Tag Archives: cx3

Blade CX3 nearly meets it’s demise – out of action

Yesterday evening, was a great evening to fly. Not much wind, very very light rain and nobody at the ‘fly zone’ to accidentally kill. When you are unleashing an 8 year old piloting a P-51 Mustang model, these are things you need to consider. To be honest, he’s better at flying it than I am.

While the P-51 was zooming around the park, sometimes slamming into the ground nose first at full throttle (foamy planes are really good trainers) I took up the two Helis for some practice.

First up was the MadHawk300. The CX3 and Foamy P-51 are both bound to the same transmitter, so I could not fly the CX3 while the transmitter was in use. I’d done some tuning on it, adjusting the motor. The last failed flight attempt was dashed when on run-up the main pinion began to slip at 1/2 throttle, keeping the heli from getting off the ground. I’ve since lock-tited those motor motor screws.

It few well. Adjustments I made to the swash gave me some really nice control. At higher speed and throttle, helicopter flight dynamics are not at all intutive to a guy that’s used to fixed-wing models. But it still went well, with a couple of hard landings, no big deal.

Then, it happened. While at the east end of the part, close to one of the Pavilion buildings, the tail suddenly started to swing wildly, it accelerated upward, then nosed rolled right and slamed into the pavement at near full throttle, doing quite a number of the landing gear and main rotor blades.

Madhawk 300 with broken landing skid.

🙁 Nothing that was too tough to repair, but I didn’t have the wrench to replace the rotors on site.
Toasted main rotor blade on the Madhawk 300.

At this point the battery on the P-51 was running low. I recouped the transmitter and started to fly the CX3. It was flying very nicely. Nicer than the Madhawk in fact! Zoomed round the park, turned on and off the model navigation lights, did some high speed passes, landings, just some fun landing.

Then, it happened.

Right in the same place the MadHawk had trouble, the CX3 started to go crazy, and started to go into the TBE death spin. I tried to regain control but no luck. It accellerated upward, then nosed over and went straight down, nose first into the ground at full throttle. 15′ was more than enough room for it to gain some momentum.

CRUNCH. It was not a nice scene. The following photos are after I attempted a field repair on the fusalage to fly again. Unfortunately it would not happen since the radio and transceiver were no longer talking to each other.

Once home, I tore down the heli (I’m getting far too good at this) and discovered that the radio receiver took the full-force of the crash. Part of it’s case was ripped off and one of the dipole antennas was missing. Oh oh!

Helicopter on the operating table. Trying to get TX and RX to talk to each other

Removed the plugs from the Spektrum AR6100e receiver in the heli, plugged in the 3-in-1 mixer, checked response. The mixer would not show it’s green ‘lock’ signal. It was not until later that I noticed that the signal lock LED on the AR6100e’s front was actually missing. But it was at that point I realized, that not only was the body smashed, the lower section of the frame mounts for the battery are broken, but the receiver is, completely, shot. I’ve broken at lot of things crashing R/C aircraft, but never destroyed a receiver. It’s at this point I’m thankful for using Spektrum R/C equipment. Replacements are 1/2 that of Futaba or JR radios. Still, it’s a $55 part. Ugh. 🙁

Close up of AR6100e broken receiver (unmounted) and 3-function mixer (mounted)

I don’t want to order a replacement receiver unless I *know* that’s what is broken. So I dug up the AR56200 full-range receiver I have, wired it in to the heli’s remains, and tested. Viola. 3-in-1 mixer lock and receiver lock. It’s a go. Now I just need to decided where, and when, to buy a new receiver. In the mean time, she’s out of commission.

At least I still have the MadHawk300 to fly. And if I crash that into pieces, well.. I’ll just say I have a contingency plan arriving for that soon as well. ):

What's next!?!

CX3 repaired and flying again!

The Blade CX3 is repaired and flying again! The $22 aluminum swash plate repair, actually has the thing flying better than it did right out of the box!

E-Flight OEM Plastic Swashplate E-Flight Upgrade Aluminum Swashplate

Here is a 3 min video of first test flights in the studio, and finally my 8 year old attempting to fly it, for the first time, outside! The crosswind was playing havoc but he did a pretty good job of keeping things together. I think he’s going to be a good pilot some day.

Even though it’s a Toy Co-Axial helicopter (a $200 “toy” to be exact), with the upgraded part, it’s a joy to fly. There is something so therapeutic about an activity that puts nice big genuine smile on your face. And in the end, what price is too high a price to pay for some joy? 🙂 Even though I’ve “outgrown” this helicopter in about 1 week of intense practice, I still want to keep it around, and even put some more upgrades on it! Such as this cool LED strobe kit I’ve seen on the web. Here is a video from a guy that I think, sells the best of them:

Here are a few pics flying it outside, just before dark. Shot with an f2.8 200mm lens, 50D camera set at ISO1600 and roughly 1/30th second shutter speed. Despite the slow speed and high ISO, I think the shots are work posting.

Blade CX3 spooled up and ready for takeoff.

Blade CX3 spooled up and moving out. Still in ground effect.
Blade CX3 after battery change, ready to go again.
Blade CX3 in flight.
Blade CX3 flies overhead.

Good times, bad times, upgrading and crashing the CX3…

Good times. The Blade CX3 is one heck of a fun bird to fly.

The first update today was to add the factory heat sink for the main motors.

E-Flite CX3 heat sink

After removing one of the motors, installing the sink was pretty simple.

Heat sink install 1/2 complete

Motor re-installed and bolted back into position:

Motor re-installed.

The fame looks a little naked without the body installed. But it does not take long to put it back together, and ready for flight.

E-flite CX3 with body removed.

A little time lapse video of re-assembly:

Ready to enjoy some indoor heli flying fun.

Completed bird, and Spektrum DX6i flight controller

Well, it was, until the plastic factory swash plate decided to separate. I’d been fighting with adjusting the swash links most of the evening, after putting the heli back together again. I thought that maybe I’d bent a servo link rod during the heat sink install, so I worked on adjusting the cyclic/swashplate links.

Trying to stop a hard forward and starboard liftoff, and full rear cyclic would barely have any effect. It was not until an hour or so later I noticed that the plate where the servos attach was separating from the bearing and main rotor shaft. Duh. This explains why 2 directions worked great (pushing up on the plate) but the opposites failed (pulling down on the plate, but the upper bearing remained in position, thus no control. No control, but one check of an exciting crash!

The official term for this is TBE (toilet-bowl effect). Not fun. There is quite a discussion of the problem HERE. Once I discovered the problem, it was a matter of deciding how to solve it. There are a couple of solutions.

First of which is a pretty inexpensive factory replacement part.

Stock replacement swash plate.

Second is one of the CNC or cast metal solutions from E-Flite (the original manufacture) or other sources. Research indicates that the E-Flite is the one to buy.

E-Flight aluminum replacement swash plate.

Fortunately, there are plenty of other heils in the shop ready to fly.

Blade CX3 (left), Exceed-RC Madhawk 300 (right)