I am presenting here the results of my design calculations (based on googled formulas and web sites calculators):
Cruising Speed = 55 mph
Propeller Size = 20 x 8
Total Airplane Weight = 20lb (engine + fuel = 7 lb.) that leaves 13 lb. for the construction materials, controls, battery etc.)
Wing Loading = 15.62 oz./sq. ft.
Thrust-To-Weight = 1.17
Cl = 0.128
Lift = 19.3 lb (used rho=1.18 kg/m cubed) – not sure why this number resulted in less than 20lb). The 20 lb number given above was used in calculating Wing Loading and Thrust-To-Weight). Should I use the 19.3 lb number instead or what should I use for my final total weight target?
I can provide the formulas/calculators I used for all the numbers, if needed. Just wanted to save text space.
Thanks from David
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Jul 20, 2012, 01:02 AM
Registered User
Who could better quality scan this drawing?
Bazz Bomb published Aeromodeller October 1964.

Thanks in advance!
Nov 05, 2012, 04:28 PM
Registered User
hogal's Avatar
Quote:
Originally Posted by urfin
Who could better quality scan this drawing?
Bazz Bomb published Aeromodeller October 1964.

Thanks in advance!
Try this for size. I have cleaned up the scan ready for completing a CAD tracing but this .pdf should get you onto the building board

Al
Nov 09, 2012, 07:56 AM
AND FOR MY NEXT TRICK....!
jodini's Avatar
I've bought 3 short kits from Bob Holman and he does TOP NOTCH work! The plans are clear and the parts are well done. I've heard negative opinions on other short kits providers, but never been disappointed with Bob.
Here are the three:
Carl Goldberg Sailplane
Gyrace Autogyro
Record Hound
Jan 06, 2016, 04:25 PM
from new zealand
hi first time on here Im from New Zealand. I'm hoping that someone might be able to help me with an old plan Im looking for its a modelair juggler
Sep 17, 2016, 06:14 PM
Registered User
yes i have the modelair juggler plan
Sep 18, 2016, 02:17 PM
Thermals, Tom
RyanNX211's Avatar
Quote:
Originally Posted by jodini
I've bought 3 short kits from Bob Holman and he does TOP NOTCH work! The plans are clear and the parts are well done. I've heard negative opinions on other short kits providers, but never been disappointed with Bob.
Here are the three:
Carl Goldberg Sailplane
Gyrace Autogyro
Record Hound
Didn't know Bob did an autogyro. What does he use for rotor blades?
Sep 18, 2016, 02:22 PM
Thermals, Tom
RyanNX211's Avatar
Quote:
Originally Posted by Leadchucker
Got into a peeing match with a guy in here over the same thing. I told him the plane he had built was an enlarged Quaker Flash not a Flying Quaker and he gave me about 16 rations of crap over the whole thing. I was just being nice in case he had ideas for competeing with his plane ( it really was a blown up Quaker Flash)

Be very careful of all plans, I ignored my own advice a bit and look at the difference. The old tail was from a set of plans from 1970, the new one from a recent "redrawn" set.
I assume he built the Ben Buckle Quaker. That's a suble difference that few will catch.
With Playboys, it should be more conspicuous but when I showed up with a Junior 54 scAled to 900sq" and a 1/2a Texaco Senior, there was no shortage of people snickering that I mislabeled them.

Is that a Miss Deleware tail? We posted our dieselised one to YouTube


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