Well I took my brand new Radian Pro out for it's maiden flight this morning. I had gone over everything that I could think of and did my checks pre flight. Had a nice field of alfalfa about 6 inches tall and a gentle breeze, a bit of fog yet but I wasn't planning on getting too carried away on my first flight.
Gave it about 3/4 throttle and threw it up and it took off great .... flew about 20 yards in a shallow climb, rolled over to the right and went nose down right into the ground. Did a fair amount of damage to the front cockpit .... nothing that a little glue and TLC probably can't fix. Been evaluating trying to figure what went wrong. Noticed that the screws that hold the wings on had moved .... is it possible that the screws weren't holding , or did it hit that hard? Left wing aileron arm came unhooked in the crash ... looks like the little ring keeper failed with the impact, it was in place on take off. I believe that the cause was my C G ... it was not as perfect as I would have liked, it was off about an inch... felt pretty good though. This is supposedly an easy bird to fly and launch but something wasn't right .... unfortunately I don't know what that something is ... yet. It did not seem to respond to commands to climb or turn which was puzzling and I gotta admit .... it is hard to watch something like that. I love that plane and it took me a long time to pull the trigger and buy it cause I am pretty careful with money. I wish I had someone to take me under his wing and help me evaluate ... feel kind of all alone and not sure what to do next. HELP?
Replies
Just an update to you all. I finally found an R C instructor in my home town. Kind of funny how it worked out. I had the Radian Pro and 2 other nice planes and a lot of gear that I had bought from a guy who no longer flies. I gave up finding someone to teach me and posted them for sale on Craigs list and a young man told me if I wanted to learn to fly to show up at the field and gave me the name of the instructor. He is a great elderly gentleman who gives his time to the club helping others learn and a host of other things he does for free. I have now solo'd and have several other planes and my son is now a pilot. You were right to give me encouragement, but more than anything I want to let everyone know that sharing your knowledge is very important and I intend to help others as my mentor has. Your knowledge is very valuable for those of us who are struggling to learn and we need lots of help. So don't be afraid to help others at the field where you fly .... it is important and appreciated. Giving of your time freely advances the sport .... and it is a fantastic sport and hobby.
Now to teach my grandchildren when they get a little older.
Hang in there! I have splattered a whole fleet of craft in my few years flying. I think you feel miserable right now and that is to be expected. Give it a couple of weeks and the "sting" will lessen then you'll start trying to figure out what happened. As has been mentioned before, if you can get an experienced pilot to help you that will be best. They will know CG, range testing, et.al. He may want to try an fly it first to verify it. Of course that can stress a friendship in the event of a crash. I know it happened to me. You flying on a buddy-box with an experience person on the main is an excellent way to learn. If you don't have a pilot to learn from then if you can get a simulator, that can help a whole bunch. Good luck, take a break, come back with vengeance!
NO need to be discouraged! Until you've toasted about 3 dozen planes, you have not seen many of the things that can go wrong! The difficult thing is having the guts to learn to fly.
1. get the basics very close to right before you launch
CG about 1/3 to 1/5 back from leading edge (if the wing chord is 9 inches, then 3 to 2 inches back...)
range test your radio
make sure that wings and tail parts are firmly attached
have all your batteries fully charged (a little $5 volt meter is great to verify cell voltage is > 4.0 for LiPos)
test all control surfaces, to make sure that they are going in the right direction (pretend to fly the plane on the ground, and verify that ailerons and elevator and rudder are moving in the correct direction, when you move the transmitter sticks)
2. reduce all the other risks possible
choose a no wind day
choose a nice grassy field
keep away from flying into the sun
have someone else toss the plane (keep your hands on the controls)
have a good flier fly and trim the plane for you.
choose a time when there is no crowd watching (this is a bad distraction)
just before you launch, remind yourself that the worst that could happen is that you completely auger the plane,
and in that case, you are sharing in the experience that the best RC pilots have come to appreciate.
3. when something goes wrong, think about it, identify the error (if there was one), take notes, and don't repeat it.
Don't get paranoid. You're doing something that most people don't have the guts to try.
4. You know that you can build your own foamy planes with blue insulation foam from Lowes? There are plans on the web. Build 3 of the same model, and try different CGs.
5. If you destroy your Radian, and can't afford another, there may be ten guys out in RC land who would be willing to mail you one of their old beater trainers.
Stephen from Tucson
I agree with what has been said. CG is critical and should NEVER be aft of the mark unless you are a very experienced 3D aerobatic pilot, then you may want it a bit back but otherwise that only gives you difficulties.
What I think may have happened here is that you had the ailerons reversed. The description of the flight fits that error well. The plane starts to lean, you try tocorrect but the ailerons are reversed so the roll increases and ... bang. Most experienced RC flyers have a habit of checking the control surface movement before every (!) take-off, also to check for this setup error, which even experienced builders can make. Always move all surfaces before flight and see if they move freely and in the right direction. Control travel can be reversed by a setting in most transmitters and sometimes (I did this the other day) you forget to select the correct program for the model.
Do I understand correctly that you are a beginner pilot?
Another advice I give all beginners is to acquire an RC simulator and train to your wits end in it. These range from almost free ones like the FMS to expensive masterpieces, which the champions use to hone their skills. They alwasy save you money in the end. Even the simplest ones help you to learn how to fly. One of the first things to work into your spinal reflexes is to fly with ailerons when the plane is headed towards you. When you get that right without having to think, you are a long way towards being a good pilot.
I strongly support the advice to join a local RC club. The lads there usually love to help newcomers. If you don´t find a kindhearted mentor there, that club has problems.
I also want to remind that every beginner gets thouroughly discouraged at one point, you had yours a bit too early.
Keep the steam up, you will enjoy flying.
The R Pro is a sailplane so you should have no problem finding the right cg by hand launching. Still, other thoughtful comments express concerns about the attitude at crash. Let's review these items of the crash trajectory as you prepare for flight.
High aspect wings are subject to accelerated tip stall because the angle of attack tends to be higher at the raised tip even in a mild turn from purely geometrical reasons. The sudden wing drop and roll could be a result of a tip stall due to a slight left yaw disturbance and followed by sideslip/spiral entry.
The lack of climb rate with the throttle advanceded indicates that the plane was lugging on the backside of the power curve (too high an angle of attack-which is consistent with a tail heavy cg.) and headed for a stall.
With the throttle advanced, and a little left rudder in to compensate for prop effects, the right wing has a slightly higher angle of attack than the left and would be the first one to stall .
Don't give up. Make the plane glide smoothly on a power off hand launch by trial and error placement of the cg, and it should it climb out like a champion when you when you "go with throttle up"..
Mike
Craig, after reading all the other responses and adding my 2 cents worth I would say that it could not have been your CG, as the other said, it would have been uncontrollable from the start. Check your radio equipment and battery connections, sounds more like a loss of power or a possible interference which could have caused an aileron glitch.
Not experienced enough to take you under my wing but will pass along what I learned fom the best pilot in the St Louis RC Flying Assoc.
Chris is right - cg is critical and I have many crashes to prove it. JH took me in hand and gave me a feel for where to put my fingers under the wings. From there I learned to do power off hand launches. For the Easy Star, grip well ahead of the cg/ and launch horizontally, any upward launch and the wing will stall. Typically the 4 planes I have built were tail heavy, and the ship will drop so start from a kneeling position to minimize damage. Add lead weight as far forward as possible and try again. Car Quest sells adhesive backed lead strips about15mm wide and 3mm thick used to balance car wheels. Keep adding weight in small increments until a true ,if short , glide occurs. Then add more weight and launch from a standing position. After several iterations the magic moment came and the Star soared like a bird. I walked off the distance and made a crude estimate of a glide ratio between 7:1 and 10:1. It has easily soared in thermals. The manufacturer says set the cg at 78mm back of datum. The hand launch test was best at 66mm back of datum. Go figure. PS The hand launch glides will also reveal misalinged surfaces and lateral unbalance probles if any. Good luck The Star weighs 30oz. It is not possible to hand launch a 30lb plane if that is what you fly!
Mike Cowan
Hi there sorry to hear about your crash.
Did the plane pitch hard up before it rolled over. How fast was the plane travelling. I have seen enough planes at our club field with the cg too far back and normally they will pitch up hard.
It kinda sounds to me like a tip stall or an aileron glitch..... I understand what the other guys are saying but the way you described the take off.
"Gave it about 3/4 throttle and threw it up and it took off great .... flew about 20 yards in a shallow climb, rolled over to the right and went nose down right into the ground"
Doesn't sound to me like CG error. I would go back through your radio have a check... do a range check at half power...
Don't get discouraged.......
One of the biggest factors in successfully (and relatively cheaply) learning how to fly any R/C model is having someone experienced get you off on the right foot and shepherd you through the learning process. One of the best ways to do this is to hook up with the local model flying club - provided there is one. While they may not understand or even care what your end goal is, usually at the very least they will bend over backwards to help a newcomer get started, and provide him/her with the foundational skills to get a model off and back on the ground in one piece. Your mileage may vary, but this has been my experience over the last 40 years.
If you have a local hobby shop (LHS), they should be able to point you in the right direction.
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