Multiplex EasyStar

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Multiplex Easy Star

The Easy Star (sometimes abbreviated EZ*) is a great plane for learning to fly. It's very stable and will right itself if you let go of the sticks. It's large enough to cope with 10-15mph of wind and can survive a tremendous amount of abuse without breaking. A nose-first or cartwheel landing usually causes no damage because the motor is mounted behind the wing and the foam is Multiplex’s durable Elapor foam (similar to EPP). If the durable Elapor foam does happen to break, it usually will break cleanly, meaning you can easily glue it back together using regular, non foam safe CA (more commonly known as Super Glue).

The large size means that it needs a couple of football fields of space to fly comfortably, especially as the standard speed 400 motor can only manage a gentle climb. However, that does not mean it is limited. The Stock setup can push the EasyStar to around 50-55mph in level flight while just cruising around, and can do loops from a gentle dive. The glider style design means that it is very efficient, with a very shallow glide slope compared to most trainers. It's quite possible to slope or thermal soar the EasyStar, although it's no match for sleeker composite gliders. It will slow down to a crawl but can pick up a lot of speed in a dive and loop fairly easily.

The EasyStar is available Ready-To-fly or as a kit. The kit is very easy to build and fairly tolerant of COG position - anywhere on the spar cap will be fine, and up to an inch outside it is manageable for an experienced pilot.

These user-friendly characteristics make the EasyStar a very popular camera platform for Aerial Photography or FPV


Specifications

  • Wingspan: 54 in
  • Length: 36 in
  • Wing Area:
  • Weight: 24 oz

Motors

In-runners or canned out-runners are a quick replacement for the stock Speed 400 brushed motor. Bare out-runners will require more creativity to mount. A common method is to glue a plywood firewall over the hole where the brushed motor would fit. Prop size is limited by the motor position - the standard prop is 5.5", but a 6" prop will just fit. Larger props require the motor to be mounted higher, which often looks ugly.

  • A 2408-21 kv1750 'Bell' motor, with a 8x6 prop and 3s lipo battery is cheap and sufficient for a 45 degree climb and aerobatics but needs to be mounted quite high to fit such a large prop.
  • Mega 16/15/4 & APCE 6x4 prop makes a good upgrade.
  • Himax 2825 2700kv & APCE 5.5x4.3

Batteries

The EasyStar will fly on a 7 cell NiCd pack, but 8 cells is significantly better. The original pack was only 6 cells, and was rather underpowered.

Eight AA cells weigh about 200g and need to be right at the front of the nose to balance, but they are slightly too long to fit either across the fuselage or vertically in the nose.

Eight sub-C cells weigh about 500g (which is a lot for this plane) and need to go somewhere under the leading edge, which is possible if you remove some foam. Seven cells won't fit without mods either.

Six sub-C cells will fit in the cockpit and balance, but at this voltage and weight the motor doesn't really provide enough power to climb.

The ideal pack is somewhere between AA (too light) and Sub-C (too heavy), with a capacity of 1-2Ah

A 3 cell, 2000 mAh Lipo battery weighs about 200g, but is easy to slide right to the front for balance. This is a lovely light, powerful option, but the stock motor won't last long if you use full throttle, and it's very easy to over-discharge the LiPo because the EasyStar will fly even when the battery voltage is very low. You can limit this by timing your flights, but battery usage is highly variable so you have to be very conservative. An ESC with a LiPo aware LVC is necessary to get the most from these batteries.

A 2 cell 2Ah LiPo is too light to balance the EasyStar, although there's plenty of room for two packs, which works nicely. A 2 cell 3Ah Lipo should be about the right weight, and a slightly larger prop could be fitted to increase the power (a 6x3" prop will just fit if you use a collet adapter to move it back slightly).

The Mods!

In rough order of popularity:

Larger rudder

The most common mod is to increase the size of the rudder, because when gliding (at low speed with no prop wash) the rudder is not very powerful. Typically the fin is cut vertically above the rudder hinge, adding about 30% to the rudder area, or the rudder is extended backwards with thin foam or plastic - or the rudder is replaced entirely.

Brushless motor

The stock motor lasts long enough for most people to progress onto their second plane, but then they decide that a more powerful EasyStar would be fun too. Some in-runners will replace the speed 400 exactly, but out-runners need to be mounted outside the nacelle. Typically a plywood circle is glued over the hole and the outrunner screwed to the plywood with a firewall mount. It's also possible (but not as neat) to use a stick mount glued to the top of the nacelle.

With a 3 cell lipo, and a good brushless motor, you can expect very powerful climbs, and setup right, the plane will go vertically after launching. Some setups will cruise at around 1/4 throttle, but push to full throttle (sometimes abbreviated WOT for Wide Open Throttle) and the plane will takeoff vertically like a rocket.

Mega 16/15/4 & APCE 6x4 prop makes a good upgrade, if you want to use the standard motor mount.

Here's an easy way to mount an outrunner slightly higher than stock, so a 7" prop can be used (which is more efficient when used at higher power than the stock motor).

EasyStarPlyMount.jpg EasyStarPlyMountPlan.jpg

LiPo batteries

LiPo batteries should be avoided while you are still crashing frequently but once your flight times are limited by your batteries and not your flying ability, LiPos can give you 20 minute flights. The stock setup uses a 7.2v NiMH pack, which means a 2 cell lipo pack will be a drop in replacement, and give slightly more power (although less power than a 7 or 8 cell nicad pack). Also, on top of slightly more power, the flight times can double using a 2100 mah pack.

The Easy Star will balance using a 2100 mah 3 cell pack at the front of the cockpit, or a 2 cell 3000mAh.

Ailerons

Ailerons can be added to improve control in gusty conditions, usually with one servo in each wing, at the end of the spar. The wires can be run inside the spar caps. Some modelers like to mix in rudder coupling to aid in turns, and make them look cleaner, but it is not necessary to. Beginners mostly won't notice much of a difference.

Canopy

The canopy clips don't last long, and most people find an alternative method of securing the canopy (magnets, velcro, rubber bands or hinges and clips).

The sides of the cockpit are weak spots that often bend or crack in crashes, you could strengthen this area by cutting off the bottom inch of the canopy sides and gluing them to the fuselage sides, then using an alternative canopy retainer.

Aerial Photography

The EasyStar is a great model for taking photos remotely. It's easy to wedge a camera in the cockpit (with no prop to spoil the view) and the docile handling gives clear pictures, even if there's some wind.

Canon P&S Camera Mounted in an Easystar

Lights for night flying

The predictable handling and ability to survive a poor landing make the EasyStar a good choice for night flying.

Links