Hoyt Park Dr, Sunday 9/13/15

This time I went out to Hoyt Park as I didn't feel like being surrounded by quads again or deal with the wind.  I also went out there in the mid afternoon, hoping that it would start cooling down by then.

For this session I took out the shims between the head block and blade grips to smooth out the rotation of the blade grips, as I remembered they were notchy during assembly. I also pinched all the binding ball cups in the linkage. I was hoping these changes would get rid of the head bobbing that I've been dealing with. I so increased the headspeed to 3500 rpm. I had no luck though, as the heli was still bobbing. At least it's only noticeable in a hover and not in flight, but still!

I was braver with the 380 this time, attempting some flips, rolls, loops, and stall turns!  Now that the headspeed is the highest it can go with the gearing I'm using the heli feels much better to me. I'm thinking of trying a higher style setting which is supposed to fly more locked in and sim like, which is what I want. 

My pit table in the shade.  I was flying alone, but the occasional dog walker passed by and one car parked across the street watching me fly I guess. 

SEFSD Session, Saturday 9/12/15

I loaded up and headed out to my official flying field, SEFSD next to Sea World for my 1st session there with the 380.  I arrived about 10:30 am and the helipad was clogged up with quad copters :(. Where have all the helis gone!  I setup my pit and prepped the 380 for flight.  

Quad guy. He's been here every time I've come out since May!

Another quad regular. 

Getting the 380 ready. 

My new motor mount with a bigger heatsink and mini brushless fan!  My motor temps are at a steady 130F now. 

The Goblin 380 ready to fly!

I continued my testing to see if the motor would shutdown, but this time with my fan setup. I flew both batteries for only 4 minutes, then landed and sat on the pad with the motor running, to see if a shutdown would occur. Nothing!  I increased my time to 5 minutes but at a lower headspeed. Nothing!  Cool!

After I felt that she wouldn't drop out of the sky, I started flying around trying out the different agility setting I had in each flight mode. But by this time the wind was picking up and my turns were getting sloppy and the heli was sliding around more and more. So I decided to pack up and head home before something bad happened. 

Will the 380 lose power again?

So this session I was parinoid that the power would shut off again, so I stayed on the helipad for the first 2 packs, then cut my flight time to 3 minutes, landed, then stayed on the pad for 3 minutes. No shutdowns. Next session I plan to increase the flight time to 4 minutes and stay on the pad for 2 minutes.  When I can fly around for 5 minutes, I'll increase the headspeed to 3600, 3300, and 3000, then go back to tunning my Vbar Neo. 

Brought a pit table to work on this time. So much better!

My view of the flight area. 

380 crash landing!

I was flying the 2nd battery when suddenly the heli lost power and dropped to the ground!  I was only hovering at the time and all I could do was turn the motor off, but I guess it already was off?  The heli flat landed and tipped over!  The tail blades got scuffed up, one main blade had a small hole in it, and the boom had a paint chip. Pretty minor damage. I'll probably replace the main blades to be safe. I was pissed about the failure though. I'm wondering if the motor or ESC overheated? Maybe the battery is bad?  It was pretty hot out and I only waited about 10 minutes to fly again after my 1st pack. The damage was minor enough that I flew my last battery with no issues.

When I got home I tested the suspect battery. It was able to hold a constant 20A load with no problem. It's IR and capacity rating are what I would expect. I downloaded the data logs from the flight where the motor shut off. The esc temp peaked at almost 170F.  There were no drops in the BEC or battery voltage.  The only thing I can think of now is the motor was too hot?  Maybe a loss of the radio signal and it went into fail safe?  Maybe the Vbar governor cut the throttle?

I'm going to attempt to run the suspect battery again, but on the ground and see if it shuts down again. I'll need to pay attention to any error codes from the ESC or satellite receiver.  I'm also bringing my temp gun to get a reading on the motor. 

380 Session #2

Well I headed out to Hoyt Park after in hopes of getting rid of the bobble in the main rotor. I tried turning up the headspeed to 3100 rpm but that didn't seem to do anything. Next I used the Neo flight banks to test higher and lower main rotor gains. I set up bank 1 with a gain of 50, bank 2 with 70, and bank 3 with 90. Bank 3 seemed to eliminate the wobble!  I need to try it again to confirm though.

I tried flying around and the tail yaw rate and collective responsiveness seemed weird. I think it was because I was using the sport/beginner mode. I'll need to change that to 3D mode and see if the response feels better. 

I also got my first "crash" out of the way. I was trying to land and either the collective was super touchy or I lost power somehow, and it dropped from about a foot off the ground into the dirt next to the heli platform!  Luckily the only damage was a scrapped tip on the tail blades. 

Also, trying to tune by landing and hooking up to my laptop is a pain. Makes me want to switch to a Vcontrol radio. Hmmm. 

The plan for the next session is:

-change the pitch curve for Normal to a flatter curve for landing. 

-confirm 90 main rotor gain eliminated the wobble.

-perform an auto trim flight

-try 3D agility mode and see if the response is better

-tune tail gain

Trex 250!

I caved and picked up a Trex 250 using a Labor Day 10% off coupon at Heli Direct!  The plan for this is to be a training heli to try new maneuvers with, that flies better than my 130x and is cheaper to crash than my 380 and 550. I'll probably begin flying my 450 less, as it's getting hard to find replacement parts for.

I plan to use the speed control (Castle Phoenix 25) and batteries from my crashed and retired Blade CP, since it uses a similar power system.  I will also use the Brain FC from my 550 for it and install a Vbar Neo with Rescue in my 550 when I rebuild it. 

Goblin 380 maiden flight!

I flew the maiden flight of my Goblin 380, Labor Day, 9/7/15, in the late afternoon. 

It was uneventful, but it did have a head bobble, while in a hover. I hope it was because I was running a low headspeed for it, about 2600 rpm, per the manuals suggestion, for the first few flights, to break in the drive belts. 

The other issue I found was that the motor belt had moved up the main pulley to rub on the frame as it was going by. This resulted in some rubber bits inside the canopy and heli.  Unfortunately I didn't have any tools with me to adjust it, so that ended my flights on the 380 until the next session. 

I repositioned the motor belt such that there's more clearance to the frame and I'll bring some tools with me to adjust it at the field.