Hello, as a (european, not taiwanese) modeler with no affiliations or any business relations of any sorts with ATJ or other rc-related companies, I had a meeting with ATJ's representative Joseph in November at their small office in Taipei to evaluate and decide on purchasing a 120ti.
Joseph and the rest of his staff welcomed us very warmly and answered my questions over the engine patiently for over one hour. He let me check out every piece of the engine, rotating assembly, compressor guide vanes, and all, but he provided me with an older version (ATJ 120, not 120ti) combustion chamber, because he didn't have one of the new engine's available at that time. Communication was difficult at times because my chinese is extremely poor and his english could use some improvements We eventually had to ask my wife, who speaks both chinese and english, to help us out for part of the conversation (this is probably one of the biggest issues one could have with ATJ).

Engine parts looked top quality and very carefully manufactured and inspected. He confirmed they run X-Ray scans of all the wheels as a routine. The combustion chamber is also made out of inconel (same as the turbine wheel) as opposed to other brands of turbines which rely on less durable steel.

Joseph is extremely competent and my average knowledge (Iam just a software engineer with a passion for airplanes and turbines) could only come up with questions that seemed trivially answered by him (just as expected).

When Ifinally asked to see a test run, he packed up the test stand (which by the way is the one you see in his videos on youtube, just search ATJturbines) and drove us to a highway out of town. We stopped on the side of the road and he fired her up right there. The engine fired up right away and displayed a solid thrust of 12+ kg. He handed me the radio and Itested some transitions - 0 to 100%, 50% for a couple seconds then 100% and 0% etc. Both the engine and the electronics performed flawlessly and, I'd say, remarkably. This is what Iwould call a real "on the road"test

On the way back Iasked some more questions, namely the availability of an FODscreen (the answer was, make one yourself, it's cheaper and works just as well - if you want I'll show you how) and the availability of a kero start option (he said it was available, for about 200 USD).

So Iconsidered it for about one month until he gave me a special price offer through e-mail and made me decide to buy it. Went back to Taipei and bought the engine. Before packing it up we fired it up (right there in his office, and that was quite scary to be honest ^.^) and, since everythign looked alright, Ipacked it up and brought it home.

Since this is my first turbine, Iwanted to clear my mind of all possible doubts and run as much testing as possible before heading back to Europe so Ibuilt a test stand, ordered a co2 extinguisher, built a board for all the electronics and fired it up by myself.

Plugging the system to a fully charged 2s LIPO the glow plug (an OS. 8) blew right away (Joseph actually told me to expect my battery would be weaker than his as he was using a big lead acid battery, but this was not the case as the lipo was well over 8v). Replaced the plug and lowered the rate to the very minimum on the ECU start programming, Iattempted a start. Increasing the plug power progressively allowed me to find the lowest setting for reliable ignition to be at about 25 (original setting was 35).

After the gas ignited properly, she spun up to pre-heating and then shut down giving me a "bad start" error. This happened 2 or 3 times then the engine actually started properly.
It then ran flawlessly just like the one Itested "on the road" so Ishut it down to straighten out the startup issues. Cooling was also perfect.

After this start there was no way to turn it back on as the gas simply would not ignite. Fearing I'd lowered the plug power too much, Iraised it, with the only result of blowing a second plug. Ieventually figured out gas was not reading the engine at all because the gas solenoid was not opening.

So I removed the solenoid from the circuit and connected the gas tank directly to the engine, driving the flow manually and the gas ignited right away (with a new plug).
The same trouble with spooling up the engine during the transition from gas to kero happened with a few failed starts. So Iincreased the "pump start"setting from "AUTO+2" to "AUTO+5" and with this change the engine spools up perfectly every time.

About the solenoid Icalled Joseph directly on his mobile and he was so kind to provide me with disassembly info and pictures to look for anything that could have gotten the valve stuck.

So Idisassembled the valve and found nothing wrong. Running a resistance test showed an open circuit and, since I was not into disassembling the tiny electronic part of the valve while it's on warranty, Ijust mailed it back to Joseph. He returned it within 2 days and said there was a problem with the internal power lead connection. These valves are the original solenoids supplied directly by Xicoy by the way.

Now that the initial issues have been straightened out, the engine seems just perfect under all points of view and Ican't wait to mount it in the airframe when Iget back to europe in April. It's gonna be aFeibao Velox XL thunderbirds scheme

Attached are the pictures Joseph sent me while I was troubleshooting the gas valve.

A video of the latest startup & test - the cone glows because it is very dark, the EGT is about 550~600 degrees.
[youtube]http://www.youtube.com/watch?v=huxTN0MnPkQ[/youtube]