Rob2007

I have recently finished CMPro's 50 size P-51 Mustang which I decided to test fly on Wednesday, the aircraft was powered by an OS 46 AX and finished, balanced etc as per the instructions.

The test flight was one the worst experiences I have had with an RC aircraft. Once the engine was properly set up and the aircraft range checked took it out onto the field for its maiden flight, and boy was I in for an extreme flight.

I opened the throttle for take off, gave it a bit of rudder to keep it on track and it left the ground and proceeded to enter a prop hanging position, I couldn't believe it, surely the C of G couldn't be so far out that the aircraft would want to go completely vertical. I couldn't seem to do much with it and it went over on to its back so I distinctively pushed down elevator for inverted flight, however I had full down elevator and it was sinking, this doesn't ring true if the aircraft was tail heavy. By this point the aircraft was coming towards me so I decided to shut the thottle and ditch.

The aircraft unfortunately did a cartwheel and has done quite alot of damage to the fibreglass fuselage.

Has anybody got any ideas as to what went wrong or has anybody had any similar experiences with CMPro's war birds.

Red B.

The most probable cause is a tail-heavy condition. Did you check the C.G. before flight?
Because you entered invert flight from a prop-hanging attitude you airspeed was probably
very low. If the wing was stalled down elevator would not help in maintaining altitude.

Too bad...

Ryan I.

My Feedback: (4)

Sounds to me like the CG was off and the plane was tail heavy. As was mentioned, you were probably flying too slow and were in a stall condition, making your control surfaces useless. Sorry about the rough first flight

bassfisher

My Feedback: (21)

My experience with CMP Models (I have the .50 size Zero) is that the CG in the instructions is way off. You can look up the CMP Zero thread. I believe in the main spar balance point system. Yours is no the first CMP Mustang that has gone it because of the factory CG being wrong. I saw one at my field go in from about 10' after take-off. I have learned with my Zero to also add balsa longerons inside the fuse to add strength. The Fuse on my Zero was too soft. The longerons didn't add that much extra weight.

Sturtz

My Feedback: (20)

Rob,,, they are not the best flying warbird CMP has to offer that's for sure. I cg'd mine slightly nose heavy the first few flights and found it to nose over on landings much worse than my other warbirds ever did. It has a bad stall tendency as well and if doing hammerheads you want to keep it nice and high. It's small and heavy. Not a good combo. I took it along to the field this summer and had a decent flight on it. "If you don't count the stalling." Flew a larger plane several flights and got back on the little P51 . It ground looped on me as well. Got it fixed and ready to go but I sure don't love this bird much. Saito .72 , 13x6 APC.

Hisham

Rob2007,

do u still remember where was ur CG located on this plane???
am assembling mine am just waiting for the incowl muffler to arrive.

Hisham

Rob2007

This plane was actually my first venture into scale and I have clearly made a poor choice, can anybody suggest a good flying warbird for next attempt.

Hisham, I balanced mine as the instructions which was 85mm back from the leading edge and 1800mm out from the centre of the wing, clearly this was way off, I would suggest you contact the manufacturer/distributor to see if this value has been revised.

maukaonyx

COOOOOOL pic. Looks very real till I enlarged the photo! Jon

Billville

World Models .46 and .60 size Mustangs fly very nice.

BTW, the yellow .46 size Mustang looks BAD in the advertisements on the Web, but in the air, looks the BEST by far, in my opinion.. It really stands out. The .60 size has flaps and flies bigger and is more forgiving.

This is assuming you are ready for a Warbird.

Bill

jeffk464

If you wait till december you can get the new top flight 60 arf mustang. It will be the best flying, best looking small mustang out by a long shot.

Norm Nestie

jmohn

The CMPs are a little heavier than other models. If you get the CG right they fly fine, just don't slow down too much on your approach. I have had several and like the bigger Hellcat and zero the best so far. The P40 was a fast and unforgiving plane and needed a lot of speed to land nicely. You may want to try a Hanger 9 or Top Flight P51 as they are lighter and have more wing. As far as scale goes the CMPs are hard to beat!

Sorry about your loss! My P40 burned up in flight

SCALECRAFT

My Feedback: (13)

Hi

If you have the CMP 54" span one, I have a Magnum 52 in mine with around a four ounce brass prop nut . With my cg location, its a very forgiving and docile version of the P-51D.

SCALECRAFT

My Feedback: (13)

A pic of my Cg location. Retracts retracted and model inverted. No fuel.

wdrosa

I agree with you that the cg is off. I have purchased 2 of the same aircraft. The first one was a nightmare in flite. The second one was no different. I purchased mine from Raiden tech. When I called to let them know that I was dissapointed with this product, they told me that I was the first one to complain about this P-51 50. They told me that they would send me another one after I ship the recked one back to them. So far no new mustang. I geuss if they ever send me a new one I will have a very nice scale static display. Sorry about your bad luck. I guess we should have researched this plane better.

Larry S

My Feedback: (6)

Sorry to see someone lose a plane but like others, I will bet the CG was way off. I had a CMP 50 Corsair and I balanced it just as the directions said and what a handfull it was to fly. I got it to fly and landed it alright but off to the shop. I moved the CG almost, if I remember right, a full inch forward then what the plans had said it should be and tried it again. What a difference that made and it turned out to be one of the best warbirds I ever flew until the day my received battery shorted out and end of plane. I have an idea your P 51 had the same problem.
Larry

Oosiksmith

My Feedback: (1)

I have their P-51 140, 71.5 inch wingspan version and haven't flown it yet; the instructions that came with it didn't give the CG or the control throws. To anyone who has flown that plane successfully, what was the CG and throws you used?

edmoor

My Feedback: (1)

cmp arf's.....dont trust anything they say about the center of gravity on any plane.....they are way off course here. my 182 skylane was very tail heavy.....my p-51 mustang was very nose heavy......i always revert to the old rule.....30% of the wing chord will get you flying fine....them cmp planes are way off. i cant understand their way of thinking here to publish this info. in the kits. i contacted them 3 times on my 182.....about it....i never heard anything back....i contacted nitro models....never heard anything back....they got my money....i guess thats all they care about. this is just my 2 cents worth here. and also....them fiberglass pushrods with them itty bitty set screws.....better epoxy them in place......they WILL VIBTRATE LOOSE. i epoxied even all my wires into them tubes....during an engine break in....i had all of them set screws come out....and i even used loktite on them....the major one was the elevator pushrods....they were all gone.....rattling around in the bottom of my fuse. pay attention here!!!!

bigtim

My Feedback: (13)

Hangar-9 Mustangs fly well and have a good slow fly attitude,with all thats been said about CMP planes they should put a warning,don't try to fly this thing following the instructions provided.

KentuckyColonel

Having lost my WillHobby FW 190 on her maiden last Tuesday, I feel your pain! I had a CMP 50 size P-40 and she went in on her third flight. I know of nobdy who has had any success with a CMP 50 size warbird. I'm sure they are out there.

Brad330l

My Feedback: (1)

Do a search in this forum and there is a lot of info and sad stories about this particular model.

Sorry for your loss. Be comforted to know you are not alone.

Brad

Larry S

My Feedback: (6)

Sorry to burst your bubble but I had a 50 size CMP Corsair that flew great once the CG was figured out. Lost it due to bad battery pack.
Emoore: I used the glass rods but made up my own ends. If someone builds this plane according to the directions using the hardware that comes with it, you'll have problems. I had to take several extra steps when assembling mine but everything worked good. One thing that bugged me was the placement of the machine guns, you think they could at least get that right.
Larry

jeffk464

I had the 50 sized p47 and it also flew like a turd, but once it was balanced it was flyable.

edmoor

My Feedback: (1)

what exactly is the proper method of balancing one of these?....upside down makes no sense to me.....yet....in the up right attitude,,,,,i cant get it find a point. i flip it over....the whole scenario changes. im a die hard high winger....this is my second low winger....i never have had so much trouble as with this cmp p-51. i cant believe what they state on the directions that came with this plane about the location. i even have a small .40 in mine. maybe im confused here.....in the upright flying attitude....on the stand....mine was very nose heavy. i added 1.5 oz. to the tail. i flip the plane upside down....it shows it being tail heavy,.im lost here on this subject.

Larry S

My Feedback: (6)

I used a Great Planes C.G. Machine and balanced my Corsair upside down. I just know from experience from having one other CMP Corsair that it was tail heavy in flight yet I had it balanced exactly where the directions said. On the second one, I moved the CG forward which meant I had to add nose weight but very little if I can remember. Reason, when I built the second Corsair, I went with a 60 size motor, glassed the complete inside of the cowl and added some 1/16 ply to the back of the dummy engine. I had moved all my servos as far forward as possible and also move the battery as far forward. All this added weight but usuable weight. I hate adding lead if I have to. NOW, this is a suggestion only, if your P 51 were mine, I reinforce the front of it then move the CG at least 1/2 to 3/4 of an inch forward of the suggestive CG, making it tail heavy on the stand. Then add weight to the nose, if needed, to balance it. IF you can find someone who has this plane and has no problems flying it, that would be better for getting the correct CG.
I won't claim to be an expert on all CMP planes but I do know the 50 size Corsair is a very nice plane when set up right. As for the directions you get, best thing to do is throw them out and use building experience. If you don't have building experience I'm afraid you will have problems. Also I would suggest unless you have experience flying warbirds, have someone who is experienced test fly the plane for you. IF it is still tailheavy, he will have more experience getting it back in one piece.
Larry