Turbine Test Runs - Good News...Bad News...


Jet gassed up and ready for turbine starts and run ups. Good news...X-45 starts up and runs perfectly. I did two starts with runups to max power and extended runs at idle. There were no indications of any heat damage inside or out. I think the pipe, bell mouth, and pipe tail mounts are working well. There seems to be plenty of airflow in and around the turbine bay and aft fuse for heat removal. I expected this would be the case since there is plenty of room around the turbine and pipe inside the fuse.


The top cheater holes would start to open at about 1/2 stick and never fully opened even at max power. I expect with flying airspeed going into the intake to raise internal air pressure the doors may not open in flight at all.


Bad news...on both shutdowns the electric motor would not stay engaged to the turbine to spin the rotor. It made strange noises and RPM would flux between 0 and 5000 rpm. Also the bottom of the turbine was wet with fuel that dripped out of the hatch. I think there may be a small fuel leak in the front under the cowl that is getting on the clutch and causing slippage but really don't know. It happened the same on both runs. This photo is after the 2nd run. The wet fuel has been wiped off but I don't know where it is coming from. I trimmed and reseated the fuel tube in the Festo fitting after the first run but still had fuel drips after the 2nd run same as the first. I have 4 X-45s and this is the first issue with any of them.

Ideas anyone?