Introduction

It does not take long for an intermediate pilot to realize the need to convert his brushed micro heli to brushless. That said, the process may not plug-and-play. I am one of those who want consistent power and avoid regular replacement of worn out brushed motors, but on the other hand, I do not have time to learn about brushless mods well as getting my hands dirty to convert my V922 to a brushless setup. Some time back, I reviewed the Skyartec Wasp Nano CPX, and I thought that was the answer. But it was plagued with a problematic tail that made me quit flying it after some time. I had been waiting patiently for my next brushless micro heli since then...

On Jan 3, 2014, my friends at BG sent me a Chinese spreadsheet of four new “6G” heli; one of them was a 6CH brushless heli. What a great way to start 2014! Fast forward till Feb 17, the heli arrived. It could have gotten here a week earlier if not for the logistical screw up at BG.

I am thankful to Banggood for sending me a WLtoys V977 Power Star X1 for review. I hope my review can answer the following questions:

1. What are the key differences between V977 and V922?

2. Is V977 a significant step up from V922?




The Package

The unit that I received was the only sample that BG had received from WLtoys. It was before WLtoys renamed V977 from WL925. Strangely, the box shows “WL926” while the manual shows “V926”. But BG told me that WLtoys confirmed the heli as V977.

Check out the unboxing video for the package contents.




Battery

The package came with only one 450mAh 1S 3.7V battery. It is long and flat, which reminds me of Wrigley's chewing gum. I was able to fly V977 with my Solo Pro 100 batteries (Nine Eagles, need to swap polarity!) which I bought for my quads.

The SP100 battery fits “ok” but may come loose during tick-tocks. It was a disaster. As its capacity is only 300mAh, its flight time is about half of the original battery.

I found that inserting the original battery fully will shift the center of gravity forward. Apparently, the battery was too heavy to be fully inserted for the longer tail boom (as compared to the brushed V966). Maybe the front was too heavy due to the ESC?






The Helicopter



The tail boom looks a little too long for my liking. The vertical tail fin feels soft and may be able to withstand crashes better than V922. The tail rotor blades is similar to that of the V911.



I can’t tell if the 2mm square tail boom is glued to the frame. There are no screws locking the tail boom in place. The boom feels sturdy.

Instead of three linear servos, there are three rotary servos. I don’t think the helicopter performance was ever hindered by linear servos, so I’d say the use of rotary servos may not be a performance upgrade. On the plus side, rotary servos do not require cleaning. But the problem is they are prone to striping. Thankfully, there are ways to prevent striping the servos in a crash (see what folks do to their Walker Super CP).



At Idle-Up, 50% collective, the swashplate appears to be level. However, the servo arms are not. I would love to rectify that by the transmitter does not allow channel subtrims. The front servo is out of position (seated a little forward) as you can see that the linkage rod leans backwards.



The helicopter comes with a 120-degree swashplate, unlike V922. But I do not know if CCPM is performed onboard or on the transmitter. The anti-rotation pin sits right between the two rear swashplate balls, i.e. at 180 degrees. This may be good to reduce unwanted swashplate interactions.



The main rotor blades dimensions are exactly the same as those for V922 but without bullets. The blades feel more rigid and give me the impression that they are more durable.

I like the shiny brushless motor which has “WL-001” engraved on it. The motor is secured to the frame via two screws, which do not allow the position of the motor to be adjusted, for adjusting the meshing of the pinion to the main gear. That said, the meshing looks perfect to me so no adjustments are necessary.



The receiver board is horizontally mounted on a thick gyro mounting foam tape (approx. 2.5 mm). Below the tape there is a tiny tray that holds the tiny ESC in place. The ESC is fastened by a piece of white double-side foam tape. Below the ESC tray is the battery tray. The battery is secured in place by friction; no clips or grooves to lock it in place. It may shift position during fast maneuvers.



Before you spool up for the first time, make sure you examine the power cable extending from the ESC. Mine was in the way of the main gear. Ensure that you route the power cable away from the main gear.



The main gear, like V922, is friction fit to the main shaft. So check that there is no play at the main shaft after a crash.

The black foam “bumper” at the nose was cute. I’m not sure if it was to absorb impact (protect the electronics) or to hold the canopy in place.

The canopy is secured to the frame via two rubber grommets, unlike V922 which has four. I found that fitting the canopy to the frame was very tight. To relieve the tension, I could move the two holes on the canopy backwards, or trim away part of the bottom of the canopy as it was blocked by the front landing skid struts.

The two pins that secure the canopy look more fragile than the that of the V922. It seems highly likely to break on side impact. I probably should strengthen it with CA+baking soda. Unlike V922, the canopy pins are not part of the frame, but a “top part” plastic piece (also holds three servo and anti-rotation pin) so replacing them is easier and cheaper.

Landing skids are not as flexible as the first-generation V922 skids. They may not be durable so might be a good idea to stock up a couple of them.






Transmitter



It is gold in color. It’s a weird color choice for transmitter but I don’t really care how my TX look like. I don’t look at it while the heli is in the air. Nobody looks at my TX while the heli is in the air. More importantly, I kinda like a gold TX! It’s special!

Since we’re at the topic of “special”, I shall introduce the ability to toggle between 3D vs 6G modes. 3D mode = 3-axis flybarless stabilization; 6G mode = ??? (I’m not sure and I shall not comment or risk being FLAMED by some “happy” guy).

3D mode is exactly like flying a V922. Apply forward elevator the heli pitches forward and it flies forward. Release elevator to stick center does not stop the heli - it continues forward flight. At 6G mode, the heli levels itself once the elevator is returned to center. More flight characteristics in the next section.

At normal mode (toggle via the switch at the top-left corner), pressing the 3D/6G button switches between the two modes. Blinking red light (alert!) on the TX means you’re at 3D mode; solid red light means 6G mode.

At idle-up mode, activating 6G mode overrides idle-up mode sending it back to normal mode. So if the heli is inverted, do not activate 6G.

The “bind” button has nothing to do with binding the RX to the TX. Instead, pressing it three times goes into 6G gyro calibration mode (only works in 6G mode). Go into calibration mode, hover the heli, and apply the cyclic trims to eliminate drifting. Once you’re done, press the bind button once. While you’re trimming away, remember the number of trims required because the trim configuration goes away when you power off the TX.

The dual rate button toggles between L/H rates. Unlike V922, cyclic sensitivity differs significantly for L and H modes. Also, cyclic sensitivity differs between 3D and 6G modes. At 6G mode, cyclic is generally less sensitive than 3D mode. I found L mode at 6G to be too low, and H mode at 3D to be too high. Be extra careful when flying at L-6G mode as well as H-3D mode.

I have no idea what the “Mode transition button” is about. I don’t think I’ll need it anyway.

When powering up with throttle hold enabled, the TX does not complain. I’m glad they discovered throttle hold on power up is encouraged. Also, they implemented “sticky throttle hold”. As long as throttle hold is activated while the rotors are turning, you cannot deactivate throttle hold until you completely lower the throttle stick then disable throttle hold. For example: hovering at midstick, activate throttle hold, heli drops to ground, deactivate throttle hold, heli does not respond (applies to both normal and idle-up); so you have to activate throttle hold, lower throttle to 0%, then deactivate throttle hold. *catches my breath*



I believe that the stock transmitter, while still non-programmable, is a huge improvement over its predecessor.

Currently, I do not know ways to bind the heli to other transmitters or RF module. It is unlikely to work with WL-T6 / HT-8 or FlySky RF modules.

As the heli spools up, there is a sudden drop in head speed. I don’t know if it was part of the throttle curve, or part of the spool up sequence programed on the ESC (soft start?).



Pitch Ranges

I didn’t have time to measure the actual pitch readings. I don’t think it matters so here are some photos of them for you to have a rough idea.

Normal
0%


100%


Idle-Up
0%


100%



L Rate

Full elevator forward.



H Rate

Full elevator forward.






Flight Characteristics



Having brushless motor, longer tail boom, rotary servos, true 120-deg swashplate, middle anti-rotation pin, I expect it to fly differently than V922.

At 6G mode, the heli tries to level itself and eliminate drifting. A properly calibrated heli is able to hover handsfree in a small room for at least 5 seconds. Full rudder piros are surprisingly stable. The heli does not drift all over the place like V922. I call this piro compensation but if you don’t agree with this term, please do not clog this thread with your rants.

Flying about in 6G mode is a completely experience than on the V922. Cyclic controls has to be applied continuously and that is really awkward for me. I could pull off figure-8s but completely messed up my reverse figure-8s. My muscle memory is not used this mode.

At 6G mode, the heli is unable to as fast as in 3D mode. I believe the maximum angle to pitch and roll are limited at the FBL system. This means that you could apply full elevator at H rate and the heli does not flip over. The heli is unable to fly properly at L rate 6G mode. It’s seems to be for indoor hover practice.



The heli is able to glide across the windy sky with ease at 6G mode. The loss/gain in altitude is very minimal, maybe even non-existent. This is certainly not the case for V922. You can’t really mess up flying in 6G mode. You can’t go too fast, pitch / roll too much; when you are about to “lose it”, let go of the cyclic and let it help itself. Usually, I’d hit the throttle hold at that moment but that is not necessary for the 6G mode.

6G mode sounds like a really good feature until you decide to do some 3D flying. Switching to 3D transforms V977 to a radically different beast. If you have trained your muscle memory to apply constant pressure to the cyclic stick while flying, you’re in for a hard time. Within milliseconds of applying full cyclic, the heli would have flipped or rolled over. I crashed immediate at 3D mode after flying for a complete battery at 6G mode. I would avoid the 6G mode from now on.

Let’s switch to Idle-Up and deactivate 6G. Also switch to L rate as H rate is too much for me to handle. The head speed feels consistent but not as high as I hoped for. It does not allow the heli to do high-speed pitch pumps.

There are hardly any tail blow out. I could not trigger TBO during pitch pumps. Full positive and negative collective do not trigger TBO too. There seem to be very slight TBO during full collective and some cyclic, i.e. when I execute stall turns and loops.

With V922, stall turns and loops are hard to pull off. Not only I have to be wary about TBO, the inconsistent head speed makes the heli more likely to smash into the ground as it exits the loop. With V977, stall turns and loops are a joy to do. I could almost feel complete control of my helicopter as it transits from stall turn to stall turn, loops to loops. Due to my limited skill level, I could only do flips, rolls, reverse and inverted flight with my V922; now with V977, I am able to do more!



Like tick-tocks. Good idea if you have the skills; bad idea if you suck. Tick… tock… tick… crash! It’s impossible to even do a tock on my V922, but I did a little better with my V977. I probably should stop trying tick-tocks on micro helis.




Key Questions

1. What are the key differences between V977 and V922?

Brushless motor allows V977 to have a more consistent headspeed, enabling a more predictable flight. 6G mode may be useful for beginners who have difficulties hovering V922.


2. Is V977 a significant step up from V922?

Yes! The brushless motor gives you more confidence in flying basic figure-8s or fancy 3D moves, as the head speed is more predictable and hardly ever triggering TBO. And not forgetting the brushless motor does not lose power gradually like the brushed one.




Conclusion

WLtoys V977 is a capable brushless CP helicopter that is suitable for beginners as well as advanced 3D pilots. It offers significant improvements over its brother, V922. At a pretty decent price, you get a brushless CP heli with a decent transmitter that works. As I am not a Banggood rep, and Banggood is not the sole distributor of the product, please feel free to look around for best deals.



Mods

I might change the V911-style tail rotor to the Walkera Super CP style tail rotors, which was said to produce more thrust.

The red canopy and blades for V966 would look great on my V977! Looks like a micro Gaui.

Strengthen canopy pins with CA+baking soda.

Find other compatible batteries; has to be slim.



Pros

+ Consistent head speed
+ No need replace main motor regularly (does not wear out)
+ No need to clean servos or replace its carbon strips
+ Flies perfectly out of the box
+ Highly stable flight (at 6G mode)
+ Great 3D performance
+ Should be decently price


Cons

- No expo on the TX
- 3D mode H rate is too much for me to handle
- Servos may strip in a bad crash




Links

- Photo Gallery: http://www.flickr.com/photos/fyresg/...7641384551994/
- WLtoys V977 Power Star X1 RTF: http://www.banggood.com/WLtoys-V977-...-p-914247.html

Videos

WLtoys V977 Power Star X1 RTF Helicopter - Lots of piros! (4 min 50 sec)

WLtoys V977 Power Star X1 RTF Helicopter - Showcasing Paper Canopy (2 min 31 sec)

WLtoys V977 Power Star X1 RTF Helicopter - 6G Mode slow circuits & 3D Mode Flips (5 min 37 sec)

WLtoys V977 Power Star X1 Brushless RTF Helicopter - Loops! (4 min 39 sec)

Flying my V977 around (2 min 5 sec)

Official Product Video from WLtoys:

WLtoys V977 Power Star X1 Brushless Helicopter Official Video (2 min 51 sec)

Executing hardcore 3D moves indoor:

WLtoys V977 Power Star X1 Brushless Helicopter Hardcore 3D Indoors (3 min 14 sec)

Parts Compatibility

Legend:

• * : Reported to be compatible
• ? : Seems compatible (my guess)

1. Main Gear: FBL80 / HCP80 / V933; SH6050? Heli-Max AXE 100 SS?
2. Tail rotor: V911; FBL80 / HCP80 / V933; V922 / HCP100; MiniCP / SuperCP; SH6050; Heli-Max AXE 100SS; NE Solo Pro 125/126
3. Tail motor: V922 / HCP100, MiniCP / SuperCP, microquad 7mm CCW motors*
4. Servos: SH6050? Heli-Max AXE 100SS? NE Solo Pro 125/126?
5. Swashplate: SH6050? Heli-Max AXE 100SS? NE Solo Pro 125/126?
6. Battery: Heli-Max AXE 100SS? NE Solo Pro 125/126?
7. Rotor blades: non-bulleted blades such as V944 blades?, HK 107mm Carbon Fiber or Glass Fiber blades?, Bolt MCPX blades?, Tarot MCPX blades?.
8. Canopy: SH6050? Heli-Max AXE 100 SS? NE Solo Pro 125/126?
9. Landing Gear: SH6050? Heli-Max AXE 100SS? NE Solo Pro 125/126?

Useful Information

1. Recommended replacement parts
2. Transmitter calibration (video)
3. Paper Canopy (video)
4. Compatible rotor blades and my comments
5. CNC Metal Rotor Head Upgrade

Great review bud, cheers for the great read

Looks interesting! Do you know what protocol it's on?

great review, I have been watching this heli. If deviation hacks the protocol I will probably take the plunge. ps don't feed the trolls, if we didn't get reviews like yours how would we know which helis to salivate over and buy

Originally Posted by jameschen072

Great review bud, cheers for the great read

Glad that you enjoyed it! I'm keen to read about your thoughts on the new brushed variants.

Originally Posted by SLMcc

Looks interesting! Do you know what protocol it's on?

Sorry but I have no idea. But I noticed the TX LCD on power up, shows all possible options:



I see V922, V933, V944, and V955 in there! Hmm...

Originally Posted by Greg Head

great review, I have been watching this heli. If deviation hacks the protocol I will probably take the plunge. ps don't feed the trolls, if we didn't get reviews like yours how would we know which helis to salivate over and buy

In the past, I would expect a CP heli to be controlled by a programmable TX. After flying V922 with stock TX and then this one, to be honest, I don't think switching over to a programmable TX would be a huge improvement. Maybe the greatest advantage is one less TX to carry around, but feature wise, I'm pretty happy with it.

A brushless micro heli is so much more fun to fly. If you give this one a miss due to its TX, then you probably should get a BNF Walkera Super CP and convert it to brushless. I guess I'm a brushless fanboi now!

And thanks for your kind words.

Originally Posted by FyreSG

Glad that you enjoyed it! I'm keen to read about your thoughts on the new brushed variants.

Sorry but I have no idea. But I noticed the TX LCD on power up, shows all possible options:



I see V922, V933, V944, and V955 in there! Hmm...

In the past, I would expect a CP heli to be controlled by a programmable TX. After flying V922 with stock TX and then this one, to be honest, I don't think switching over to a programmable TX would be a huge improvement. Maybe the greatest advantage is one less TX to carry around, but feature wise, I'm pretty happy with it.
)

Thanks for the review. I did find the stock V922 transmitter too mild for 3D. Looking at the videos, it seems that the new crop of micros have much more aggressive settings. Perhaps the ideal would be to have two idle up settings: moderate and aggressive.

I would not be surprised if you seeing the V922,V933,V944 and V955 in the display ONLY means that they use one single display for all of their transmitters.
It would be nice if they all were controllable from one TX, but the mere presence of these models to me does NOT imply "availability" ...

(my bet would be it is simply a measure to keep cost down by using ONE standard part in ALL "new" transmitters)

Originally Posted by zadaw

Thanks for the review. I did find the stock V922 transmitter too mild for 3D. Looking at the videos, it seems that the new crop of micros have much more aggressive settings. Perhaps the ideal would be to have two idle up settings: moderate and aggressive.

I remember that you like to fly your micros aggressively. You should try the V977, 3D mode, H rate. It may be just nice for you!

At low rate, I did not have to apply full cyclic to flip or roll the heli. H rate was so sensitive that I was actually worried the cyclic travel would be too much that bogs the motor; glad that it didn't.

Originally Posted by erdnuckel2

I would not be surprised if you seeing the V922,V933,V944 and V955 in the display ONLY means that they use one single display for all of their transmitters.
It would be nice if they all were controllable from one TX, but the mere presence of these models to me does NOT imply "availability" ...

(my bet would be it is simply a measure to keep cost down by using ONE standard part in ALL "new" transmitters)

I think you're right! James confirmed recently that V977 does not use the HiSky protocol that V922 / V933 are using. Your reason also explains the light bulb icon (trigger search light on/off ), as well as the camera and video camera icons, are actually for the other helis like V912.

How does the CA and baking soda work for strengthening the pins? Even with the BL, gonna be a hard sell the heli is not deviationizable....

CA mixed with baking soda transforms it into a thick crust. I can't explain it any better. You might want to try some CA + baking soda on used paper to see it in action.

Maybe the V977 will not be as popular if it does not support DeviationTX. However, I don't think it will be "hard to sell" this helicopter. There are people who do not mind using the stock TX, as well as some who does not have a Devo (like me ).

For you guys already with a Devo, SCP + brushless mod seems to be the better option. For the rest of us, this could be it.

Great review

i) Did you tried to bind it with a [V922-V955] TX ?.

ii) Can you take some close up photos on FC board, RX part as well as for the ESC board ?
(wondering if it can reprogrammed with an USBAVR)

iii) What is the weight w and w/o battery ?

iv) Are blades compatible with V922 ?

v) If you have a salaeae logic analyser and not afraid to make some soldering to sniff TX packet, you can deviatiotx communauty

Yet again, very informative with fantastic write up and pictures.
Your reviews will be the decider on what I opt for after my fbl 100.

I do like the look of this, hope it's not mega expensive and available to the UK soon.

Ooohhh, nicely priced on banggood

Great review as always FyreSG :-) thanks for your time and effort in putting this together.

Looks like I've found my next micro :-)

@FyreSG， thanks for your great review.