By George, I think you got it! Before he was a Rocket driver, he did pizza delivery, and now he's mad with mozzarella.....[8D]

i`m gonner sack my pilot.......i dont think he is a very good flyer....think i will put bart simpson inside as i think the plane suits his personality.i.e a little unpredictable!!!!!

LOL!! I have the guy in a red suit like you boatman. He looks quite a bit like Santa Claus!!! I am of the opinion that ole Sandy Klass should keep to the sleigh and not the Harmon Rocket!!! So, a quick fix to me was tint the canopy!!!! Very dark I might add.

BTW. I got the engine trouble figured out yesterday at the field. it was just the low end mixture. I re-set to the factory settings and leaned it out just a touch. Runs like a champ!!! Unfortunatly it was quite breezy so I didn't even attemp to get the Rocket into the air. One guy at the field crashed his plane when the wind died on approach and his plane fell out of the sky... oops, messed up his gear pretty good.I might be able to get out on Wed. afternoon for a few flights. Depends on the weather. (kinda a given this time of year!!)

.It dont look like i will be able to fly for a couple of weeks because of private comittments....by then i think the winter will be truly set in here in england so as i can only fly weekends my windows for flying will be few....boooooooooooo. i am toying with the idea of putting a smoke system in the rocket as lots of room but i am wondering if this will add too much wait as i already have a .70 4 stroke in it and my short experiance with the rocket is it is a bit of a brick..........any suggestions guys? i also was wondering if i could get another set of wings weather i could make it into a bi plane as i really do think this plane could do with some more wing area.........feedback would be interesting folks...

I flew my Rocket for the first time yesterday and thought I'd post some results and observations here to add to the knowledgebase -- you guys have been most helpful so I thought you might be interested. First off, from this forum I've gleaned that there are two issues with this plane: an aft CG tendency, and weak landing gear legs. My experience matches this exactly, thanks guys.

I built my plane stock with all the servos in the standard locations. It has an O.S. 46AX with a Slimline muffler, which I believe is a bit lighter than the stock version, and a Graupner 11x6 prop. I debated about locating the rudder servo forward and installing a pull-pull system to move the cg forward a bit but opted not to just because I didn't want to take the time to engineer it. Getting the CG in the specified envelope required 2-3 ounces of lead up front. Control throws were all set to the specs in the manual for standard rate, expo was programmed on aileron and elevator channels, and flaperons were programmed on a switch.

In terms of prep, I used the RV-4 in AddOn Four of my G3 simulator to practice. I am also a regular pilot as well and have built and flown (400 hours) an RV-8 (www.rv-8.com) so I am familiar with these aircraft and their characteristics. Of course a Harmon Rocket is just a modified RV-4 for those of you who may not know. The sim RV-4 has similar characteristics to the real plane, but some differences as well. For one, as you reduce power in the sim the plane pitches up noticeably... the real plane doesn't to that.

After checking everything over multiple times I launched my first flight. Surprisingly everything went well and it flew similarly to the sim, though with a few differences. Actually it flies better than the sim! I'm pleased to report that the control settings were right on and I ended up changing nothing, even my guess at flaperon settings were right on. BTW, they do reduce stall speeds, and thus approach speeds, noticeably, I'd say be a third, so if your radio provides that feature I'd recommend you try it. For those unfamiliar with it, you put your right aileron on the aileron channel, then your left aileron on the aux 1 (flaps) channel.

In all I made four flights with no mishaps. Overall I'm very pleased with the way this bird flies. While it is definitely not a beginner's plane, it flies slowly enough to be mananable in the pattern, yet speeds up nicely. Aerobatics are very crisp when you pick up the pace, and just like a real plane they get a bit sloppy if you're too slow. The 46AX provides plenty of power, which I was a bit concerned about. I can get 12,500 rpm on the ground, do I have the right prop? It is not as forgiving in the stall as many rc-specific designs, it will drop a tip, usually to the right, but is actually very scale-like in this respect. In all it is just what I was looking for in it's flying qualities. I am an intermediate RC pilot at best and this is good fit... will remain challenging for some time yet satisfying after I have moved up the learning curve.

No question the landing gear is weak. Just as others have reported, each landing splays it out a bit further so you need to bend it back a bit after each flight. I will make some new legs out of a more suitable material soon. The stock legs are very low grade aluminum, definitely not up to the task.

Yet to do: move the rudder servo forward to the main tray and install the pull-pull system, and make some new landing gear legs. The thing is just beautiful whether on the ground or doing a low pass. I left the wheel pants off knowing I was going to replace the landing gear. No question I'll put them on once that's done, they definitely enhance the appearance.

Hope this was helpful!

Cheers,
Randy

Well Randy ! look's like you joined the club !. Make your new gear [ or order it from Horizon ] more to scale in looks. The pull-pull is no problem, use a Sullivan kit. Tinted canopy looks a lot better, but thats up to you. I wish Leo would not have had all the problems with his but it looks like he might OK now. seeya, MM

RandyRocket,

I have this ARF not yet built, and I appreciate your feedback much.
I'm a bit worried about landing part of this plane, could u please describe how the landing was ?
And, could u compare to other planes, in terms of landing ?
Thanks.

Jake.

Jake,
In flying real aircraft one of the old adages is "good landings are just the end of good approaches". I think that's true of any plane, including RCs. The way I've adapted to RC is to make several practice approaches where you get set up with the appropriate rate of descent and the appropriate airspeed using whatever trim and throttle you need to get the right combo for a "stabilized approach". The plane should almost fly itself onto the ground if you've set it up correctly. If can't get your approach stabilized, and you wont' the first few times, then just keep going around until you get one you like. Start this process at maybe 5 minutes into your flight so you have plenty of time time and fuel to make a dozen approaches if need be. If you get one where you're on glidepath then just continue on down and at around a foot off the runway GENTLY pull back whatever throttle you have on and GENTLY pull back on the elevator and it will mush (stall) onto the runway. This should work with any conventional aircraft and the RC Rocket is no exception. If your radio cannot facilitate the flaperon setup then it will just be a little faster. In that case use a bit flatter glideslope.

Most of the RC planes I've flown so far, mostly trainers and such, have very benign stall habits where they don't break cleanly and don't drop one wing or the other. The Rocket does stall more abruptly, and with a wing dip. Therefore you'll want to be careful to not get it too slow and stall it on approach. Not a problem though if you do your practice stalls up high and get used to the signs, which you should definitely do. Then just manage your airspeed on approach and you'll be fine. I dont' know what you've been flying, but the Rocket lands faster than the trainers and slower than some other planes I've seen. You can do it, just get the approach right. Then on rollout, keep your left thumb on the rudder and be ready to correct any directional deviations... a lot of guys forget this part and end up hitting a fence -- they get it on the ground and then relax and quite paying attention.

Best,
Randy

Thank you very much for your advice, RocketRandy.

RocketRandy,
On your flaperons, how much have you got the throw set to? I don't remember how much I have on mine now, but I quit using them after a few attempts. Mine wouldn't slow down enough to make the adverse yaw worth while. Since then, however, I think I have trimmed enough wood away to lighten the airframe a bit, and I can now make the Rocket flair a little on landing. You are dead on, you have to fly this to the ground, for me a couple of clicks of throttle keeps the speed up to the point where the wings don't rock before touchdown. I don't know what lightening the fuselage would have to do with it entirely, but it now does a pretty decent roll, before, it would sometimes almost "hang" once it got inverted, and not even go over. I really think mine came with heavy wood. I want to try the flaperons again, but I have to wait for this fall monsoon to be over with. I have had one opportunity to fly in about a month, and it was fairly windy. Report back after you have had a chance to fly in gusts 10 - 15 mph. Watch the crosswinds on take off and landing, this one will wingover rapidly, or at least more quickly than I would have expected. This thing flies much better since I have trimmed some wood off the inside, and went back to the stock size tank, lightening it up. Wish I could do the same to the wing, without messing up the covering.

When you go to replace the landing gear, try to keep the axles at the same distance from the leading edge, or you will have poor handling on the ground. I replaced the stock rear tire with a larger diameter one, and this seems to help keep it straighter in the grass / cultivated weeds of my runway.

My flaperons are set to about 80% of the down aileron travel. I guessed that the flaps would pitch it down and programmed in a touch of up elevator to go with it and it ended up just right, the approach speed when I hit the landing switch is almost perfect. With the flaps set this way when I move the ailerons the one going down bottoms out if I am using much stick, no problem with that though. Seems to work well, and there is no question that it slows it down, I'd say by a third.

Thanks for the other advice, I'll definitely watch the crosswinds. I've flown my RV-8, as well as quite a few other full scale planes, in crosswinds and it's just a matter of keeping the upwind wing down a bit and keeping the bird straight with a bit of opposite rudder. Any new gear legs I put on would keep the same geometry. I was considering making them just a bit longer though, maybe .75".

Where the crosswind got me was right before the point the plane would be getting airborn. It was light on the wheels, but not off them yet. I also wasn't at full throttle at that point. I like to bring the throttle up as the plane increases speed to make the rudder / tailwheel transition smooth to avoid the tendency to turn before the rudder becomes effective.

I will see where the flaps go to on mine, now that I have lightened it up, it may respond better to them. Before, while I was testing them, the use of almost any aileron when the flaps were deployed would result in a kind of pivot or pitch off to the side. Flaperons on my Tiger 60 work quite well, with zero surprises. I wish everything flew as predictably.

Hi guys I've also got a Harmon Rocket, has any one thought of using a landing gear from a Great Planes RV 4 kit?

E Hagen

CLOSE !!......... But no "cigar". Try it anyway. MM

Well I finally got my Rocket back into the air today. Was a great day for flying, very little breeze and sunny. Quite a rare thing around here. My first flight was very good although my take off left quite a bit to be desired! The grass runway was very wet from a heavy rain so the grass was very heavy. The little wheels on the plane made it hard to get going. Once I got it going it, lifted off too soon and I dropped it down for one big bounce...bent landing gear!! Oh well I bent it back so it is all right for now.

I found the plane very fast. I really enjoyed flying it but I started to get engine troubles again. I am wondering how an engine acts that is getting too hot. It seems to load up at 1/2 throttle starts to smoke a bit then after full throttle for 10-15 seconds it clears out and really flys great untill I back off the throttle again. There was a guy at the field trying to help me get it tuned up but I think he had a harder time tryng to figure it out than I did!!! Oh well at least he tried.

I ended up getting 4 6-10 min flights out of it before leaving for the day. Any ideas on if it is a cooling issue or just tuning thing.
Thanks, J

I found that I had to switch to a hotter A3 plug, mine just wouldn't tune with the cylinder horizontal. You couldn't get past half throttle, and it would load up and die. I ended up pulling the motor and putting it in a different plane, mounted vertically, and readjusted the needles, and it ran fine. It took about 3 - 5 min. to get it tuned. Once put back in the Rocket, it would start, and run up to about half throttle, and die. Once I switched to the A3 plug, it runs fine.

Thanks Bingo...that sounds very similar to what is going on with my plane. On the last plane it was vertical and ran flawlessly. So it must be either the plug or the cowl. I will try a hotter plug before I cut the cowel any more. I did have to change a plug at the field but I think it is a A8??? Not totally sure on that but it didnt help really anything. I will let you know how it turns out. I hope to fly next wed. again.

Leo, this is great !. I never thought a "little-bitty" ARF like this would have run a thread this long. I'm impressed. MM

I flew mine yeaterday -equipped with a .61 Evolution -on a 11x7 prop. 6.5 lbs
I put the cg quite forward -at about 20 % -and the plane is very predictable on all flight/landing characteristics
Lots of throws on all surrfaces .
It is not a 3D or pattern plane but easily does all the looping rolling stuff.
It does need to be landed, carrying power -but no tendency to do any thing funny.
The recommended cg is quite far aft for this type model.

Heavythumbs,
I think you need to lean out your idle mixture a bit. The symptoms you describe are exactly what my manual (O.S. 46AX) describes, plus it just makes intuitive sense.

BTW, I'm getting a light/part throttle surging which I think is the opposite problem. I will adjust my idle mixture screw out just a bit and see if that solves it.

Hi
I have a questrion about elevator servos directions in the manual.
If I follow the manual the elevators will move like ailerons, one side moves opposite way of the other side.
I know one way to work around but one control wire will be longer than the other which may make different range of movement of elevators.
How did u guys do it ? I don't have servo reverser.
Thanks.

Hi
I have been wanting one of these planes, think they look pretty cool.
My question is with all the balancing problems and having to move servos around
is it really necessary to have two servos on the elevators?
just a thought

Regarding the two elevator servos, I bought an MPI (Maxx Products?) servo reverser at my LHS for $8.99, works perfectly. Regarding balance, after all is said and done I put all my servos in the standard locations and then bought a Great Planes 2 oz. prop nut weight and the balance came out perfect, no other weights needed. This is with an O.S. 46AX and Slimline muffler, a fairly light power train.

The only real issue/problem I see with this plane is that the landing gear is made of really low grade aluminum and is simply too weak. If you're willing to get creative with making or adapting another set then it's a very straightforward plane to build. On balance I love it... very scale in the way it flies, and challenging enough to fly without being overly difficult, and I'm a fairly low time RC pilot.

RocketRandy

Hi All,
This is a great forum to read about this plane. I just got one about a week ago. For the CG concerns I was planning on joining the two elevators together with a 1/8" steel rod the same as my SIG Somethin Extra is and use only one servo. Any thoughts? I noticed a few folks tinted the canopy and was wondering how to do this. Do you remove the canopy. Can you only tint it somewhat? Also, does the firewall area need to be fuelproofed. I'm thinking of using an OS 46AX or maybe an OS 50SX. I plan to take the advise and inmprove the landing gear.

Keith

Keith,
One servo would certainly be able to drive both elevators, but you'll need to penetrate or notch the rudder to make room for the rod to go across. I tinted my canopy also: I cut the head & shoulders off the man (to save weight) and simply sprayed the inside of the canopy with Krylon black paint. Clean the inside surface with alcohol first and it will work just fine. I also took some 15 minute epoxy, thinned it a bit with denatured alcohol, and painted it all around the firewall forward area to fuelproof it exactly as you are considering... good idea.
Be sure and post your solution to the landing gear, I'm sure the others would appreciate it.