Surging... couldn't honestly say what... but I have noticed that just recently on the tail motor..
I have a third hand vice... that I mount the heli on.... it is set up that I can put the heli
on and able to test the control tabs on the TX such that the heli can spin around and trim etc....
and I have notice such a surge on the tail motor... but my tail motor right now is not stock
ie after market Walkera replacement... see my post..
http://www.rcuniverse.com/forum/m_6899234/tm.htm

You might at some time get such a device and mount the helicopter to it upon a "Lazy Susan" turn table...
it's great to test the tail motor and how and when you increase throttle the tail and the gyro
work together.
You will see... unfortunately... that they don't always work together consistently.
We are talking "cheap" electronics... as compared to $600+ helicopters Tx and Rx's.

I don't know if the surging is from RF interference or what...
maybe rattling around the gyro in the Rx is causing it...

But I was in the backyard working on my hovering and all seemed ok today.
It's between 10'f and 20'f... and windy... so I am just working on low hovering and control...

Swashplate coming apart.
Once it comes apart it will continue to do so...
I have found a fix in that I put tissue paper in the hole in the lower part
and push it together.. and that will hold it for a while.
It is a press fit... and thusly you can push it together again... I have a lot of times.

Next fix idea, that I haven't done is using the epoxy that is in a roll that you cut off
a section and mix it together in your fingers.... and shoving the epoxy into the
the underside hole in the swashplate so that it can't expand and come apart.
That is... you have two parts to the swashplate that come apart...
The lower with the bearing and the upper with the plastic press fit that goes into the lower.
Once the two pieces are connected... you would flip the swashplate upside down... and
shove the epoxy into the "hole" of the upper piece.. so that it can not expand and separate
from the lower piece.
Obviously being careful not to get epoxy stick mix you are using on any of the bearings parts.

And then of course is the next best option...
And that is learning how to fly and not crash all the time.
But I'm the last one to preach to that... ask my parts supplier... they just
bought a Porche from all my "donations."