Maiden Report:

Less than ideal conditions at NCAR (E winds 10-15 mph) and I ended up being the only one there, so no video. Sorry.

Two successful flights and landings: One lasting 2 minutes and One lasting 10 mins (As I said less than ideal wind speed and direction).

Initial impressions:

This thing needs decent wind (15+) and/or lift to fully spread its wings, but with either of those two conditions present this thing gets moving and responds amzingly.

First Flight: Immediately after my first launch I needed to add 4 or 5 clicks of up elevator to take it out of a gentle nose dive despite all my surfaces being flush. As I mentioned this thing needed alot of weight to get the COG at 68mm or so. After that adjustment the plane flew virtually hands of, but the wind dissapated and I had to land.

Second Flight: My second flight lasted much longer as the wind speed and direction cooperated for about 10 minutes. Man this thing repsonds to lift amazingly compared to the Speedo 1.2. The handful of thermals I managed to hit lifted the plane quite dramatically. I was going in for my second landing and ran into a thermal that lifted the plane back up for another 5 minutes of flying. This plane is extremely responsive and goes right where you point it. The few rolls that I was able to pull were quite tight and fast and I imagine this will only improve given more wind.

My only concern right now is how this thing sinks like a stone when the wind dies. I am wondering if the COG actually needs to be back even further, like 70-75mm? Just feeling the weight of this plane balanced at around 68mm and you know that it will need some wind to keep going. My question is if this plane is just designed for higher winds or does the COG just need to move back. Like I mentiond, Cody at Skip Miller and R2 said 65MM or so to start out. Yet if this thing can fly in 12 km/h wind like the website says then I think the COG needs to move back and a decent amount of weight needs to be taken out. Then again I do not claim to be an expert by any means.

COG: 68mm
Ailerons: +17mm - 8mm
Elevator: +10mm -10mm
Rudder: +10mm -10mm

Weight still pending until I get in front of a scale. Sorry.

Cheers for the review!

Great to hear it can fly good! I enjoy a challenged when im flying and this sounds about right! (I have a Banana at present, but it flies too easy!)

So is it really tail heavy? I dread to think what the pro version will be like =/

Originally Posted by GR8FOLDED;21265426.....................

[I

First Flight: Immediately after my first launch I needed to add 4 or 5 clicks of up elevator to take it out of a gentle nose dive despite all my surfaces being flush. As I mentioned this thing needed alot of weight to get the COG at 68mm or so. After that adjustment the plane flew virtually hands of, but the wind dissapated and I had to land.[/I]
...........................

Needless to say, that indicates the CG is too far forward. How did it perform in shallow dives? Any tendency to zoom?
Correcting the CG will result in less AUW for sure due to the nose weight removed. However, the most significant gain is the lowering of the stall speed and the improvement of slow flying efficiency, which is what you are not achieving with it forward. I'm not in favour of "starting with the CG forward", which is repeated like some sort of mantra. It makes the maiden flight harder than it might be if the CG calculations were done on the bench and then set.

Jim.

Hey Jim,
You're spot on. The plane was stalling / tip stalling at a speed higher than I expected. It caught me off guard initially and I needed to have the plane really moving fast to prevent this. As far as a tendency to "zoom" in a shallow dive, I'm not quite sure what you mean. When I put it in a shallow dive it seemed to level itself out and climb a bit due to the up elevator trim I had adjusted originally. When I cancelled that out with some down elevator trim, the plane moved extremely fast. However, when the wind lightened the plane tended towards a gentle nose dive again, leading me to believe, as you said Jim, that the CG was too far forward.
I have now removed the two lead blocks that you can see in my photo and it looks like it is now balancing closer to 75mm. Not sure what to expect when I fly it next, but at least it feels less like an actual "lawn jart" now. I'll post again when conditions are favorable. Any other input is definitely welcome. BTW the lines/shape on this plane look quite nice when it's ripping through the air... Should be a treat in real wind with the CG dialed in.

Originally Posted by GR8FOLDED

................ ............ When I put it in a shallow dive it seemed to level itself out and climb a bit due to the up elevator trim I had adjusted originally. ................

That's what I mean by a tendency to "zoom".

Originally Posted by Jimbello

Needless to say, that indicates the CG is too far forward. How did it perform in shallow dives? Any tendency to zoom?
Correcting the CG will result in less AUW for sure due to the nose weight removed. However, the most significant gain is the lowering of the stall speed and the improvement of slow flying efficiency, which is what you are not achieving with it forward. I'm not in favour of "starting with the CG forward", which is repeated like some sort of mantra. It makes the maiden flight harder than it might be if the CG calculations were done on the bench and then set.

Jim.

+100!!

This maiden report points to a classic case of too much nose weight (CoG too far forward). Your needing to put in a bunch of "up" elevator is an indication of trying to keep up a heavy nose using up elevator trim. Ideally, if the control surfaces are dead level, the glider should be neutral when speed picks up (neither climbs nor descends). I have a strong suspicion 75 mm is going to be much closer to the "sweet spot"...

My girlfriend was kind and patient enough to swing up to NCAR and shoot some video on my iPhone today. If you go to "Original Quality" and full screen options the video is much better. BTW the wind wasn't nearly as "ripping" as it sounded...The iPhone made it sound like that.

http://youtu.be/LWR-IYUtF6g?hd=1

http://youtu.be/Jz1bG_ouh4k?hd=1




I moved the CG back to around 80-82 mm and the plane handled much better than yesterday. As you can see in both videos, once this thing finds lift it climbs crazy fast. The rudder is amazing for hammer head turns at the top of half pipes. I was able to string a bunch together that were pushing 100+ feet high on each end. Super fun...

5 successful landings today with just a small bit of enamel chipped off the nose. I think some glass cloth and epoxy will help reinforce the nose significantly for those of us with boulder strewn landing zones.

Keep a few things in mind: The wind wasn't perfect, I have less than one year of RC experience under my belt and I am still getting a feel for this plane. That said, this should whet your appetite of what this plane can do in a more experienced pilot's hands. Fun all around!

Look forward to the vid.

Originally Posted by GR8FOLDED

..snip... with boulder strewn landing zones.

LOL, was going to comment on those the moment I saw the video. Those are some nice ones. I hope your LZ is a bit more boulder free.

-Jonathan

I checked my Jart LT wing against my Buddy's new Speedo wing. They are certainly identical in planform, joiner location, etc. We did not check precisely but the profile also looks the same.

I will buy one for a spare set of LT wings.

Took the Speedo Pro out yesterday in 5-8 mph winds and was shocked how well the plane flew in such light winds. Even better than the original 1.2. A large part of this is due to moving the CG back to around 75-80 mm and taking a bunch of weight out of the nose.
Overall, I think the performace of this plane trumps the original. Now I just need to figure out how get some EPP wings made and reinforce the nose of the plane which has been nicked up a bit by the rocky LZ out here in CO.

Originally Posted by Greg Beshouri

I checked my Jart LT wing against my Buddy's new Speedo wing. They are certainly identical in planform, joiner location, etc. We did not check precisely but the profile also looks the same.

I will buy one for a spare set of LT wings.

Can't you buy just a wing set instead of the whole plane ?

Originally Posted by catfish

Can't you buy just a wing set instead of the whole plane ?

Did not try, but I doubt it. That would probably take a special order. I will give the fuselage to my Speedo flying friends.

Me and my buddy Bob both maidened our Speedo pros yesterday afternoon. Success! Both flew with little trimming and returned to earth unscathed. Winds were around 10 mph which is a little light for this plane. I'm looking forward to more wind to see what it can really do, but so far so good. A remarkably good plane for $125.

Here are random facts about my build:

AUW 24.5 oz. with a 4 AAA pack and 4.5 oz. of lead in the nose. I coated the inside of the nose with wet gorilla glue, poured in 3.5 oz of shot, and stuck in the battery wrapped in saran wrap. The glue foamed up around the battery making a secure mount and a solid nose. Once dry I pulled out the battery and put ~1 oz of flat lead weights in the front of the battery hole to balance.

CG at 80 mm from the LE at the root. This gives an absolutely straight dive with no pull out at all. Flies inverted with little down stick. I started with the cg at 75, but level flight required some up elevator so I removed 3/8 oz lead from the nose. It's a little more tip-stally at low speed than the original (which isn't at all), but this should be no concern with adequate wind.

Stab incidence came out at 1.2 degrees. I used 1/64 shims on the top and bottom. The stab slot was not square so it is shimmed more on one side. Have the wings on when mounting the stab so you can tell it's level.

Servos are HXT900's, mounted to the servo covers with the double sided foam tape supplied. I did not use the clear spacers provided. The servos just fit beneath the top covering. I taped the covers on instead of using screws. I used fiberglass contol horns instead of the screw ons provided. I will use them on a plane needing beefier hardware.

The double pushrod assembly to the split elevator can have a lot of friction through the rear fiberglass guide tubes. If the tube is inserted into the fuse it comes out at too much of an angle requirng the pushrod to make an S bend. I fed the two pushrods out the holes and mounted the elevator control horns. Then I pulled the pushrods out of the control horns and slid on the fiberglass tubes til they butted up against the front opening on the fuse and glued them in.

The canopy is mounted with a 1" longer metal rod held on with a blob of epoxy in the middle.

My wings were perfectly balanced from the factory.

Just got a Speedo 1.4, reading here about weight. I am considering connecting the 2 elevator halves and installing one lighter pushrod. I will have to make an opening in the rudder for the connector rod. I would perfer to have a bigger battery than lead, will have to see what configuration weighs out best.

Gorrilla glue is great just be aware that it expands ALOT, it could have easily split the fuse seams.
Rick