Weight Notes, Thanks to Johnnie

Johnnie:

I did the following and have been mining the combined Affordaplane sights and seeing what CAN be done. Check this out and some that know might respond.

Affordaplane Materials Cost & Weights;
Per Aircraft Spruce & Specialty pdf catalog and internet search.

Bolts:
Actually priced the AN3 & 4 bolts. Then multiplied that amount by 2.5 (to simulate bolt, washer and nut combo), that came to $257.50. By adding each bolts lengths, a total rod length was determined, so a (kind of) bolt weight could be derived. That total was doubled to allow for a (kind of combo weight) bolt length plus the bolt head and nut. This came out to nearly 8 pounds. This doesn't include cable, cable tangs, hinges, rivets, or gussets and things.

Next was the tubing: size & weight per ft TTL WT TTL COST
46 ft of Sq tube. 2"X2".125 1.120 51.52 lbs 211.60
48 ft of rnd tube ½"X.058 0.0962 4.62 lbs 204.70
10 ft 1"X.035 0.1275 1.28 19.90
3 ft 5/16"X.049 0.0423 0.1269 6.75
132 ft 1"X.058 0.2060 27.19 382.80
64 ft 1 1/8"X.058 0.2321 14.85 185.60
24 ft 1 ½"X.058 0.3137 7.53 126.00
24 ft 2"X.058 0.4225 10.14 141.60
6 ft 1 3/8"X.058 0.2865 1.72 29.82
6 ft 1 7/8"X.058 0.3954 2.37 39.00
4 ft Al Rod 1" 1.2 4.8 46.12
14 ft 7/8"X.058 0.1777 2.5 35.00
3 ft Al Angle 2"X2" 0.125 1.5 4.50
------------------------------------------------+-------------+------------
130.15 lbs 1433.39
Above hardware 8.0 257.50
+-------------+------------
138.15 lbs 1690.89


We haven't gotten to the motor or re-drive / gearbox … so let's take a glimmer. Engine Choices (excerpt from plans) The Affordaplane was originally designed with a Rotax 277. With the weight of the test pilot being 240 pounds, and carrying a ballistic, it was not enough power. I recommend an engine with at least 35 horsepower, and weighing not over 80 pounds. You can choose from a rotax 377, 447, 1/2 vw (watch the weight and hp on these) a 2SI 35 hp, or a Kawasaki 440. The plans show an engine mount for the Rotax 447.

Rotax 447 engine specifications.
DESCRIPTION: Two-cycle, two-cylinder engine, oil in fuel lubrication
BORE: 67.5 mm (2.657 in.)
STROKE: 61 mm (2.40 in.)
DISPLACEMENT: 436.5 cc (26.635 cu. in.)
COMPRESSION RATIO: Theoretical 9.6, effective 6.3
POWER OUTPUT: 29.5 kw (40 HP) at 6000 rpm
TORQUE MAX.: 44.0 NM (32.5 ft. lbs.) at 6000 rpm
MAXIMUM RPM: 7000 RPM
DIRECTION OF ROTATION: Counter-clockwise, viewed towards PTO
CYLINDER: 2 light alloy cylinders w/ cast iron sleeves
PISTON: Aluminum cast piston with 2 rings
PISTON/CYLINDER CLEARANCE: 0.08- 0.09mm (.00315-.00354 in.)
IGNITION SYSTEM: Breakerless Ducati capacitor discharge ignition with magneto
generator.
GENERATOR OUTPUT: AC 12V 110W + 30W
RECTIFIER-REGULATOR: (optional) a.) #9103 requires minimum load 12 W (1 amp.)
b.) #9251 requires no minimum load
IGNITION TIMING: 2.09 mm = .086" BTDC
CONTACT POINT GAP: 0.4 mm = .015"
SPARK PLUG: 12mm NGK B8ES
ELECTRODE GAP: .015" GAP
CARBURETOR: 1 X BING 36mm, with hand lever choke
FUEL PUMP: pneumatic fuel pump #6903
FUEL: Regular gasoline, octane not below 90 unleaded
LUBRICATION OF ENGINE: Super two stroke oil (AV-2)
MIXING RATIO: 50 TO 1 (2%)
STARTER: Rewind starter
optional: electric mag side without recoil option
REDUCTION GEARBOX "B": Reduction gear-box with Torsional shock absorber
RATIOS: 2.00 to 1, 2.238 to 1, 2.58 to 1
DIRECTION OF PROP ROTATION: Clockwise, viewed toward prop flange
COOLING: Air cooled by axial fan
WEIGHTS: Engine without carburetor, intake silencer, fuel pump, Exhaust System......................
Carb With Rubber Socket.......... 2.0 lbs.......( 0.9 kg.)
Exhaust System (approx.)........ 10.8 lbs.......( 4.9 kg.)
Electric Start Kit (Optional).... 7.70 lbs......( 3.5 kg.)
Reduction Box "B" - Dry...........9.9 lbs.......( 4.5 kg.)



You still need gusset material, wheels for your landing gear, the plastic ends to mount your wing ribs to the spars (or foam to make the ribs). You'll need various wire rope cableing for your guys, rivets, seat material… etc, you'll just have to get the plans and READ them. One fellow told me a completed wing weighed 39 lbs (but he had a aluminum fuel tank in each.

You can lighten it up in several areas by leaving out the false spars, ribs, and nose ribs. No, it won't be quite as smooth looking but it would be functional. I too, will be doing further research to find ways to lighten her up and would appreciate any suggestions be emailed to me.

This is just something, I spent today putting together, as "FOR YOUR INFO" as a set of condensed ball park figuires. THANKS John

Tim W's Affordaplane.

Hey everyone, this morning I visited Tim W at the airfield. The weather concerned me on the way out. It was a little windy, a bit hazy, and the clouds were quite low. When I got to the airfield, he took me on a tour of his plane, and the build decisions he made.

Welcome to my first impression of the airfield... :-) Poor plane.

My first impression of Tim's plane however, was very good, and it stayed that way. His modification list is quite extensive. The winds were a bit high, so Tim kept his flying to a couple of quick runs down the runway.

Performance wise, with his MZ201 powered Affordaplane, is a mixed bag. The planes level maximum airspeed is in the 65mph range. However the climb performance is disappointing.

Hi Tims plane.

So, what all did tim do? He tried to make the plane easily disassembled. He did something similar to Gent's tail, where the horizontal stablizer can fold. ... except the control horns interfere with the rudder. On the bright side, having a hinge means you can use the pins as a quick removal tool. The main and TE spar are also held on with pins.

The tail originally just had single bracing wires, but Tim saw the leading edge dancing during flight, and he decided they needed some more bracing. While we're on the subject of flying surfaces, he also sealed the elevator and alerion gaps.

I really liked the landing gear. It's fiberglass rod, and beyond providing some shock absorption they are lighter than the per plans landing gear. They also fail progressively on a hard landing. (Tim's turning out to be a good test pilot.) Due to the way they are attached, they are easily replaced.

While we're looking at Tim's planes legs, I'll note that he did not use the solid aluminum round bar to transfer strut load from one side of the plane to the other. He used some flat 2024 plate. You can also see he doubled up the bottom tube. The stock gear were hard enough on the frame to bend it.

The MZ201 he's running is the planes second engine. It was originally on a Kawasaki with a reduction drive. His engine mount is 2" longer than per plans. Despite that, he has 20oz of lead on the tailskid.

I like the prop.

He also ran all cables for the control surfaces. I'm not sure I'd make the same choice, but I have the whole r/c plane thing going for me. But look at those beautiful belcranks. The cables also facilitated the folding tail.

Thank you Tim for letting me look at, and show off your plane.

Getting the plans.

I ordered my plans from www.affordaplane.com.

They were delivered within minutes via e-mail. You have 48 hours to download the plans, and only three attempts. So... make sure your internet is working, and plan on where you're going to save the files.

Sure the going rate for the plans is $8 a set, but having to spend that money again to get another copy because your hard drive crashed is going to make you cranky.