Re-motoring the Ascent

My Ascent has been kind of a weird experience.

Ascent overview
Not a bad looking bird, by any stretch

For those who don’t know/remember, the Ascent was a Tower/somebody ARF with a built-up wing, holes in the wood sheet tail, fiberglass fuselage and probably tail boom (it’s painted and I’m leaving it alone.)

The power came from some off-brand S400 canned motor. Slot in the fuselage was set up for a 7 or 8 cell pack. Came with the classic crap-tastic Chinese folding propeller.

The thing sat in a box for a good long time until I got some time and interest strung in a row to slap together the wing and tail and hot glue in a couple of MX-50 servos since the wells had been sized from some unobtainium micro that wasn’t one of the dozens in my stock.

Then Something happened and I never flew the bloody thing.

Jump forward again, and nobody is flying canned 400s anymore and old-fashioned KR600 packs are rare. Weirdly, being incredibly incapable of letting things go, I still had some 8-cell packs, new-old stock with no connectors. So I slapped a connector on the end, dug out a 20 amp controller, and strung a new Spektrum receiver in the thing to see what flying old school was like.

It sucked. Heavy. Low power. doggy. I think it was mostly because the motor was some non-Graupner motor of whatever voltage was available for production at the time, since I did cycle the pack and it was okay. It flew, but not in a fun way, especially when the crap-tastic Chinese prop decided to part ways with the yoke and pop the motor mount out of the fiberglass fuselage.

So, after re-seating the motor mount, I dug around in my project box and found a speculation motor I’d picked up at Phil’s back in the day. Apparently there was a pusher model called the F-27 that used an in-runner hotrod motor that just happened to bolt into a S400 motor mount. So I picked up a 25 amp Hobby King speed control, stuffed an 1800 mAh 3S pack in (it fit in the slot), chucked an Aeronaut 7×4 folder on the front and committed aviation again.

Okay, this time it flew like hell-bat out of-one each. It also sank like a brick with the motor off. And the way the prop was talking, I knew I was pushing my luck. Got it back down and found the prop pivot bolts had been bent. Eep.

So, too much of a good thing. Ascent went back into the corner and I started playing with ideas regarding batteries and motors.

Espritech happened to have some sales going on a while back on AXI motors. I went ahead and speculated on motors again because, apparently I’m addicted to buying expensive things to put in boxes on shelves. In this case, however, I managed to grab an AXI 2217/20 long can motor. And it turned out that, after thinking things through, it was actually just what the Aspire needed.

Now, mind you, this meant having to order a prop/spinner adapter from ENGLAND because, “There’s no market for a 40 mm spinner with a 3.17mm shaft motor” per the people who sold me the motor with the 3.17mm shaft. Regardless of that, though, I was able to provide a set of 8×5 blades from my stockpile to go with my nice imported spinner. The speed control, receiver, and servos remained the same, but the battery downsized to a 1000 mAh 3S pack.

View of the motor through the canopy
You can see the rotating back end of the AXI

I re-maidened the re-motored Aspire Sunday and then flew it again Tuesday at the weekly club get-together. I finally have a model that flies like a glider. My take away is that the weight really had to come down and I had to shift my mental focus away from a pack that was the same dimensions and actually look at the capacity and the motor draw instead.

The 1000 mAh pack drops into the 70% remaining capacity range during fairly active 8-10 minute flight and the performance is perfectly acceptable. Just need to improve the rudder throw a bit to improve yaw response. Elevator is great. Plane is really visible with its transparent red covering. That covering is also robust, as testified to the fact that it was not punctured when my tool box tipped over on it during the ride home Sunday when some idiot cut in front of me and forced a high-g deceleration maneuver. The structure has held up remarkably well, for as long as it’s been in storage. And even blowing the motor mount out didn’t do any significant damage to the fuselage: it just buggered up the gel-coat around the front edge as it exited.

Things I just don’t like about this airplane: Why is the canopy screwed on with little sheet metal grub screws into fiberglass? Who thought that was a good idea? And 4-40 bolts to hold down the back of the wing with easily lost and probably unobtainable 4-40 fender washers to spread the load? Especially when I think the trailing edge in the area the bolts goes through is hollow? Not the brightest.

The only thing I can really say about this is, some planes are just long, expensive journeys to get where they were supposed to be out of the box.

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