RE: HARMON ROCKET
 

Sweet thanks darock!

RE: HARMON ROCKET
 

Hi all,
having fitted the FA-80 to my Rocket I decided to reinforce the tail end, here is how I've done it, right or wrong! Very simply I drilled holes into the tail feathers at an angle (but not right through) and then cyanoed pieces of 2.5mm dia carbon rod into the holes. The rear end is now massively stiff for a very few grams of weight. Sorry about the poor photography.
Dave :^)

RE: HARMON ROCKET
 

hey all!
Dave :^)- that looks pretty fine to me i had to do a simmilar job to my funtana 40 when the carbon rods fell off n i couldnt be bothered to put them back on, i got alot of flutter, tis better with them. they dont need to be overly stuck on but just enough and they do the job really well.

i flew my friends on the other day i think he has a 57 in it, it wasnt uncontrolably fast but it wasnt slow, it flew realy well, like a low wing trainer realy, roll rate is slow. quite a well made plane aswell, i dont really like the undercarige leaning back though, do u often get noseovers?

isnt the FA 80 a lil bit big for that model?

well HAPPY FLYING ALL :D

RE: HARMON ROCKET
 

Hi PB,
I hope the carbon rods stay on OK, that was my reasoning behind fitting into holes. I had to flex the rods into the holes and they held themselves without the cyano. I'll keep an eye on them to see the cyano doesn't fail. The u\c apart from being bendy has no problem with being swept back. I'm going to get a "carbon copy" CCU016 swept carbon u\c to replace it. The ground handling is peachy not a hint of a noseover as the wheels are still well forward but not too far as to make ground looping a problem. The FA-80? hmmm? well it's slightly lighter than the FA-65 with which I could take off in 6ft but with a load more grunt. First outing with it tomorrow I hope! Should have unlimited vertical performance :^)
Dave :^)

RE: HARMON ROCKET
 

So I think this is going to be our next project. My brother wants
something that is a tail dragger and offers some good speed
and maneuverability with a symmetrical airfoil. Having seen
one of these fly with an older FX.61 on the business end, we have
chosen this one based on how well it performs.

I have a few key questions about the model.

1) Would a ST .61 ABC with a Slimline Pitts muffler be a good choice for this model or
would you opt for the FX.61 and why?

2) Would either of these motors need the entire head exposed or can
I just make a small hole for glow plug access? Yeah, I know...doubtful huh?

Having three servos in the back I would guess you need some weight up front
which is why (well that and price) I would want to go with the ST weighing in at
26.7 oz. w/stock muffler. The O.S. is 24.3 oz. w/stock muffler. The power output
seems to be equal on both motors but according to specs the ST runs at 500 rpm
higher while producing the same 1.9 hp.

3) What are the best quality standard servos to use that will shave some weight off the tail?
Standard digitals might be a bit much in weight penalties.

I really don't want to get into a pull-pull sytem for the rudder right away and I just want
to know what you all think about these motor choices. Nor do I want to go with
a stroker as I feel this model is better suited for a 2-stroke.

4) Has anything been improved like UC and hor. stab. on the newer models? If not
I will go with a flying wire system or a simple scrap pushrod type rigidizing which
I've seen a few of you do here.

Sorry for all of the questions, but any answer for either part will be greatly appreciated.

Thank you all in advance![8D]

RE: HARMON ROCKET
 

I flew mine for 8 or 9 months with an Evolution .455/ Bisson Pitts muffler. I placed the 1100mah battery on top of the tank and added about 3/4 oz. weight to the port side of the firewall. I chose the smaller engine to keep the cowl as intact as possible and to keep over all weight down.

Servos are all JR 537 located per manual. I discarded the supplied control rods and clevis' for 2-56 hdwe.

The pitts seems to limit the engine's performance and top rpm, but the plane has more than enough power and speed.

I cut the cowl underneath for the muffler; a hole was cut to reach the glow plug, high speed adjustment and cuts were made to clear throttle mechanism and carb. Nothing but the high speed and exhaust sticks out of the cowl.

I've just changed to the Evolution 52NX (still with a Pitts) since it dropped right in, and only had to enlarge cuts for the throttle mech. and carb. The new engine hauls it around nicely and pulls it vertically almost out of sight. I have a replacement cowl in case I decide to install a 4-stroke.

Unlike others, I've had no complaints with the soft aluminum landing gear or noticed any weakness in the tail surfaces--performs snaps and high speed manouvers, such as inside and outside loops without problems.

I've flown it 6-8 times a week since I finished it in January.

RE: HARMON ROCKET
 

Sportflyr,

These would be my thought on your questions regarding the Harmon Rocket:

1) I have an OS 61fx on mine, and I love it. I prop it with an APC 12x8, and it has speed like you wouldn't believe. The OS is extremely reliable, I have 4 of them.

2) I have a hole cutout for the muffler to protrude out, and a small hole to stick my igniter through. The cowling is so big on this plane, that is all you need. It looks very clean. I have thought about opening up more just to let the engine breath a little more.

3) I am using Futaba 3151 gidital servo's. They are cheap, and have plenty of power. I have my reciever battery way back near the tail, but I didn't have to add any wieght.

4) I am not sure if they have improved the landing gear and the strength of the tail section, but if you are going with a .61, I wouldn't take any chances. I added the supports to the tail feathers just like the pictures on this thread, and also some hanger 9 .60 sized landing gear. I had the sam problems descibed here with the gear, and I wanted to play it safe on the tail.

Hope this answers your questions. Good luck whatever route you choose.

Adam

RE: HARMON ROCKET
 

That'll do!!! Thanks guys!

I also love the 3151's and would love to go with them also
but thought that three of them on the tail might be a bit too
much.

Adam, are you also using the 3 servos on the tail or a pull-pull?

Looks like I'll be buying my first O.S. for this girl, I really
like the performance of these motors. A couple of guys
race Shoestrings at the field with this motor and Pitts mufflers
and they absolutely rock!

thanx again!

RE: HARMON ROCKET
 

sportflyr,

I am using three servo's in the factory spots. I still had to put the reciever battery near the tail to get it to balance without any wieght.

Adam

RE: HARMON ROCKET
 

Hi my dad,s got one of these rockets with an sc 61 fitted. At full throttle pulling out of a dive the left hand tial plane snapped. To fix this problem the film was cut off from under the tail plane ribs removed and solid balsa was shaped and fitted inside. The tail plain is now solid balsa wood. No flutters since it can now dive at full throttle and up to now pull out safely

RE: HARMON ROCKET
 

davy122, is your keyboard broken?

RE: HARMON ROCKET
 

no its not

RE: HARMON ROCKET
 

Hi dont get any nose overs but every time we land the landing gear just bends

RE: HARMON ROCKET
 

Thank you for editing your post, I can now read it without a translator. Welcome to the thread!

RE: HARMON ROCKET
 

I wonder if the problem with the horizontal stab is a scaled down version of compressibility, such as experienced by some fighters in high speed dives during WWII....[sm=idea.gif]

RE: HARMON ROCKET
 

hi my dad was flying his harmon on sunday and there was a glitch on the dive as he pulled out. when he laned it there was a big crack from the frunt of the tial about 2 cm long

RE: HARMON ROCKET
 

Davy,
perhaps it's my style of flying but I have had no problem with the tail on my HR3 (even before reinforcing the tail) With the FA-80GK in it's certainly no slouch either, although I don't point it flat out at the ground to see just how fast it will go. I prefer to fly in a much more scale manner including high G turns and have pulled turns so hard the plane has flicked out of the turn yet not broken anything.
Dave :^)

RE: HARMON ROCKET
 

Mine has been on the shelf for a while. I will have to get her out agin here soon. I don't push my plane real hard at high speed either. I love to to WOT flybys and then pull up sharply ito a 45 degree angle climb, do a stall turn and come down at full throttle and do it again. It is by far the fastest plane I have. I am not impressed with it's ground handling at all, and slow speed handing is a handful for me. I find it hard to keep it on our narrow runway. I think part of it is you have to land at a pretty good clip with the stall speed being so how. Mix that with the spring in the gear, and I usually get some bounce. It seems like I am all over the place on landing.

Anyone else having these problems? Any suggestions on technique to correct them? Still love the way it looks.

Adam

RE: HARMON ROCKET
 

No ground handling problems for me. I did have to learn to land under power to prevent bounces. The gear is soft and springy, which seems to help on the rougher of the two fields I fly from. The shorter and narrower field is smoother, but it's still easy to land and taxi. When the gear bends, and it has a couple of times, I just bend it back.

I estimate the plane has close to 200 flights, maybe more.

I've recently installed an Evolution .52 with an APC 11.5x7 prop. All servos are installed per the manual with no added ballast. It seems to be a great combo, but I have an extra uncut cowl and a Saito FA82a. I suspect I'll have to move the battery pack out of the nose to balance with the Saito.

Anyone have the EA RV-7 arf sold by Kondor? Getting the itch for that plane.

RE: HARMON ROCKET
 

i dont realy fly my dad plane often but when i do i fly it properly with a bit of distance

RE: HARMON ROCKET
 

Hope someone replys to this thread before it fizzles out. Has anyone tried to install an OS .46 or the new .55 in this ?. I simply cannot get my Enya to idle properly. Its a .51 and I've had enough of it. ANYONE ? MM.

RE: HARMON ROCKET
 

I recently installed an Evolution 52NX/ pitts muffler with a 12x6 MA Scimitar prop. Zips along just fine w/ plenty of vertical, too. I'd say the 46AX with an 11x7 might be comparable.

RE: HARMON ROCKET
 

Hi all
I flew my rocket today,and on take off about 6 feet off the runway it did a hard right ,wich I was no expecting ,and into the ground she goes. Not to bad little wing damage and a little to the fuse. Still dont know what happened, anyone have this problem?

RE: HARMON ROCKET
 

I had a similar problem with a 40 size Spitfire. I had inadvertantly reversed the ailerons in my radio while making adjustments to throttle throws.

Result: Spitfire that fit tidily in a trash bag.

RE: HARMON ROCKET
 

The only two things I can think of, is that you either tried to horse it off the ground two quick without enough speed, and it stalled, or perhaps a case of developmentally challenged thumbs. AKA: Dumb Thumbs
:D:D