E-Flite Blade CP

The Blade is ready to run once the flight pack is charged and eight AA batteries are loaded into the transmitter. The stock battery is good for roughly six minutes of sport-flying.

 

Thanks to the latest distribution efforts (including those on eBay), the fixed-pitch, electric-powered helicopter market has been booming with remarkably low-priced RTF models. I’ve been fortunate enough to play with a number of these, and the experience has been challenging and rewarding. 

         

I’ve spent hours practice-hovering such helicopters. Without going into detail about how I know, let me tell you they are well engineered for durability. I also found out that the lack of ability to adjust the blades’ pitch angle became an unwelcome handicap when trying to maneuver the helicopters in flight.

           

The short story is that a helicopter acquires most of its stability by means of the spinning blades. The faster they spin, the more stable and maneuverable the helicopter is.

           

Fixed-pitch models work well in a hover since they need a relatively high head speed to stay aloft. Predictably, push them into forward flight and the lift generated from the oncoming airflow causes the models to climb.

           

To maintain a desired altitude while flying forward, the throttle has to be reduced. This, in turn, decreases the head speed, therefore decreasing stability. This flying peculiarity is uncomfortable to say the least.

           

Forward flight with a helicopter is best performed with one that has the ability to adjust the blades’ pitch angle. This is called Collective Pitch mixing. The advantage is that stability can be maintained even while lift is gained because the pitch angle of the rotating blades can be reduced, thus reducing lift while the head speed is kept at a comfortable speed.

           

I call the E-flite Blade CP (Collective Pitch) from Horizon Hobby a 300-class micro electric helicopter. The number is in reference to the Speed 370 motor used for main rotor power.

 

The E-Flite Blade CP meets all the aircraft requirements of the Academy of Model Aeronautics’ (AMA) Park Pilot Program. The aircraft weighs less than 2 pounds (the Program’s upper weight limit) and has a level top speed under 60 mph (the Program’s upper speed limit). For complete Park Pilot aircraft details, follow this link.

The AMA Park Pilot Program offers non-AMA members the opportunity to become AMA members at a much reduced cost. Park Pilot membership includes a great magazine “Park Pilot”, $500,000 personal liability insurance, $2.5 million liability insurance for the outdoor flying field or indoor flying site owner (see insurance details) and membership in the world’s largest sport aviation association – the AMA. For complete information and details about Park Pilot membership, just click here.

           

This model is an RTF package, meaning you take it out of the box and go fly. Hold onto the box because it’s excellent for storage and transport. To fly it the first time, all the pilot has to provide is a bit of helicopter experience and eight AA batteries for the transmitter.

           

What do I mean by “a bit of helicopter experience”? Even though the Blade package’s price spells “try me,” it is not intended for the first-time helicopter pilot. That is not without good reason; the control response is sensitive.

           

For the new helicopter pilot, a softer control feel is typically more comfortable. So for the pilot with some experience flying helicopters, the Blade is a great deal of fun because of its maneuverability.

Three microservos are used to support 120° CCPM mechanics. Note simplistic engineering and assembly. Wound antenna around gear posed no range issues.

 

           

The other thing is that helicopters of this size are a challenge to fly in the wind. The Blade is a delight to fly indoors, but the typical living room isn’t the practical place because of its size. If you’re thinking about making the Blade CP your first helicopter, consider yourself warned.

    

 My advice for you new pilots is to get as much computer-simulator time in as possible beforehand. In addition, buy a Training Gear Set (E-Flite item EFLH1128) that is made specifically for this model.

Sharp Blade: Now that I’ve gotten the “disclaimers” out of the way, I can write about all the fun I’ve been having with the Blade CP.

           

I took the helicopter out of the box and flew it first thing, as the instructions suggested. In less than a minute the eight-cell NiMH 650 mAh battery was fully drained and I recharged it with the included wall unit.

           

This charger is quick but it isn’t peak detect, so you have to keep an eye on it for the 90- to 120-minute charge time. When the battery gets warm, it’s finished charging.

           

In that first hop the Blade seemed fairly well trimmed, so I’m guessing it was factory test-flown before it was packed (as the ads claim). After that little session I took advantage of the downtime to go over everything.

           

With the Blade you get a complete model helicopter with three servos, a gyro, an ESC, a receiver, and a transmitter. Three E-flite microservos (item EFLH1030) are securely arranged at the 120° points around the swashplate to suit the Cyclic/Collective Pitch Mixing (CCPM) mechanics. The advantage of this system is that the parts count is low; therefore, the overall weight is reduced while increasing mechanical advantage.

           

The trick is that all these servos need to be mixed for the system to work properly. Lucky for us, the included transmitter has all that done and is complete with Idle-Up mixing that makes it possible to fly the Blade inverted. I’ll get into that later.

           

 Almost the only thing missing on the transmitter is a Throttle Hold feature. Also, the detents in the throttle stick are coarse, which makes it difficult to make smooth throttle changes. There is a trainer switch and buddy-cord jack, so theoretically a dual-transmitter training system could be set up.

       

On the helicopter end there’s a little black box inside the plastic canopy where all the wires from the motors and servos go. E-flite calls this the 4-in-1 mixer. It’s a compact unit that contains the receiver, ESC, mixer for the tail rotor, and piezo gyro.

           

The Blade is available in six different frequencies on the 72 MHz band. The receiver uses the negative shift deviation, and it’s FM which means it will work with other transmitters.

 

Tail-rotor control is via N30 motor geared to large single-piece rotor. Counterclockwise rotor’s speed is increased to turn nose to the right and decreased to turn left.

 

           

 The speed control will handle as much as roughly 8 amps but does not feature a voltage cutoff of any type. The mixer and the gyro can be adjusted through the side of the 4-in-1 with a small screwdriver.

           

This helicopter is as simple as it gets. The frame is essentially a mix of fiber-reinforced plastic, carbon-fiber rod, and tubing held together with cyanoacrylate glue and fuel tubing.

           

Before you start shaking your head, understand that for light weight and durability this machine has got it all worked out. On top of all that, very little maintenance is required.

         

I’ve had enough mishaps while practice-flying the Blade to understand that it will hold up exceptionally well. And although it doesn’t have the bells and whistles of a multidollar 3-D machine, this helicopter is maneuverable and can be flown smoothly.

         

The included flight pack is good for roughly five to eight minutes of flying. I’ve gotten longer flights when I’ve slow-charged the pack on a variable-rate charger and used it right after the charge cycle was finished.

           

There was a little “wag” to the tail, which I guess I didn’t notice during the first flight and attributed to a gyro gain setting that was too high. The 4-in-1 electronic unit can be adjusted for gain and mixing (P-mix for all you helicopter people). I backed the gain screw out approximately 10° and the tail settled down.

           

 From then on it was a matter of getting used to the Blade’s feel. The first thing that took a little getting used to was the lag in pitch response when advancing the collective pitch (that’s the throttle to all you airplane people) for liftoff into a hover. I would notice that at half stick the head speed would be going like gangbusters, but the helicopter wasn’t coming off.

           

Moving one click at a time, when 60% stick travel was reached the machine leaped from the ground. To keep it from hitting the ceiling, I throttled back, then up, then down, bouncing the Blade in the air until I found a happy place in the collective stick.

 

 
E-flite 4-in-1 control unit houses all electronic frequency and mixing components. An LED next to adjustment controls

     

The service team at Horizon Hobby put together a troubleshooting guide online, and it suggests that this lag is caused by the mechanics in the head sticking. Several options are offered to solve the problem, including taking the head apart and fine-tuning the parts clearances.

     

The first thing I did was closely examine the servo response to collective pitch movement. All the servos were doing their job, but the mechanics weren’t transferring the commands because of slop in the ball link at the lower paddle control pushrod.

       

 It turns out that the ball ends on the upper swashplate were undersized. To make them larger I coated them with thin cyanoacrylate glue; three coats enlarged the ball enough to improve the linkage fit. After that the collective pitch movement instantly transferred to the head and the Blade could be smoothly lifted off the ground.

           

As far as small helicopters go, the Blade is a pleasure to fly. Control-stick movement is a tad sensitive. If I were using a computer radio, all I would have to do would be to program exponential into the steering controls so it would suit my flying style.

 

            The mixer does a good job of managing the torque created by the moving blades. Extreme collective changes, such as when doing a fast climbout from a hover, cause the helicopter to swing to the left. Adjusting the mixer control can adjust the compensation to the pilot’s liking.

           

The flat-bottom blades that come with the helicopter generate extra lift, which is good for hovering practice. If you plan to do a great deal of hovering practice, an ideal upgrade would be to use a two-cell Li-Poly battery pack and change the motor to the type with an 11-tooth pinion (item EFLH1110D).

           

 While you’re at the hobby shop pick up the E-flite Aerobatic Enhancement Kit (item EFLH1168). This will be handy for when you want more performance, but, more important, the package includes heat sinks for the main and tail motors. Installing the heat sinks will dramatically improve the life of the motors by removing the damage source of the internal brushes.

 

E-flite Blade enhancement kit contains aerobatic wood blades, heat sinks, and new Speed 370 motor with smaller pinion to make the system suitable for three-cell Li-Poly power.

       

A two-cell, 1200 mAh Li-Poly battery is inexpensive and will double the flight time the stock NiMH battery provides. By changing the gear ratio the performance stays roughly the same for hovering and sport-flying. As I mentioned earlier, the ESC doesn’t have a voltage cutoff. Protect the Li-Poly batteries by landing at the first sign of motor power loss.

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