Dreamer
07-21-2008, 10:24 AM
#1
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Dreamer
Hi,
A couple of weeks ago I finished this kit. I enjoyed a lot building it, no problem at all.
As this is my first biplane I hesitated a little bit before the first fly but than I flipped the propeller and "Let´s go ..."
I am experienced pilot (3D , pattern), but I was really busy to fly this one:
During the take off it moves on runway as on rails. Airborne: it gains altitude smoothly. When I try to make the first turn, at the beginning everything goes well, but suddenly it falls on wing. I was able to gain speed and level it, but from that moment I was much more tense. I tryed to land it at relatively high speed (just estimation, but it seems no coreect) but about 20 m before the runway the plane did not react to elevator and landed softly by itself.
The second fly was a little bit better: I added exponential to ailerons and throw to elevator. The take off was again very easy. I made all turns extremelly carefully to not repeat the same error.
I went for landing at much higher speed that with my pattern plane. The result was that I needed a lot of runway, but once it touched land it was again "as on rails".
CG is accoding to plans.
Is this behaviour normal for biplanes / Dreamer and I should get used to it, or should I check something?
Regards,
Marian
A couple of weeks ago I finished this kit. I enjoyed a lot building it, no problem at all.
As this is my first biplane I hesitated a little bit before the first fly but than I flipped the propeller and "Let´s go ..."
I am experienced pilot (3D , pattern), but I was really busy to fly this one:
During the take off it moves on runway as on rails. Airborne: it gains altitude smoothly. When I try to make the first turn, at the beginning everything goes well, but suddenly it falls on wing. I was able to gain speed and level it, but from that moment I was much more tense. I tryed to land it at relatively high speed (just estimation, but it seems no coreect) but about 20 m before the runway the plane did not react to elevator and landed softly by itself.
The second fly was a little bit better: I added exponential to ailerons and throw to elevator. The take off was again very easy. I made all turns extremelly carefully to not repeat the same error.
I went for landing at much higher speed that with my pattern plane. The result was that I needed a lot of runway, but once it touched land it was again "as on rails".
CG is accoding to plans.
Is this behaviour normal for biplanes / Dreamer and I should get used to it, or should I check something?
Regards,
Marian
07-21-2008, 10:58 AM
#2
RE: Dreamer
The relationship between the top and bottom wing is very critical on a bipe.
If you have an incidence meter, check both wings. Usually, the bottom wing is Zero with the stab and the top wing is MINUS 1 to 1 and 1/2 degrees NEGATIVE to the stab.
If you have an incidence meter, check both wings. Usually, the bottom wing is Zero with the stab and the top wing is MINUS 1 to 1 and 1/2 degrees NEGATIVE to the stab.
07-21-2008, 01:13 PM
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RE: Dreamer
I have checked it again. The top wing´s angle of attack is 1/2 degree less that of the bottom´s wing. Although with this kind of cabane it depend a lot how do you positione the top wind. It can change +/- 0,5 degree.
I will try to positione it in the exactly same way as I had it during the measurement.
Any other idea?
I will try to positione it in the exactly same way as I had it during the measurement.
Any other idea?
07-21-2008, 09:10 PM
#8
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RE: Dreamer
My Dreamer flies an lands very fast but you will soon become acquainted with the landing speed. Biplanes don't glide as well as pattern airplanes and like to be flown to the ground with no flare allowing the speed to bleed off on the ground. However an engine that likes to idle at high rpm can make landing difficult. Looks like you have a lot of prop.
The control surfaces need very little throw and the airplane is very neutral.
Have fun it is a great airplane.
Bill
The control surfaces need very little throw and the airplane is very neutral.
Have fun it is a great airplane.
Bill
07-21-2008, 10:16 PM
#9
Senior Member
RE: Dreamer
My Dreamer was set up with everything 0/0. It flew well under power (OS AX .46) but was a challenge to land. I always commented that the Dreamer looks much better than it flys
-Johnny-
-Johnny-
07-23-2008, 05:43 PM
#10
Senior Member
RE: Dreamer
Flew my Dreamer again today to check comments about landing speed.
Like most Biplanes a slow idle rpm produces a very steep glide slope, which is expected and it lands easily. A high idle rpm creates a bear to land and it simply wants to continue flying. If the prop is turning a little fast at idle it is easy to understand difficulty landing.
Bill
Like most Biplanes a slow idle rpm produces a very steep glide slope, which is expected and it lands easily. A high idle rpm creates a bear to land and it simply wants to continue flying. If the prop is turning a little fast at idle it is easy to understand difficulty landing.
Bill
07-24-2008, 05:37 PM
#11
RE: Dreamer
ORIGINAL: Marian
During the take off it moves on runway as on rails. Airborne: it gains altitude smoothly. When I try to make the first turn, at the beginning everything goes well, but suddenly it falls on wing. I was able to gain speed and level it,.......
Marian
During the take off it moves on runway as on rails. Airborne: it gains altitude smoothly. When I try to make the first turn, at the beginning everything goes well, but suddenly it falls on wing. I was able to gain speed and level it,.......
Marian
In addition to previously mentioned ideas... I am wondering if you are using any differential in your ailerons? This may help. Sounds to me as you might be stalling out a wing with the ailerons.
A way to confirm this would be to try a rudder turn leaving the ailerons alone. Just something to try. Good luck.
07-25-2008, 12:25 AM
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RE: Dreamer
Marian....I have one of these and it is really a fine aircraft.Mine has now done over 60 flights and 12hrs flying. In the build I did change a few things..I put two small servos in the ailerons ,one each and a very small amount of differentail..Power is a OS40LA swinging a 10x6 prop...when hot a good low idle.also you might want to seriously look at your wing mounting. First off I dont use rubber bands ,it means that the wing can still move a very small bit,and each time you put the wings on you dont always get them it the exact spot each time.Secondly the cabane struts are very loss and the top wing can move around.I have made up fiberglass clamps and bolted the top wing on.Thirdly,USE the interplane struts they are there for a reason. I have made mine to bolt on ,after flying it with them only slotted as per plan.and it made heaps of difference the whole wing area is so muuh more solid.and the plane flew much better. Any time I go flying this is the first plane I take and often the only one I fly.It will land quite slow and fully in control right to the ground.When I decided to built this plane I had a look at this Rc site and there was so much negative about this plane I was a bit affraid to test fly it In the end just got on with the job and I really dont know what some of the guys did but it was really an anticlimax for the test flight. DONT change the rigging from the plan,as it is correct,just make sure you have it right. cheers Mintie
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