Dave Lacey’s E-36 #4 (at left). The stab is mylar covered. The wing and fuse are covered with Japanese tissue. The nose area is reinforced with fiberglass. Back of the E-36 timer (above center), the ESC plugs into the Berg connector marked M, the servo into the one marked S. You can get one from BMJR. Stone Age’s E-36 timer is 1.5 inches by 0.9 inch and weighs less than 5 grams. It mounts by four #0 or #1 screws in the corners. It’s so simple to use a caveman could use it (above right).
The C2404 motor from HobbyKing is called a Lotus RC C2404 by the manufac-
turer, and has a 1,900 Kv, is about 21 grams, and is made for 2S Li-Pos. This same motor is also sold by outfits in the US, (like In- nov8tive Design, and RC DUDE) as the 2404 T-Motor. A 7– 5 APC e-prop loads the motor very well—pulling about 50 watts input. The recommended GWS 8–4 works, but seems less efficient than the APC. GWS slow flyer props flex too much, and turn faster than the recommended max rpm. An APC or Windsor Air Screw is a better bet. Of course, a folder would be even better. Unfortunately, the motor comes with a prop saver and some machining is required
to fit a folder. A HobbyKing 12A BlueSeries ESC weighs 10 grams and will do the job nicely. Since we are only running the motor for 15 seconds or less, you don’t have to wor- ry about air cooling the ESC, it can be buried in the model. The E-36 timer weighs 5 grams. The prop weighs about 7 grams. The all-up power system weight comes to about 70 grams with a switch. Throw in another 5 grams for a small DT servo. Typical E-36 models have been coming in at 140 to 180 grams. Now what model do you want to put it in?
Brian Malin
http://www.bmjrmodels.com has two, the KIWI-E-36 and Sparks. He will also be selling the E-36 timer. Don De-
E-36 Rules
15.1 Model Requirements 1. 36-inch maximum projected wingspan allowed. 2. 120-gram minimum weight, ready-to-fly, required. 3. No autosurfaces allowed.
15.2 Power Requirements 1. Any type electric motor allowed. 2. Nickel or lithium batteries allowed, 2-cell lithium limit or 6-cell nickel limit. 3. Gearing and folding props allowed.
15.3 Flight Requirements 1. Two minute maxes required for all flights
2. First three official flights to be made with a 15-second motor run each. If all max- es, a fourth flight to be made with 10-second motor run, and if maxed, then all later flights to be made with 5-second motor runs until a max is dropped.
3. Six attempts for the first three official flights is allowed, immediate declaration re- quired and 20-second maximum for attempts, overruns being automatic attempts for the first three official flights and overruns after the third official flight to be au- tomatically awarded a “0” score.
loach
ddeloach@comcast.net has the Super Pearl 202-E based on the Mini-Pearl. The November–December issue of the NFFS Digest features Hal Cover’s Short Circuit with 220 square inches of area and a weight of 180 grams. Full sized plans are avail- able. Some of these models were designed for heavier motors and batteries, thus the nose might need to be lengthened to get the c.g. right. In the case of Sparks, which I have, sim-
ply gluing a firewall/motor/mount to the front former does the job. This model was originally set up for a GWS motor on a stick mount. Needless to say this power won’t hack it under the new rules. I’m going to re- fit mine with a Cobra C-2204/40 brushless
motor, with a Kv of 1570 rpm/Volt from
http://www.rcdude.com. This is a little heav- ier, at 22.5 grams, than the motor Don likes or the T1804 from
http://www.innov8tive
designs.com that Dave Lacey uses, but it has a 3mm shaft that my folder will fit on without any machining. It is four to five times more powerful than
the stick motor it is replacing and requires down and left thrust to compensate for it. I’m guessing 5 degrees down and 3 left. Some test flights will sort this out. The radial mount makes changing thrust offset much easier than with the old stick mount. I will use my usual approach of using a radio receiver in lieu of a timer for the initial test flights. A much safer procedure! I think a folding prop is well worth the extra weight in maximizing flight times. Be advised: the motor runs and two-
minute maxes prescribed in the E-36 rules are seen as appropriate for large field com- petition. CDs are encouraged to modify the motor runs and maxes to suit local condi- tions. This is a NFFS event and records won’t be kept, so fly smart and keep your models on the field.
The BMJR KIWI-E-36 is based on the KIWI-Coupe wing and tail with a redesigned fuselage for motor, timer, and battery (above left). It has a 36-inch span with 168 square inches of area. Flying weight of the prototype is 154 grams. Sparks is a Rex Hinson design with a 36-inch span with a 175 square
FLYING MODELS
inch area (above center). Designed for the old rules using Ni-Cds and brushed
motors, it is easily adapted to the new rules. The T1804 Kv 2250 rpm/Volt motor that Dave Lacey uses on E-36 #4 (above right). Note the integral prop saver which makes it difficult to fit a folder.
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