Just come across this thread. Am a new Zlin Shock Cub owner. Waited ages (over a year) for the 915 and finally went for the 914; very satisfied with the decision. Desser Aero Classic 31” (more like 29”) on Beringer 10” rims and a fat Matco tail-wheel. Really enjoying it. We did have and continue to have teething issues but are working through them. General build quality is excellent but Zlin really should have picked up more of the niggles before it left the factory.
We had significant engine over-heating issues as soon as we started flying her. The oil-cooler radiator was 50% blanked by the cowling and oil temperatures were way too high. The local agent’s engineering shop did a great job of modding the cowl which resolved that issue. CHT’s were way too high - the plumbing to the 2 engine radiators was not at all great - ported to the two radiators through a T-piece junction which resulted in very unfavorable fluid dynamics. The local engineers re-plumbed the coolant, routing the total flow through one and then the other radiator. Simply put, once this was done all engine cooling issues were over.
Other, currently unresolved issues still in the process of being resolved are:
* The rear control stick impacts the forward seat to the extent that forward elevator travel is restricted by almost 2 inches. I’ve removed the rear stick (it has a quick-disconnect) as it really was unsafe. Working on a replacement stick with enough bend to avoid conflict with the front seat.
* The Beringer brakes are just not ‘grabby’ enough. I’ve wound the adjustment knob to the maximum and they’re still well below where they need to be. The brakes hold the aircraft against power but just barely and are ineffective for proper ground maneuvering, especially in a crosswind.
* I’ve never been able to select the third (full) notch of flap in flight. It goes to the notch on the ground, with no aerodynamic load. The flap attachment arm is striking the fuselage panels on either side on the way to the fully extended position. The factory insists they got full flap during testing but I simply don’t understand how that was possible. We’re going to cut a section out of the fuselage panels which the arm passes through and that should resolve this issue.
I really do feel the above 3 issues should have been identified and resolved during testing at the factory.
Nonetheless it is a fantastic machine; the 914 is a great compromise between a reliable, well known power-plant, weight, cost and fuel-efficiency (averages around 20 litres/ just over 5 USG per hour). We’re still exploring the envelope, stall is docile and a non-event, occurs well under 20 knots (with just the 2nd notch of flap) and results in a rate of descent around 600 feet per minute, power-off, stick fully back, no wing-drop. Application of sufficient engine power reduces the rate of descent. No doubt she’ll land in the hover with around 20 knots of headwind. Still building courage and experience before we go there.
Here’s a snapshot -
https://www.facebook.com/562437460/posts/10156024979342461?s=562437460&sfns=mo