Kamis, 29 Mei 2014

Details on creating "36s DJP"

As always, referring to built one and making improvement of it gradually...

It started with taking my Delta Jet Blue into my bedroom. Put it on 2x1 M depron sheet (6mm thickness)...

Learning from the mistake made and imagining what the jet plane would be look like, as you can see how it was started by looking at the pic below:


The spar (skeleton if i may say) comes from Shoe Rack bought from Giant Supermarket. I believe it was strong and it's been proven ...yes...it is so strong and could be considered light also (rather than putting fiber carbon spar which is more expensive).

The imagination is clearer when putting the  EDF on to the sheet:


Once, the look seems ok and as always, we can estimate how it will fly by using the following URL:

http://www.ef-uk.net/data/wcl.htm

I would consider creating an RC airplane as an art work since it depends on what kind of plane and characteristics would like to build.

Creating the can bee seen as the two pictures below:

1. Put the tape on the outer surface, the wing edge.


2. Cut excessive foam before folding it.



3. Now, it is ready to fold it.


As you can see form the latest picture above, i put coroplast in the fuselage to enforce it and it is good when attaching the battery onto it.

Now, we need to prepare the spar and engine mount.


Can you see that the wood comes from the shoe rack !

This is the look when the EDF was mounted into it:


Do not forget to put CA into the screw holes to make it stronger.

This is the look when putting them together:


Now, it is ready to glue them with "hot glue".


Up to this, you should get an idea already how the plane was made....

Minggu, 18 Mei 2014

BlueSky Coroplast transforms to Depron Jet Plane - 70mm EDF * name it 36s DJP (stands for Delta Jet Plane) *

The picture was taken during the clear sky morning.

Once upon a time/approximately one month back , I was thinking of making a new EDF jet plane inspired by the BlueSky. The Plane still uses the same EDF size 70mm with battery ranging from 3s to 6s. It means the power between 450 watts to more than 1000 watts. The construction, control surface and servos should strong enough to take 1000watts and 6s battery.

The picture below shows the draft during the planning step:

Got an idea, put on the paper and later ...execute it!


The first transformation step :)


To come with strong wings and fuselage, the wood spar and bamboo are used. The picture below shows what the plane is made of:


 The wing spar wood comes from the shoe rack and the fuselage spar comes from bamboo curtain all sold in Giant Supermarket.

Today, I was able to fly and also video it. You can see how this plane flies, please visit to the blow URL link:

http://www.youtube.com/watch?v=g1bB3-01IfE

Some pictures are also taken below showing the planes:





Sabtu, 22 Maret 2014

Coroplast Ver 4.0 in One Page

After completed the work:


The Fuselage:


The Engine Mounting:


Vertical Stabilizer:


The Rudder:




The Wing:


Tail Wheel:



Jumat, 27 Desember 2013

Coroplast Ver 4.0 - 150cm/43.5dm2 (called it ver 1.0 wing ) vs 170cm/51dm2 (called it ver 2.0 wing)

During the fly, it feels that the plane has less power than expected. The weight is about 3.7kg (not fill tank), the wing used is 150cm/43.dm2. If we calculate, the figure would be (see figures below). After changing the wing with wing ver 2.0, it changes the plane maneuverability/speed/etc. dramatically. It shows from the calculation below, lesson learned, it is not merely the power but it also depends on the wing load and watts per kg determining how your plane would fly ! ...


In summary:
- Calculate your WCL number and plane characteristics.
- Once you have the WCL, please take a loot at Watts/Kg your power RC plane installed.
Both will determine how your plane will fly beside other things such as control surface, length/width of your wing, location of your CG, and other things...

from http://www.ef-uk.net/data/wcl.htm
With ver 1.0 wing the calculation:

With ver 2.0 wing the calculation:

There are many excellent website to calculate Watts/Power requirements for your own design airplane, some examples:

http://www.motocalc.com/tutorial/
"
...

Determining Power Requirements

Regardless of the motor, battery, and propeller eventually chosen, any airplane needs a certain amount of power to achieve a desired level of performance. One simply cannot get around the laws of physics. Because of this basic fact, a number of "rules of thumb" have been proposed based on a plane's power to weight ratio. For example, it is suggested that a plane have about 40 to 60 Watts of power per pound (88 to 132 W/kg) of aircraft for typical "sport" type flying. More aggressive aerobatic flying requires about 70 to 100 Watts per pound (154 to 220 W/kg).
...
"
http://www.rcgroups.com/forums/showthread.php?t=29480
http://www.rcuniverse.com/magazine/reviews/976/ampd3.pdf

Coroplast Ver 4.0 - size 52 - 91 RC Plane




Coroplast ver 4.0 - size 52 - 91

After making 3 previous coroplast plane and learning from some mistakes, finally the ver.4.0 flies. It was not so powerful plane with 43.5dm2 (wing span 150cm) with ASP 52 2T since the wing load is considered more than scale aeroplane. After making the wing load with 51dm2 (wing span 170cm), it flies awesome and can do aerobatics move.

Another thought, i would like to upgrade the engine to 91 2T size. It seems that JBA 91AR is good for the plane. It will add the weight about 300-400 grams but the plane is still considered between aerobatics and scale plane. With this engine, I would expect having awesome speed and crazy maneuverability.

The specification can be seen below:

AUW : 3.6 – 3.8 Kg
Wing Span : a. 1.5 Meter and 43.5 dm2 for ver.1.0; weight approx 1.1kg.
            b. 1.7 Meter and 51.0 dm2 for ver.2.0; weight approx 1.1kg.
Engine : ASP 52 2T, plan to upgrade to JBA 91AR 2T.
Length: 130cm from the spinner to edge of elevator.
Propeller: see the engine specification below what it can accpet. For ASP 52T, my favorite propeller is 12x5
Servos: - 1 * 12g servo for throttle
            - 3 x 30g (2x mini servos for the wing and 1x for the rudder)
            - 1 x 50g (standard servo for elevator)

Engine specification can be seen below:

Type: ASP S52A II - now

Displacement: 8.477cc 
RPM range: 2,000-18,000(r.p.m)
Output: 1.47/17,500(kw/r.p.m) 
Weight: 475g 
Suitable Prop:11*7-12*6

Type: JBA 91AR - future

Displacement: 14.9cc
Bore (mm): 28.12
Stroke (mm): 24
Output (hp/r.p.m): 2.4/17000
Crankshaft: 5/16 x 24
Weight (oz) : 25.96
Recommended prop size: 13 x 8
Practical range: 2500/10500

I have not got a change to video it but soon I will make one...

Please see the picture below from some views :


Soon I will post the details...

Regards,
DS.

Rabu, 30 Oktober 2013

Billy and Me - Nitro Coroplast Planes from v1 to v3

It's always fun when I and Billy go for flying our RC planes.

The three planes in the pictures are all homemade planes. They are made from Coroplast and the engine is ASP 25 and ASP 32. The right one is my first homemade nitro engine and the left is the latest.

Hope you have happy flying also...


Selasa, 29 Oktober 2013

Before RedThlon, There was BlueSky EDF

My experience tells me that Coroplast is also good for EDF Jet type of plane. I started with around 500watts EDF, with static thrust ratio about 1:1. The battery is 3S 2200mah - 3000mah was able to build and fly the EDF plane named it BlueSky EDF Jet.

The advantage of using Coroplas is that it is resistance to soft to medium crash. It may be survive also for hard crash depending on the case.

Here is the picture of my BlueSky EDF:


The plane was inspired by this URL: http://www.mugi.co.uk/

Updated the figure with some measurements:



It is simple and so much fun to fly with. Have a change to upload the videos into youtube despite to shaky. Here are the URL for the videos:




Later I will post some screenshots during the making.