Hi all,
And here some update on Hustler`s flight testing !
I really encountered a big problem - the Jetsmunt M250XBL reliably flamed out when pulling the throttle stick back from above half power ( leading to two successful dead stick landings ! )
Now why did this happen - it is just because the standard settings from Jetsmunt for the ECU DOES NOT work !
They are using the same pump for their turbines from the M120 up to the M250 with the same ECU and programming
This cannot work - the M250 has so much more rotor inertia compared to the smaller engines that the ECU cuts down the pumps RPM much too fast and hence reducing the fuel supply much too apruptely
Consequence - the M250 will flame out reliably when pulling the throttle stick fast back
I could reproduce this behaviour on ground several times - fast decceleration mode on that ECU is just way too fast for the big M250 !
I went back to slow deccelaration on the ECU`s programming and now the motor runs just perfect throughout the whole range
Accelaration in fast mode has not been any problem !
Of course my flying style has contributed to the above problem - I do fly agressive aerobatics with lots of powerchanges involved !
The second problem - the tires are not clamped together by the rim halves enough to allow full braking action during landing rollouts
The tyres were turning on the rims - I have fixed that as well !
And now guys - I have Hustler just were it should be - a perfect and insaningly fast and powerful flyer it is !
The difference to Firebird is really not that big - Hustler is a bullet as well !
Approaches and landings are easy, but even with all those flaps at 50 degrees and beeing at idle from half downwind it will float forever !
I have emailed Jetsmunt about my experience and asked them to do some bench tests with a M250 just to veryfy my findings - no response !
Again and I am pretty sure about it - the M250XBL should not be sold with the deccel setting on the ECU beeing fast !!
see you
hans