New/Rebuilt Aerotech Phoenix Glider

Last year at Mid West Power my Phoenix Glider had a motor issue and caught on fire at lift off and continued to burn during the flight until the boom burned in two and the glider came crashing to the ground.

The fuselage and tail were completely consumed. The wing was damaged but repairable since it traveled several feet from the fire when it hit the ground. All radio gear was "flung" from the fuse when it hit and survived with no damage.

Last weekend I decided it was time to see what could be done with it. Here are the results. It seems this particular Phoenix actually did rise from the ashes.

My son is finishing up a 30% Sukhoi R/C Aircraft in the Red Bull theme and since I already had the graphics on the computer I thought a Red Bull Phoenix would be cool.

Other than adding the finishing stripes and two ounces of nose weight it's ready to fly.

The discussion on the "final flight" and photos of the burning Phoenix can be found here:
https://www.rocketryforum.com/showthread.php?t=26078&page=7

I thought the flames might be appropriate and they are standard on the Sukhoi


Yep. Back from the ashes....REALLY!!


Top view


Bottom view

Ooch! The photo series of the tail twisting around as it burned through was painful. Glad you were able to repair it, and the Red Bull theme looks great.

kj

Maybe the flames are a bad omen?!? Are you going to bring it to MWP 10? I enjoyed watching it fly, I think you were probably the one person that was getting some good use out of the constant wind!

Yep. Planning on bringing it and some other stuff as well. MWP 10 has been on my schedule since MWP 9!!

Nice rebuild! I just picked up one of these, still in the box.

Great job Joe!!!! The new scheme looks great! Can't wait to see it take to the skies again at MWP!

....must build my Phoenix!

-Eric-

Got the first flight on the "new" Phoenix on Saturday at the TORC launch in Ohio. Wanted to make Thunderstruck but just couldn't put the logistics together.

The flight was nominal. The takeoff/launch was downwind due to the range set up and wind direction. Being out of trim the altitude reached was only about three hundred feet and it seemed a little sluggish on elevator once the motor quit. I think it may be a bit nose heavy. Possibly a chance to get rid of a little weight !

I decided to build another one after finishing this one and printed out the pattern set. Apparently my math skills are suffering since this was supposed to be Phoenix no. 2 not Phoenix times two. Anyway this will turn out to be a Phoenix on steroids.
Wingspan 8 feet
Length a little over 6 feet.
power....54mm J90?


Pardon the messy shop but stuff just starts flying when I build..



That's a 36" metal straight edge on the one wing core


My rebuilt Phoenix on top of the "big 'un"

this is very cool. Do you have any guesses how much it will weigh?

I am hoping to come in around 6 pounds. Anything under 8 pounds will work fine.

The wings are now sheeted and aileron servos installed the total weight of all components is slightly over 4 pounds. There is a lot of shaping to do to the tail which will offset at least some of the covering weight.

Covering, two more servos, receiver, and pushrods (carbon fiber) and horns and associated hardware are all that is missing besides the battery.

The battery will likely be chosen for weight rather than capacity. The small glider needed a couple of ounces of nose weight and I expect this one to need weight as well. Might as well use something useful like a larger capacity battery rather than a chunk of lead.

Stay tuned.

I've flown a glider, albeit a delta winged one, on a J90 back in '95, and it got waaaay up there. Nearly lost it even on the old 700+ acre site we had then.

Glider was right around six pounds, and seven liftoff with motor, and it seemed to 'chug' its way up fine...neither too slow nor too fast...and that's about what you're looking for here.

Your Super Phoenix should do VERY nicely on that load, just don't burn the tail off! :y:

Thanks Mike!! Nice to have some kind of baseline.

I'm getting older and my eyesight is failing. I'm thinking of mounting binoculars on my head just in case. Much like night vision goggles

My son came over last week and took a look at it. He's big into R/C 3D flying. After looking it over he expressed an interest in building one too. He is going to LDRS with me this year. I'm thinking maybe a Giant Phoenix drag race!!

Joe -very cool! Who cut your wing cores? Is it just upscale or is it another profile? Please keep posting!! Thx!

I cut my own cores. I built a gravity controlled hot wire cutter that will let one person cut tapered cores. I need more friends.

The airfoil is pretty much an exact upscale. Just a little thicker. I've done a lot of upscaling on R/C models and things seem to work out pretty well that way. The leading edge is not as sharp in an attempt to slow it down slightly to make it easier to pick a landing spot.

I will post my progress.

Joe- oh you have friends, you just haven't advertised enuff! This make me want to dig out my last Phoenix and start to build. Unfortunately, my last R/C equipment had tubes :y: Mite be time to re-join the 20th century.... Color the sky, buddy!

Ah Yes, tubes. And Rubber band escapements. Push once for left, once again for neutral, once again for right, once again.....wiat a minue. Where was I?

The good old days. You can have them. Equipment is lighter, smaller, cheaper, and more reliable now than twenty or thirty years ago.

fyrwrxz,

Come on back, the water's fine!

Encouraging words my friend! Looks like it's time for the old dog to buy some new tricks. As soon as I can can figger out how to get my VCR to quit flashing.....:y:

I'm likin this thread.
Some folks out west were going to build a very big Phoenix years ago but don't know if they ever got it done.

Keep us posted....

I've been otherwise occupied and got distracted from the Super Phoenix, I like that name. Thanks Mike.

I have been working on launch equipment. We have a launch for 600 Boy Scouts coming up this Saturday. Doing the math, one every minute for 10 hours will do the trick. I hope things go well. At least the weather looks very promising.

Just to let you know I have sheeted the wing. No vacuum bagging for this one. Just 3M 77 spray adhesive. It worked for about twenty years on the other one and my vacuum pump will not run for some reason. The wing is joined as well. I wanted to use a wing tube but am running out of time and just went quick and dirty with plywood dihedral braces and a glass cloth reinforced center section.

The tail as well as the wing is bolted on with nylon bolts to alleviate some transportation problems. It will take a few more minutes to set up at the field but should resist hanger rash better and fit in my car. The launch tower is another question.

Photos to follow. Just haven't had time. I'll try to get some updated pictures in the next couple of days.

Oh, by the way, never build an eight foot wing in a seven foot basement.

Sorry for the delay. I just can't seem to get organized. I have been working a little at a time and keep thinking I need to get the camera out. But that's upstairs so I'll get it next time.......WRONG! Suddenly, there is nothing to take photos of other than the finished model.

Anyway, here are a few photos of the almost complete Super Phoenix. I still need to set up control throws and balance to the CG location. Hatch attachment will be with magnets and the switch will be inside out of the way.

First photo is of the Super and the standard Phoenix. Super Phoenix is just twice the size of the original.



Next we have a photo of the bottom of both planes in front of my gardening shed that really needs painting but my wife says it looks rustic that way. I love her.



Then the top. The Red Bull scheme comes from one of my son's airplane color schemes.



The last photo is of the bolt-on horizontal stabilizer and vertical. Unhook the two clevises (clevi?) from the control horns and take the two bolts out and the entire tail comes off for transportation. The Super Phoenix will accept hardware up to the Aerotech 54/852 case. The Aerotech J90 is the motor this was designed to use.



I hope to test fly this in two weeks at our local WVSOAR launch in southern Ohio and then on to LDRS!!

Final weight should be around 7 pounds. Maybe slightly more depending on the amount of weight needed to balance.

Joe,

The big one looks good! I have been thinking of doing that for a couple of years now, but just never got around to it. I had been thinking of setting it up for the AT I59WN, so not quite as hot as the J90W. That J is going to go pretty fast, ROUGHLY 100 m/s, and 600 to 700 meters. I would certainly start test flying on something milder, like maybe an I115 W, about half the altitude and 70 m/s, although a tiny bit higher acceleration.

I am slightly concerned about how the vertical tail is attached. It does not look like you have the vertical tied into the fuselage side, like the normal kit vertical was. That was a major part of the strength. And I would add some sort of corner bracing where the vertical glues to the plywood plate. If the vertical can flex side to side, its much more prone to flutter at high speed... NOT a good thing!

I dont know what you have for pushrods or servos, but the photos show the rudder linkage going into the inboard hole on the rudder horn. You really need very stiff linkages and good servos to handle 200+mph, and part of that is using the farthest out hole in the horn that you can manage. Then turn up the servo throw in the transmitter as high as it will go, and pick a hole on the servo arm that gives you the right throw. This will reduce the flexibility and slop of the linkage, and increase the flutter speed. Keep the mechanical throw of all the control surfaces pretty small (about the same angles as the kit says), since small throw really cuts the loads (half the throw is about 1/4 the servo load). And its worth using digital servos on this (less displacement under load, so less likely to flutter).

Bob Parks (Phoenix designer)

Hi Bob,

Thanks for your input. I have been flying your Phoenix since the early nineties and have used about every type of F and G motor there is. Particularly when there was a shortage of the R/C motors from Aerotech. I lost it in the fog one time and found it later that day in a neat little pile, have launched with ailerons reversed, and last year had the glider catch fire due to a motor cato and burn the tail off in flight. The photos are on in the MWP9 thread elsewhere on this forum.

I had intended to tie the vertical to the side with a bolt on plate to make it removable. During a build like this things are rather fluid and I forgot to do that. Thanks for the reminder. It really should be there.

I had looked at both the I59 and the I115 as likely candidates for the initial flights because I really don't know what to expect as far as altitude and speed. This plane is heavy but the design, as you know, is pretty clean.

I am using HiTec 5585's for elevator and rudder and HS5625's for ailerons. Pushrods are carbon fiber tubes with 4-40 ends the same as I used to use in my 1/5 scale T6 back in my giant scale racing days so no worries there.

Nice to hear from you and welcome to the forum. I will keep everyone posted on my progress.

Now I have to build a launcher.

Joe, that glider looks like a lot of fun..too bad you spared us the Build pics.. Your side by side comparison pics make up for it.

I hope this isn't redundant info, but Ed LeCroix (apogee/Aerotech) use to have a 4 rod tower launcher for his flights...maybe Bob Parks remembers it?
Anyway...have you fireproofed the underside of the tail by the motor flame at all? or is it just glass and paint?

If a J-90 is Ehhh can you fit a J-135 in there?

That four rod launcher is what we have used for years with the original. I am just going to scale it up and make a very sturdy base for it.

No fireproofing. The thrust (fire) is slanted away from the tail boom to allow the thrust line to pass close to the CG so the glider flies relatively straight rather than spinning around the CG. The only issue I had with fire was last year when a motor case failed and caught the boom. on fire. That one ended less than perfectly. We had no idea it was on fire until the tail dropped off. There were some trim changes happening during the flight that I didn’t understand however.

No glass and paint either. The entire plane is covered with Ultracote by Hangar Nine.

Bob has me worried that the J90 may be way too much motor for these old eyes. The reflexes are still pretty good but you have to be able to see it to fly it. The J135 would be way too long and probably add too much weight to the tail. I will be starting out with an I motor and go from there.

Joe- that is a spectacular bird! Absolutely beautiful lines (Thanks, Bob!) and a sterling finish. Any chance of you selling cores? At this size-almost makes me want to think of retract skids and spoilers! Thanks again for the posts-it's starting to stir the RCRG back up in me. Back from the ashes indeed!

It'll be fun finding the right motor for this. I'm not sure if the dual thrust 480ns is too much? I never liked the I161..too short a burn time.
I wish Gary would do several Blue thunder C-slot "I"s. Like the I-300 or I-435.
Then there are the Aerotech 426ns Soda cans ..the CTI C-Star 1 grain might be too much?:2:

JoeG said:

I had intended to tie the vertical to the side with a bolt on plate to make it removable. During a build like this things are rather fluid and I forgot to do that. Thanks for the reminder. It really should be there.

Click to expand...

Yeah, that should do it. Or put a plate on the inside with some blind nuts and bolt into that

I had looked at both the I59 and the I115 as likely candidates for the initial flights because I really don't know what to expect as far as altitude and speed. This plane is heavy but the design, as you know, is pretty clean.

Click to expand...

Just go run a simulation in any of the standard rocket programs. I use Open Rocket (free), but RocSim is also good. Go pick some normal rocket, 5 or 6" diameter and set the weight to match your Phoenix. It wont be perfect, but should be within 20% on altitude and probably closer than that for max speed.

I am using HiTec 5585's for elevator and rudder and HS5625's for ailerons. Pushrods are carbon fiber tubes with 4-40 ends the same as I used to use in my 1/5 scale T6 back in my giant scale racing days so no worries there.

Click to expand...

I would still move out on the rudder horn if its reasonably easy to do. Without actually analyzing the servo loads, those should be fine. Elevator is the most critical on boost, and the 5585 is really strong.

Good luck with it!

bob

fyrwrxz said:

Joe- that is a spectacular bird! Absolutely beautiful lines (Thanks, Bob!) and a sterling finish. Any chance of you selling cores? At this size-almost makes me want to think of retract skids and spoilers! Thanks again for the posts-it's starting to stir the RCRG back up in me. Back from the ashes indeed!

Click to expand...

Spoilers may have been a good idea. My son and I went to the R/C field for a test glide today. Sometimes in an upscale the incidence/decalage (tomato-tomahto) slips a little and I didn't want a terribly out of trim airplane going off the pad under power.

"We" launched it. I held the transmitter. Adam held it head high with both hands from a slight rise behind the runway, thundered ahead about five yards into the wind (very little), and then did the javelin toss thing, slightly nose down, using the empty motor casing as a push off.

A low wing is hard to launch by hand because the wing is in the way. An eight foot low wing is even worse. He did a fantastic job.

We both stood in awe as it flew 300 feet or more to kill about ten feet of altitude. It took no trim to fly straight and if I pulled on the elevator it wanted to climb. Controls were responsive but not overly sensitive. No bad tendencies, no falling off on a tip and I couldn't get it to stall. I credit Bob's design for the good flight characteristics. I'm just glad I was able to replicate it in its larger size.

Obviously the controls will be more sensitive when it is up to speed but I think it is going to be great. Can't wait to light that fire.

JoeG said:

A low wing is hard to launch by hand because the wing is in the way. An eight foot low wing is even worse. He did a fantastic job.

Click to expand...

Yeah, thats why I didn't suggest doing it in the kit instructions. If the person throwing it knows what they are doing and gets a good, clean throw, it works fine, but its way too easy to mess up and go splat really badly! (I heard of one case where the person was running, threw it way too much downwards then stepped on it..)

JoeG said:

We both stood in awe as it flew 300 feet or more to kill about ten feet of altitude.

Click to expand...

A good story on that.. back when I was doing the prototypes, a friend of mine was the soaring columnist for a major RC magazine. Lots of experience, had been on one of the US RC soaring teams, etc. So, he did a flight on a G12, no problem on the boost. Thermaled it a bit... then set up for what he thought was a reasonable landing. Well, the Phoenix went by at about knee height.. and kept going, and going and going.. What he thought was going to be a nice landing at his feet ended up overshooting by about 200 ft! ;-)

Anyway, glad it went well. I wasn't expecting any issues, but you don't know until you have done it!

I don't know if you do dual rates or anything for boost, but whatever works for you on the little one should work just fine on the big one. And I would do the same amount of down elevator (in degrees) for boost trim. Personally, I tend to use rather high rates for a first boost, just in case something is wrong. Once the trim is right, then I do lower rates to keep things smoother.

Bob

That was my experience with the original as well. Good boost, good control, a few aerobatics, set up for landing and land 200 to 300 feet past yourself. Of course someone always says, "I thought you had controls so you wouldn't have to walk so far."

The good part of that is (actually it is all good once you realize its capabilities) that due to the clean design you can fly this in any wind conditions that allow you to fly regular rockets. In a fifteen or twenty MPH wind you can just hover it down to the ground.

I do low rate and a little exponential on boost just to keep from jerking it around.

Well, those of you who were at LDRS know what happened to the Super Phoenix.

The Saturday flight was going fine until the vertical (you were right parky) let go. However it wasn't the point of attachment that was the weak link. Actually it was still glued on. The structural integrity of the fin/rudder assembly was the problem and it just ripped apart. Probably from flutter. I had used a built up structure to try to save weight in the tail. The I59 that flew it actually has a boost grain in it that causes the initial thrust to be around 170ns. Then it drops to the 60ns average. I think the extra boost at the beginning is what did us in.

Once the fin came off, the glider skewed (yawed) into the direction of flight which put too much force on the wing and it folded. I don't know if anyone got photos but the fuse stuck in the ground like a fence post. The wing and what was left of the fin fluttered back to the ground in pieces. You may see the flight in all its glory on tv since the Science Channel was following it.

The rest of the story is that we put out a plea for parts to repair it and fly it again before the end of LDRS XXXI. Within minutes, parts, offers of help, and well wishers began pouring in. Adam, my son, and instigator of the repair effort, made a trip to a Rochester hobby shop to gather the couple of remaining parts that were not available at the field.

After working in the hotel room on Sunday night we finished up the utilitarian repair around 11 pm. It wasn't pretty but it was deemed flyable.

We put it on the tower loaded with the I59 once again. I had a less aggressive I49 but I'm a slow learner. The boost was perfect. It topped out at the end of the boost and turned into one of the most gentle gliders I have ever flown. We had to cut out about a foot of wing center section that was damaged and it didn't even seem to miss it. I was able to do a roll and a couple of loops before landing. The landing was dead center in the field between the low power pads and the first high power pads. I think I even heard some applause.

This flight will not make the tv show. The producer said they had all they needed. Carnage and mayhem sells better than success. I do think Rockets magazine was filming so maybe they got it.

I would be interested in at least seeing any photos or video of either flight. Not sure when I will fly it again but I feel we did vindicate ourselves.

Thanks to all who helped repair, offered their ideas, parts, condolences, and support.

What a great community to be part of.