I think I read somewhere it weighs 2.4 lbs... but I don't remember if that includes muffler, ignition and ignition battery. Pretty heavy at for a 7 lb model.

But I'd like to see somebody try it, just for curiosity's sake.

?T?hat ws my thought...

I've just joined a new club, and there was one out last Sunday with a gas engine, don't know what size it was.

Did you see it fly? It would be most interesting to get the details on that one!

I checked the TBM website and they list the weight with muffler and ignition as 2.6 lbs (roughly 41.6 oz - check my math). Add another 3 oz for ignition battery and you're looking at close to 45 oz for the engine alone. On this airframe, fergitaboudit![X(]

I saw it fly, but I don't know what engine it had in it, I could only tell it was a gasser.

It wasn't fast, even as fast as mine with the .90. It seemed to have a constant speed, no matter what position it was in, climbing, diving or in level flight...

I finally have my OS75AX running good. I am now using a Graupner 13.5"x8 prop. This seems to be smooth,quiet, and pulls good vertical. I really never understood why this engine wasn't making power. I cleaned the carb., eliminated the filter and richened it a little. This engine doesn't seem to respond to needle valve changes with RPM changes like most engines. I also hate the knocking noise that all OS 75AXs seem to make, but OS says that is normal. Now it is powerful. I do have to keep adding support to the flimsy belly. This plane does fly great though.

Hmm... perhaps one of those ST 90's modified by BCMA to run on gas??

With equivalent displacement, glow delivers more power than gas, of course with much greater fuel consumption as well.

Got mine stripped down for the refurb project, and indeed the fragile fuse belly is in pretty bad shape. Amazing the plane was still flying after the tumbles it has endured at my hands, and I'm lucky it didn't end up as a pile of splinters. The encounter with the wind sock pole did a lot more damage than I realized, so the overhaul is occurring just in the nick of time.

Wings will be ready soon for recovering and I will post photos, then on to the fuse.

The biggest hassle so far has been digging out those pinned and glued hinges. I am going to re-do with CA hinges, but if anyone doubts the security of pinned hinges just try to get these out![>:]

it has been a while sence i have posted here. My plane isnt so pretty anymore and its landing gear was trashed on a dead stick. The man inside about vibrated out so i when ahead and just cut the entire area out. That saved a good amount of wieght.

anyone do 3D type flying with this plane? I am thinking about moving the CG back a bit around the 130mm mark or something. I am hoping it will make it a little more stable in a hover mode. With the plane right now its about impossible to hang it on the prop.

I am also going to be changing out my APC 15x4W prop. I dont think it works right.

I got some options to test. 15x6 wood, a APC 16x4W and a 14x6 3 blade. I am thinking to do more 3d the plane will need something like a 16x5 or 16x6 but my ST90 probably not going to do that at all. perhaps it can handle a standard apc 16x5.

16x4W on the ST90 is going to be the clear winner!! It was like night and day compaired to the other props.

Next tests are going to be messing with the CG some.

Ohh, Bob (i think that was your name). The main wing incedence mod. Do you recall if that helped while performing knifedges? When i pull a knigedge i have to use a up elevator to keep i going straight.

Rich, glad you found the right prop!

Can't say for sure how the wing incidence modification will affect KE performance, but suffice it to say that the vast majority of planes - including exquisitely trimmed, megabucks pattern planes - usually have a bit of elevator and aileron coupling in KE flight.

I forget exactly how much and what direction, but my Phx extra, with the wing mod, still needs a bit of elevator and aileron to keep it going dead straight in KE, but it is so little that I haven't even done a mix for it. You can do a rud-to-elev mix (and rud-to-ail) mix and get most any plane to do a "no-right-hand" KE in dead calm conditions, but even then if there is a little wind you will still have to do a little correction. Also, left rudder KE and right rudder KE will almost always require a different mix, and it may also vary with throttle setting (airspeed), so sometimes it is best just to fly with sticks, and the plane will tell you what it needs.

I had an interesting experience late last season when another member of my local club wanted me to do KE mixes for a .60-sized P-51. With the low wing and high dihedral I figured the ailerons would require a ton of mix, but the elevator required a humongous amount of correction, so we started out with a simple rud-elev linear mix and I think we ended up with about 35-40% elevator-up mix - HUGE. Funny thing was, after doing that, we were shocked to discover it needed NO aileron mix, and it would do perfectly straight, no-right-hand KE's with left or right rudder at anything from mid-throttle on up. Quite amazing, actually!

The landing gear on this airplane might be made of lead. I have never seen a gear bend straight back against the wide direction of the gear leg. This one does. Our field is very short grass but a little rough. I am sure the bending is actually in the horizontal section between the bolts and the edge of the fuselage, but still, wow. My landings are fine. I do use spoilerons when the wind is blowing, but they are not violent at all. They just kill all the floating after flaring. Does anybody make a replacement landing gear that would fit in that area. I would prefer carbon or glass, but any good aluminum gear with the right alloy would work fine.

Go to [link=http://www.tntlandinggear.com/store/shop/Product_List_Gear.htm]THIS[/link] page and scroll down to Fliton and check out the LG for the Fliton Edge 540. I think that will work, with some minor modification.

They also carry Graphtech CF gear, but I used it before (on a Fliton Extra) and it delaminated after less than one season of flying, so I don't recommend it.

Yes, the stock LG sucks, bigtime.

EDIT: Also I just realized they also have it for the Extra, and I think this is the larger sized Extra (not the Mini) so that should be just the ticket. I think the Edge 540 gear are straight, not curved.

I bent mine a little on a dead stick landing that went long over the end of our field, into the bushes, but I was able to use my hands to force it bck into , almost the right position.

I remember looking into the Fliton Extra 60, Tower lists, as a replacement, I believe will fit after drilling new mounting holes.

Thanks cmoulder. I just left them a phone message and sent them an E-mail. I will report back when I hear something. I think we all could use a better landing gear.

Glad the 16x4W worked, Richlstubbz. My Saito 91 liked that prop for hover and climbout, but got bogged down to 8800rpm and wouldn't climb at all in KE> so watch for that.
As far as your hovering question, I think that 130mm (empty tank) should be fine- its within the build instructions 20mm range & I've flown like that. Just make sure you land quick if it gets squirrely as the tank runs down: the CG actually moves back during your flights as the tank empties. Figure ~.86 oz weight per oz of 10% nitro fuel or 0.90 oz wt. per oz of 20% fuel. So you can see that maybe 10 or more oz change in your tank will change the CG a lot, especially with the stock tank location. I guess that's why the discriminating flyers put the tank on CG!
A coupla tricks for the hover- step zero being that "waterskiing prop" you found- first try it nice and high near the end of the tank (tail heavier) it should settle in better than full tank performance.... second, I found that I was over controlling in hover, and did much better on low rates at "factory" throws. Each plane has its own unique characteristics as it tries to flop out of hover. Oh, one other thing with that rockin' ST90 you should be able to set the throttle to slight climb, and things stabilize a lot while you get the hang of what to do when. Then slowly use less and less throttle until (someday years from now if you are like me) you are eventually doing a tailslide!!!!

One other trick I noticed when Andy Jesky did a demo at our field a coupla years ago: he was blipping the throttle constantly (maybe 10% up and down from hover throttle) during his nose-up manouvers. I think that the little puffs of thrust helped the surfaces work better for control. But then, he has quick reactions because he's younger.... so this trick may help you better than it does ME!! I do find myself using this throttle trick on my foamie, but on the Phoenix Extra, not so much. My Saito isn't all that responsive on throttle, so I tend to pick a setting for hover and then chase it with the other controls.

Richlstubbz: I'd been flying with a Saito 91 4 stroke and a 16 x 4W APC with great hover/3D punchout.
I did not like the knife edge at standard 120-130mm cg per plans because it could barely hold and not climb in KE.
Then I tried a 15X6 Zinger and a 14x6 APC, still limited KE but hover/3D still OK. Then I tried a 14X7 APC and it fixed the KE performance.
Just a little extra prop blast made the difference. Still hovers very well, but with less punchout. Climbing in KE is important for 3D so I like the compromise.

Prop ________RPM ___Pitch Speed (theoretical from (pitch/12)a.k.a.feet per rev X rpm X 60 / 5280)
16x4W APC __8800 ___33.3 mph
15X6 Zinger _ 8700 __ 49.4 mph
14X6 APC ___ 9900 __ 56.2 mph
14X7 APC ___ 9100 __ 60.3 mph

I think that it is the pitch speed doing it. The 14X6 didn't load the engine enough so the 14X7 did the trick! I got that hint from an unofficial Saito page (http://saito-engines.info/prop_sizes.html) where the author suggested the hard to find 14X7 as the ultimate prop for a Saito 91.
Since your ST90 liked the 16x4W so much, it may also like the 14x7 if you can find one.... its a bit of an oddball, known as the Pattern prop.
Frankly, I expected good KE, but limited hover- but instead I got BOTH working well.

Definitely need some speed to KE because the fuse doesn't have a lot of side area.

With both .91FS and .91FX I use an APC 13x8 sport prop. But I don't do a lot of hovering.

Bob, could you re-post pics of this mod? I'm finally ready to finish putting mine together and want to do the mod. Thanks, Jim

There are some pics of the incidence mod [link=http://www.rcuniverse.com/forum/fb.asp?m=6743930]here[/link] from when I did it the first time.

First photo shows the slight elongation of the top of the rear wing bolt hole and the guide mark for the new wing position, and the second photo is of the little ply plate that will hold the wing bolt in its new position. It's easy to make the guide mark by installing the wings as usual in their stock configuration, laying a piece of 1/8" play flush with the fuse and then making the guide mark with a fine-tipped Sharpie. The change is so small that the front wing bolt hole is not affected.

Bob, I was xmas shopping for myself (hard to buy for cuz all my expensive tastes fly!) but whenI look these up they are for a 2 lb plane... do you think I need two or three of these laminated together for my 6-7 lb. plane? http://www.graphtechrcshop.com/produ...&categoryId=23
Or does Graphtech just beef them up a bit on request?
By the time you get the gear beefy enough, I am worried that I won't save any weight and will have spent $30 or more just to make a $139 plane look pretty....

I haven't checked the Graphtech offerings in a while mainly because I just don't think I would use them again for IC engine planes due to their tendency (verging on certainty!) to delaminate. I got the CF gear from Aeroworks for my 50cc Yak (looking very much like a Graphtech product) and - guess what?? - it delaminated within a couple dozen flights. There is a reason the vast majority of IMAC guys use aluminum LG.

Getting back to the gear for the Phx Extra, it could be that they no longer make the CF gear for the larger Fliton Extra 330 Freestyle, since that plane has been discontinued by Fliton. Bottom line, give them a call to clarify what they've got.

I am filling out a form that TnT Landing gear systems offers online. They will then have all of the dimensions of the gear that we have on our Extras. They will either fit that to an existing gear or offer to make the actual replacement. I don't know the dollars yet, but I will let everyone here know when I get the answers from them.

Thanks for that TNT update, Maynardrupp:

In the interest of weight savings.....while you are talking to them:
I see that TNT will use real 6061-T6 aircraft aluminum, T6 means that it is hardened.
In that case, the gear won't have to be as thick???!
All aluminum weighs about the same per cubic inch....so to save any weight, it would have to be thinner.

My guess is that the "substantial enough looking" gear with this ARF just suffers from being low grade aluminum that wasn't or can't be hardened.
All in all, I have found the gear that I got from Phoenix to be survivable, just needing to be straightened every 30 flights or so during my ~200 landings.
(I liiiiiike doing touch 'n' goes!!!) I'd imagine, based on many subjects about kit variations in this thread, that some of us got softer gear than others.
On top of that, some of us "plop" land more often than others. So the needs and desires of the group vary widely, just read a few posts!

PS: Manymost of "us" probably just want dimensionally identical gear in less sucky aluminum- but some (me for sure) would probably be interested in a thinner gauge aluminum at "today's" strength.
This gear weighs 6.5 oz "wheels, axles, collars & all" and 4.15 of that is the aluminum. If we lose just 25% of the thickness and use hard aluminum, thats an OUNCE!!
By contrast my Modeltech Magic (~4lb) has Gear that is taller and wider (a.ka.bigger) and weighs just 3.2 oz same Ø wheels and all. (That is made of brazed steel rod and is less pretty.)
I know the Magic has gear which is legendary for breaking but when a buddy made them out of decent steel and braze, they worked great.

Time to baste the Turkey- enjoy, y'all!

Bob, if I set the stab incidence to 0, do I need to mod the wing?

How's the vertical with a ST .90 with this bird? I have one with CH ignition which will be running on glow, looking for a home. The price is pretty decent.