Not much posting recently. With winter settling in there has also been a little less flying in Canberra as well. Still trying to get out most weekends.
Mini Pulse XT
On Friday night, after thinking about it for some time, I finally weakened and bought a new Eflite Mini Pulse XT. Some reading on the net had convinced me that this would be a nice fast ARF Balsa/Ply plane, which I was seeing as a quasi replacement for my StevensAero RV4, but maybe slightly more aerobatic. I have to say I am impressed with the kit. Came from my
lhs.
Lots of others have written about how complete this kit is, I spose the best thing I can do is talk about how long it took me to put together. Including soldering up the speed controllers connectors etc about 6 hours. I've never had a plane go together even close to that quickly.
I decided to get the Eflite 480 brushless rather than the 450. The 450 just didn't seem like a lot of motor to me for $70 odd dollars (around 180 watts peak power), while the 480 for only a couple of bucks more pushed the power up to around 250 watts peak power @ 910kv). Because the MPXT is a heavish plane (850grams or so takeoff weight) I was after that extra punch. I certainly got that.
With a few washers to space the 480 just fit the existing motor mount for the MPXT, which helped greatly so I didn't have to frig around. One note - make sure you locktite your motor in place..., more on that in a minute.
Anyway, I took her down for her maiden this morning using an elegance 3s 2200mAh. After getting some flying mates to double check that all my controls worked correctly I went to taxi out. She started to turn left, I feed in right rudder to straighten her, and suddenly she bucked over to the right. Aborted the takeoff, and went over and checked her out. Just the weight of the plane shifting sideways had made one of the wheel axles bend - weird. That didn't bode well, but I straightened it up and got her ready to taxi again.
This time I was a little less ham fisted with the rudder and held her in a straight line as she gathered speed. Shortly thereafter, and well before I thought she was ready to rotate she lept into the air. I powered up and pulled away from the ground. She took a few clicks of aileron trim and quite a few clicks of elevator trim (like a lot) to get her flying straight and level. Thinking about it afterwards I'm wondering whether perhaps the ailerons were hanging down just a smidgen acting like flaperons, or maybe she was tail heavy (although CoG was good according to the planes).
Once she was trimmed she felt very solid in the air. Much like the RV4 - just a real feeling of authority and stability. I put her through a few basic aerobatics, hammerhead, snap roll, loop. With that 480 I found I was rarely above 1/2 throttle. She seemed to have unlimited vertical, although the ability to hover her was limited due to her quite small control surfaces. She could also pull monster loops (like 20 metre diameter no sweet at all). Big motor turning a reasonable big prop.
Anyway, just as I was really starting to enjoy myself I heard a "whack", and then an instant later, a louder "whack". I closed the throttle. As the plane flew past downwind I noticed the prop bent back about 45 degrees beyond where it should be - that doesn't look good. Fortunately I had already praticed my stalls, so had a reasonably good sense for the plane. I sent her downwind until I thought it was about right, and turned her back for final onto bitumen. Dead stick on a new model - nice.
I should have let her go another 10-20 metres on the downwind (she glides quite well). In the end I got her down with only about 10 metres to go before the dreaded ditch at Kambah, but I got her down, fed in some rudder and kept her out the ditch.
After flight inspect revealed that the motor had shook lose the screws that secured it to the mount (lock tite you idiot). The fibreglass cowling fortunately caught the motor during its escape attempt, although not without a little cosmetic only damage.
Not exactly a perfectly successful maidn, but the plane is in one piece, and the remounting the motor should be straight forward once I find the right screws.
The 480 seems to make the plane a monster. The plane has massive wings, she is well behaved across a wide speed profile. It would be nice if she had some more aileron authority, but all in all a plane I can't wait to fly again.
MicroseetherI continue to have grief trying to get my microseether in the air.
On Friday I built a trike for her to launch from - that didn't work. She slipped of the trike as soon as any speed got up. So, I tried hand launching her.
Ground dancer gave her a perfect throw and I went to spin up the motor... a knocking sound - I shut the throttle, and she plowed in to break her nose (again) - more broken noses than a rugby tour. While trying to taxi her on the trike the prop had struck the trike once or twice, and worked it's way lose - I didn't check it before launch, and so despite a perfect launch she went in.
Last night I built some under carriage for her. That didn't work out today either. As I tried to taxi up to speed the wheels weren't perfectly straight, she started to turn, and as the speed came up she overbalanced.
So, I tried hand launching again, this time with motor running at 1/4 ( a strict no-no according to the plane's manual). I launched it without busting up my fingers, I got the motor up too speed, but just couldn't pull up fast enough for her to clear her nemisis - terra firma.
Another broken nose... There are still two more things to try. Motor thrust angle - the plane's designer warned me to make sure she has the motor shaft coming up from the tail if anything. After that, I'll try bungy launching. After that I'm all out of options.
The one time I've had this plane flying it was brilliant, but I am having real trouble getting her in the air.
That's all the flying news from here that is fit to print.
