Addiction-X arrived this morning

[Andy Harris]

So finally the Addiction-X got to maiden today. However the outcomes were not so good.

 

Wickedly quick take off, almost instant, well behaved with lovely tracking, nicely axial on the roll. Slow speed flight down to the point of going backward against a 10mph wind.

 

It all went wrong when full rates were selected, on the first roll one aileron stopped in an odd position. It was like flying with a single barn door as a flap and trying to balance the ailerons to suit.

 

I coaxed it to the ground and we had a good check, we made an assumption that I didn't tighten the servo head screw enough, reset the servo arm position and tried again, same thing ailerons out as soon as high rates selected.

 

A few sweaty moments later she was back on terra firma minus a tail wheel.

 

Further investigation revealed that the servo arms were slipping. These are brand new heavy duty Alszone hitec servo arms, used plenty of times before with no issues. Tried holding back the ailerons and sure enough the arms slipped on both sides.

 

Even the static wash from the motor can make them slip. However these ailerons are very very very big for mini servos.

 

So tonight I'm searching through the internet for metal/alloy servo arms.

 

 

[Andy Harris]

I sourced some heavy duty servo arms from Hangar 9. Here you can see the old and new:

 

Unfortunately because it is a US part the thread sizes do not match up, therefore I had to fettle up a brass ferrule:

 

The new linkages certainly feel much stronger, I hope they will survive the flight loads, here you can see the new linkage in place:

[Andy Harris]

Yesterday I finally managed to get three decent flights in on the Addiction-X.

 

The new servos and arms were up to the job in a 12-15mph (cross) wind. All the throws and rates are as per the manual. First test flight started with low rates and finished with high rates to check that the ailerons would not blow back under load.

 

Take-off is instant into wind, less that 1metre of roll.

 

The first flight ended with a rapid battery induced dead stick. Landing was simply a case of sticking the nose into the winding and making a vertical elevator style descent to the runway.

 

With low rates selected the Addiction-X is ultra docile, far more so than the smaller Addiction. On high rates the AddX comes alive however its not as lively as its smaller sister.

 

The AddX can be flow with full rates for everything. The wind had dropped to around 8mph for the second and third flights. I set the timer at 6 minutes and proceeded to give the AddX a good thrashing.

 

Even with a 600W motor it doesn't seem fast, although it will prop hang at very low throttle, in fact I found it tricky to reduce the throttle far enough, there always seemed to be a little bit of climb happening. The pull out is very crisp.

 

The roll rate is superb, its easier to stop the AddX where required. Loops and Bunts are simple, with the rates in loops can be made very very smaller. Large loops give plenty of time for any corrections needed. Looping into wind is an elevator only operation.

 

Initially I thought the knife edge took a little more effort than with the smaller Addiction, however I don't fly the smaller version if the wind is in the double figures. As the wind dropped I found that the KE was very easy, even correcting for the cross wind.

 

As I packed up I was thinking:

 

a) reduce the expo on the ailerons and elevator (more lively response)

b) reduce the pitch of the prop so that the throttle can be pushed forward more (giving a wider range)

 

On reflection the Addiction-X really does minimize pilot workload. Even with a variable wind buffeting around I was flying lower and lower with confidence.

[Lee Smalley]

Andy i have just completed mine and HS82mg have been fine there is no slippage under full power, i think the problem stems from using the wrong arms, the blue ones are for JR servos HS82mg are Hitec the spline count is not the same, the arms you should ahve used are the black ones like mine these are for hitec and do not slip, in your own picture you can see Jr stamped on the arm

Edited By Lee Smalley on 30/06/2011 00:12:44

[Andy Harris]

Lee

 

Thanks very much, I also had the same arrangement on another model that was likely to cause a similar problem!

 

Going back to the AddX on the 82's I had the problem of them creeping back to neutral. This happened after bench testing, they got very hot holding position against the thrust of the motor (the test wasn't excessively long).

 

Cheers

 

 

Andy

[Lee Smalley]

Not had that problem mate