The stabs were fixed for several reasons -

1> Weight - the hardware and individual mounts for two stabs is considerably more than a single piece

2> Precision and Simplicity - the fuselage can be jigged and cut during manufacture to set the incidence, reduces variability that a wing tube socket could induce. The glued stab also stays put eliminating the common wing tube socket loosening that most planes experience. Note that the EF Yak had a big problem with the stab tube sockets that required rework to reset incidence.

3> Cost - two pieces cost more than one and QQ / Wayne wanted to keep the cost down and profit up


Personally, I hate removable stabs, they are a pain. The only advantage for them (other than to remove them if you have a small car, etc) is that the incidence can be adjusted relatively easily. Once in place however, I have never taken mine off for any reason so having all that extra hardware is nothing but a weight liability and a maintenance problem. Every one of my planes developed stab tube play so I glued them in place anyway.

DP