PART 1 : Unboxing and preliminary issues


I was looking at the various 100 size CP helicopters, specifically to use as a trainer and for indoor flight. I wanted a helicopter that was well-made, inexpensive, and had a programmable transmitter.

I finally narrowed it down to the v922 (from WL Toys), the Mini CP (from Walkera), and finally the Wasp Nano CP from Skyartec.

Since this was going to be a trainer for my 250 class FBL, which was from Skyartec (Wasp X3V), so I decided to get the Wasp Nano CP.

I already had a NASA-701 transmitter, but I could not find any bind and fly version, so I just got the complete package in aluminium case.




The package arrived covered in a layer of bubble wrap and plastic, and within was another cardboard cover:



Inside this cardboard cover was another layer of bubble wrap, and finally the aluminium box:



If you take a look at the top right edge, you will note that the edge is mildy dented, so all that protection may still not prevent your shiny aluminium case from getting a few dents during shipping!

Included
1. Helicopter body
2. NASA-701 receiver
3. 1 piece 240 mAH LiPo battery
4. Spare main and tail rotors
5. Skyartec CD
6. Charger and USB type cable
7. Screwdriver and spare screws
8. Keys for aluminium case
9. Aluminium case



Helicopter

The helicopter is well made. The landing gear and skids appear solid, and it is detachable. I believe the Mini CP landing gear is supposed to fit.

After a few crashes, the ends of the skids broke off, but the gear can still be used. Here is a simple training gear I've made to reduce tip overs:







Here are the main and tail rotor dimensions:



The tail rotor is identical to the one on my WL Toys v911.



The tail boom is nicely secured and 2.5 mm x 2.5 mm in dimension. The tail rotor:



The tail motor is protected by a plastic encasing that also covers the motor wires:





The three servos are 2g 5 wire type, meaning they do not have internal electronics and will be controlled from the PCB:




Canopy issues

The canopy I got came with a break at the bottom:

As you can see, the canopy has cut slots at the bottom, which go through the landing gear when the canopy is attached.



I did not think this was going to last very long, so I used transparent Scotch tape to reinforce the slotted parts, the broken area, and also applied strips to the inside of the canopy.



All this changed the weight of the canopy from 2.4 g to 2.8 g.

After some crashes, the canopy only developed breaks where there was no Scotch tape, so this mod works. It seems that the tape should be applied all over inside.

Two thin carbon graphite rods are included, and these need to be pushed into slots at the side. You will need to be careful doing this, otherwise you run the risk of breaking them.



The grommets at the back of the canopy go into these. I have to admit I have a bad feeling about what will happen to these flimsy rods after a crash!

Another more serious issue was that the elevator servo rod was impinging on the canopy. Here is a picture of the canopy:



I cut a small area and then filed it, and now the servo rod can move freely:





Battery

Some sellers are including 3 batteries and charging more for the package, mine only came with one. Update: a BNF package has now become available, and that comes with 3 batteries. The battery dimensions are 32.2 x 20.4 x 7.6 mm. Weight is 7.9 g. The battery capacity is 240 mAH, and it is rated at 25C.




Battery life is quite impressive! Flying in beginner mode at a cold temperature (5 C), the battery lasted just over 5 1/2 minutes of flight.
See the flight video in my post "Flight Characteristics".

With training gear attached, and mostly hovering, I was able to get at least 5 1/2 minutes as well.

Inserting the battery was not easy. It would just not go in. After squeezing the plastic at the side of the battery, I finally managed to push it in. If someone is going to use multiple batteries, they are going to have a hard time inserting and removing them, at least initially. This is the type of plug used:



The charger is a simple one, rated at 5 V and 500 mA.



A fully charged single cell Li Po should be at 4.2 V, my particular charger charges to 4.24 V. A LED on the USB charging cable (circled yellow in the picture) turns red to indicate charging is complete.





Flight modes

The Nano CP has two flight modes, the ‘beginner mode’ and ‘aerobatic mode’. These modes are apparently programmed into the receiver. There is a small button at the top of the receiver, by pressing it for 3s, you can toggle between the two modes.



If you are in the beginner mode, a green LED will light up, and a red signifies the aerobatic mode. The last mode is remembered when you power up each time. The manual does not explain what exactly the beginner mode does.

NASA-701 transmitter

The NASA-701 is a relatively new product from Skyartec. It is designed for use with planes, gliders and helicopters, both flybarless and flybarred. It is fully programmable, and gives 5 point throttle and pitch curves.

The LCD display does not have a backlight and does not display graphical representations of curves.

It comes with a battery holder, which needs to be plugged into the transmitter. I am using it with 8 AA size alkaline batteries, but a rechargeable battery pack can also be used.

There are two toggle type switches. The one on the left is for throttle hold, while the right one is for idle up. If you have them in the wrong position when you power up the transmitter, it will beep and flash to warn you.

If you have two NASA 701s, you can use them wirelessly in an instructor and student setup. By moving the left 'ear' on the instructor transmitter, the instructor can switch control between the student and himself.

For details about how to do this, please see this post by Skyartec:

http://www.rcgroups.com/forums/showp...1&postcount=52

Mechanical problems

I discovered that one of my blades would not move freely, and the servos seemed to be struggling and ‘catching’. Had I stripped one of the servos? Was the pitch axis damaged? It eventually turned out that the ball-link at the blade-holder was so tight that it was even difficult to move by hand.



I cannot understand how this could have been test-flown at the factory.

Using a simulator with the NASA-701

The NASA-701 transmitter has a 5 pin DIN type of plug at the back, which can be used to connect to simulation software. Unfortunately this type of plug does not seem to be very common. This is the type of plug used:




Also many Wasp Nano CP sellers do not seem to be carrying the Skyartec HS-041-1 USB dongle type of adapter (cost $ 10-12). Personally I would have rather got this with my package than an aluminium case. The adapter:



It includes a cable, USB dongle and a CD. The CD contains Clearview SE. I was not able to get HeliSim RC to work on it.





Flight characteristics

After correcting the mechanical problems I encountered, I have found the Wasp Nano CP pleasant to fly. Please see the next post Part 2: Flight characteristics for details which I will keep on updating.


Review version history:

1.1 Added more pictures and dimensions of the battery, blades
1.2 Added information about battery time, using the transmitter for training, canopy strengthening, training gear and finally a flight video.
1.3 Added more pictures and information about the battery and simulator. Moved the flight characteristics section.

Part 2: Flight characteristics

Update 1 (30 Dec 2012)

Well I have to say that "Beginner mode" does work! With zero simulator practice, and only 4 channel FP flying (v911 and F-45), I was able to take it off and actually fly it, for my first proper controlled 6 channel CP flight. It flew beautifully, though flew backwards quite fast about 10-15 feet before I managed to control it. I did not seem to be having much, if any, aileron response, though.

I had modified the pitch curve, to give less negative pitch at points 1 and 2, otherwise all settings as per the factory.

I flew it in an open area, with grass, and no spectators around in zero wind. Flying over short grass has been reported as decreasing the risk of damage following a crash. I have also found out that to land the heli over grass, the best way for someone with my limited CP skills seems to be to bring it to a low altitude (a few feet above ground) and then hit the throttle hold, rather than landing under power.

I have to say that I'm very pleased with it, and it seems to bear out Skyartec claims of it being 'beginner friendly'. My previous problems were due to mechanical reasons, and it would be a good idea to buy from a seller who actually does a flight test before shipping it, if you are a beginner.

I'll see if I can find someone more experienced to try it in aerobatic mode and try some 3D on it.

Update 2 (9 Jan 2013)

Here is a flight video. The heli was flying in the green 'beginner mode'. The pitch curve was using less negative pitch at the first two points (40, 45, 45, 55, 60) Pilot: Burhan I. The 'sticks' on the landing gear are training gear I made for myself

RC-Fever x Skyartec Wasp Nano CP outdoor flight (5 min 24 sec)

Update 3 (27 Jan 2013)

I got this heli as a trainer, and I must say it has worked! I am now using the pitch settings recommended by the manufacturer. The trickiest part (for me at least) was learning to take-off without tipovers and flips.After some practice on it, I am now able to hover and slowly fly my 250 class CP (Skyartec Wasp X3V). The Wasp Nano CP is quite agile, even in the green mode. The tail is very stable, though there is some tail wag (as expected) during pitch pumping. The gyro works well to stabilize the helicopter. The gyro does not require re-initialization after landing. Response is fast but controllable. Its actually easier to hover this compared to the V911 (4ch. FP). Battery time is in excess of 5 minutes, even with my training gear attached and near continuous hovering. After 5 minutes, the motor is hot to the touch.

Reserved for a supplementary review of the brushless version.

Nice review. I have some questions hope you can answer.

Can you measure the dimensions of the tail boom? Is it 2.5mm x 2.5mm x ??? What is the length of the main rotor blade? Can you also post a close up picture of the tail rotor blade and its length? The battery looks like one of my micro quad batteries. Can you measure its dimensions as well?

Can you elaborate on the difference in "feel" between the beginner's and aerobatic modes?

I noticed it doesn't come with the bulleted rotor blades. I wonder if you have them to try. Perhaps it may improve the stability.

Originally Posted by FyreSG

Nice review. I have some questions hope you can answer.

Can you measure the dimensions of the tail boom? Is it 2.5mm x 2.5mm x ??? What is the length of the main rotor blade? Can you also post a close up picture of the tail rotor blade and its length? The battery looks like one of my micro quad batteries. Can you measure its dimensions as well?

Can you elaborate on the difference in "feel" between the beginner's and aerobatic modes?

I noticed it doesn't come with the bulleted rotor blades. I wonder if you have them to try. Perhaps it may improve the stability.

Thank you!

I appreciate your feedback, it will allow me to update the review.

The basic purpose of this review was to provide some information from the perspective of a beginner who had purchased the helicopter as available in the open market rather than a 'cherry picked' test specimen.

I've added pictures with dimensions and a close-up of the tail rotor. The boom is indeed 2.5mm square. I've also given the battery dimensions.

I don't have the bulleted blades to try.

Also I'm too inexperienced to try the aerobatic mode as yet. I'll try and get someone else to do this.

thank you for your feedback.

Habby new year!

Thanks for the review. I've also been looking at this as a potential first CP. If I have to buy a TX I would at least like to be able to tune down the rates. It would be nice if this had dual rates on the TX for in flight but it still appears to be a improvement over the V922 TX. I watched a video on YT showing how flexable the plastic is which seems to be a common Walkera complaint. Banggood is selling a nice assortment of fairly affordable parts for this bird which is also a big plus.

Originally Posted by Stevez1kart

Thanks for the review. I've also been looking at this as a potential first CP. If I have to buy a TX I would at least like to be able to tune down the rates. It would be nice if this had dual rates on the TX for in flight but it still appears to be a improvement over the V922 TX. I watched a video on YT showing how flexable the plastic is which seems to be a common Walkera complaint. Banggood is selling a nice assortment of fairly affordable parts for this bird which is also a big plus.

If you do get it, please let us know, we need more users!
What heli have you been flying?

Originally Posted by skyartec

thank you for your feedback.

Habby new year!

Happy New Year!

Please keep following this thread, which I hope will also be used by other owners. Right now I have to post my questions on the mini CP thread since no one else seems to have this heli as yet.

I have some questions for you:

1. What would you say about a pitch curve of -1, 0, 5, intermediate value, 10 degrees, in 'beginner mode' instead of zero pitch at mid-throttle?

Throttle curve will remain the same.

2. What is the function of the two 'rabbit ears' on each side of the transmitter?

tomorrow,I try to make a video to show it.

keep zero pitch at mid stick. Every cp heli you fly will be set up this way and you don't want to learn where zero pitch is wrong early on. You can have zero pitch on both the 2 and 3 points on your curve if you are afraid of negative pitch I guess.

I suppose if your aim is the fly 3D eventually, it is best the keep zero pitch at mid stick early on. Otherwise, most beginner settings I have seen aim to achieve take off at half throttle.

I wouldn't worry too much about this heli at the moment. It must have something going for it in order to do so well against the Mini CP in Taiwan. However, it is possible that if flies quite different to the Mini CP, as the V922 flies quite different to the mCPX.

Originally Posted by zadaw

I suppose if your aim is the fly 3D eventually, it is best the keep zero pitch at mid stick early on. Otherwise, most beginner settings I have seen aim to achieve take off at half throttle.

I wouldn't worry too much about this heli at the moment. It must have something going for it in order to do so well against the Mini CP in Taiwan. However, it is possible that if flies quite different to the Mini CP, as the V922 flies quite different to the mCPX.

I have a feeling that the higher headspeed associated with a liftoff at 70% throttle is giving me a tendency to a rightward tipover. If I can hover at 50% throttle, don't you think this tendency would be reduced?

I think that the most difficult part is taking off in a 'controlled' manner, at least for me....

Originally Posted by Lentar

I have a feeling that the higher headspeed associated with a liftoff at 70% throttle is giving me a tendency to a rightward tipover. If I can hover at 50% throttle, don't you think this tendency would be reduced?

I think that the most difficult part is taking off in a 'controlled' manner, at least for me....

Generally, the higher the head speed, the more stable the heli. However, the gyro could be affected by vibrations at a higher head speed. You can definitely try it out and see whether it makes any difference. I used something like -2 to 10 degrees range before.
'

Originally Posted by zadaw

Generally, the higher the head speed, the more stable the heli. However, the gyro could be affected by vibrations at a higher head speed. You can definitely try it out and see whether it makes any difference. I used something like -2 to 10 degrees range before.
'

If we compare the v922:

1. What kind of pitch does the v922 have at mid-throttle on the normal flying setting?

2. How 'easy' is it to get it into the air? Does it allow a slow lift-off?