This is the 1st Jet plane i have ever had, very nice and lots of fun to fly. 1st flight was awesome, only needed a small amount of up trim to level it out at 3/4 throttle. I fly with a 3S 1300mah battery and get about 3 minutes with about 25% battery left. Landing are super easy on the grass without having to deal with wheels. Does have a pretty good approach speed when landing. Hand launching is easy once you get the hang of it. 1st time i had someone launch it for me because i wasn't sure what it was going to do. GPS speed of 86.4mph was verified with the use of a on board GPS. It is fast enough to start learning how the jets handle. Also it slows down pretty good for landings. Very happy i purchased it and Arrows Hobby did a great job of manufacturing it. You can't got wrong with this 50mm jet for your first jet experience.

This plane is so much fun that I just purchased another. We fly them in groups as much as 8 or 10 at a time racing. Has a decent glide. Inexpensive to operate.

This is a great trainer jet and it is a lot of fun to fly and is easy to keep it close to you and it will come alive on 4s 1300 lipo battery !!!!

Well let me tell you , this little guy packs a big punch in all category's , its quick, its agile, its VERY stable, it has a bold color scheme(great for orientation) and most of all it takes a beating!!! Here is a video where my dumb but did not check the center of gravity first and broke my nose on the plane. https://www.youtube.com/watch?v=Nx9VxxK698w FYI, a little glue and now you can not tell I broke it!!

Santa brought this airplane for my husband. He really wanted it. All the “cool” kids fly these at the flying field. He says it flies well and he was very excited to receive it. 

Super fun plane ! Flies on rails and handles like a dream!
Sharp looking value packed jet that will not disappoint !
This vale cannot be beat.
10+ stars !

Love this jet! The quality, detail, precision and advertised promises are real. I am truly impressed with the Viper and even more impressed with the brand. I do however think a 1300mah battery is not enough to power the jet well. A 2200mah battery is much more satisfying, and it will fit if you mount it as far back as it can go, behind the velcro strap. The hand launch was just as easy as a small battery.

Flying it is easy. My grandson is flying it bad he's 9 years old.

First, I am amazed at the quality in packaging, detail, fit and finish. Secondly, this jet flies so we'll mannered. I couldn't ask for more. I absolutely love this jet and even more impressed with the ArrowsRc brand. Great job! Looking forward to more releases!

One caviat, the 1300 3s sized battery recommendation I feel is not sufficient. A 2200 3s size is a better option. Doesn't change the flight or launch characteristics, but does supply the needed amperage and provides decent flight times

I’ve flown my Viper on 3S and 4S batteries and the 4S battery truly makes the plane live up to its Viper name. Really thought it was quite anemic on a 3S battery. Only put in two flights on a 3S and said enough of that! Had to really give it a good toss when hand launching on a 3S to get it going, while with a 4S it just pulls itself right out of my hand with a gentle under hand toss. On an amp meter the Viper showed it pulling a short peak of 35 amps using a fresh 1600 4S 70c battery. Since the Viper comes with only a 30amp esc, I put in a Mantis 35amp esc that allows for 45amp bursts. Also used the Mantis 35amp esc because it’s pretty small and with just a bit of shaving of foam of the inside the plane, I was able to put it in the same spot as the original 30amp esc. I push the Viper hard going full throttle with this setup and haven’t had any issues at all the esc shutting down. Also, I used some hemostats to separate the wire connections between the motor and the esc and use them again to hook up the bigger esc to the motor. That way you don’t have to do any cutting into the foam to get to the wires to disconnect and reconnect. The plane goes, as they say, like a bat out of you know what! Trust me, you’ll never want to fly the Viper again on a 3S. Downside is that my flight times using the previously mentioned battery while going full throttle are only 3-4 minutes at most. But totally worth it! Additionally, I set my Viper up with an Admiral gyro receiver and set up flaperons to slow it down and provide more lift for landings since it comes in a bit hot and drops pretty quick once you get off the throttle if you don’t have flaperons set up. Overall, a rock solid jet in build and flight that won’t disappoint you in its performance!

I’ve flown my Viper on 3S and 4S batteries and a 4S battery truly makes the plane live up to its Viper name. Really thought it was quite anemic on a 3S battery. Only put in two flights on a 3S battery and said enough of that! Had to really give it a good toss when hand launching on a 3S to get it going, while with a 4S it just pulls itself right out of my hand with a gentle under hand toss. On an amp meter the Viper showed it pulling a short peak of 35 amps using a fresh 1600 4S 70c battery. Since the Viper comes with only a 30amp esc, I put in a Mantis 35amp esc that allows for 45amp bursts. Also used the Mantis 35amp esc because it’s pretty small and with just a bit of shaving off of foam inside of the plane, I was able to put it in the same spot as the original 30amp esc. I push the Viper hard going full throttle with this setup and haven’t had any issues at all the esc or motor shutting down. Also, I used some hemostats to separate the wire connections between the motor and the esc and used them again to hook up the bigger esc to the motor. That way you don’t have to do any cutting into the foam to get to the wires to disconnect and reconnect. The plane goes, as they say, like a bat out of you know what! Trust me, you’ll never want to fly the Viper again on a 3S. Downside is that my flight times using the previously mentioned battery while blowing through the sky are only 3-4 minutes at most. But totally worth it! Additionally, I set my Viper up with an Admiral gyro receiver and set up flaperons to slow it down and provide more lift for landings since it comes in a bit hot and drops pretty quick once you get off the throttle if you don’t have flaperons set up. Overall, a rock solid jet in build and flight characteristics that won’t disappoint you in its performance!

This small RC model is so much fun to fly I can't tell you how much I enjoy it ,one of my all time favorites ! Just get one and you will love it.

Goes together easy and flies great! Plenty of speed on a 1300 3S. Fun jet for the price.

This jet is sick! It sounds cool, it's pretty fast and it's easy to fly.

Easy build and we'll manufactured

The Viper goes together quickly with only gluing on the tail and wing tips. Install your rx and you are ready to fly. Gives at least 5 minutes with a 1300 3S battery.

My first EDF jet and it was a BLAST to fly. I used a 6 channel Spektrum receiver mated to my de6 Spektrum radio. My hand lunch was a little shaky but the Viper is a forging plane. Vertical is unlimited as you can fly it straight up until it is so small you can barely see it. NO JOKE, oh and it gets up there in a hurry! The red and white trim is very easy to see and the gloss black hatch jumps out at you when you are flying nose in. In short, two thumbs up. Get one and reach for the sky.

Awesome ducted fan jet!...very easy to fly! highly recommended to anyone thinking of trying ducted fans. Quality is superb overall...fit and finish is almost flawless...!

I broke it the first time out. It broke at a factory joint that had almost no glue, that's why the 4 on quality and durability. After I glued it back together everything has been great.

I've been flying RC forever but this plane is my first EDF and I didn't know what to expect. I have been very pleasantly surprised! I've been flying it on a 20 acre sloping hayfield and it's perfect for that. Hand launches are simple and use the slope to give me a bit of time to get it under control. I fly with a gryo and a 3S 1300 all the way forward. It's stable as a rock but also very responsive. Even on mid-rates rolls are super fast, and vertical performance is impressive. It stays stable and controllable even at low speed. I've tried a 3S 2200 pack all the way back but don't like the drop in performance due to the extra weight. I think a 3S 1800 might be the best compromise between weight and flight time. I get about 3 minutes with the 1300. Overall this is a really fun plane to fly and not that difficult if you are used to planes that go where you aim them. Biggest challenge is keeping it close enough to see and slowing it down enough to land.

This plane is pretty cool for the price. It flies just like the Eflite viper. It’s just smaller and easier to transport. It’s so simple to cart and fly. Very reliable and I was also impressed because it wasn’t effected by the wind as much as I thought it would be due to its size, but it does quite well. Obviously it’s not as much fun as the 70mm viper but man it really shows up for its size which brings me to another impressive note. The fan actually sounds nice for a 50mm. Again I was very impressed. Nice job on this one. I’d sure like to see more reliable micros like this one. F16, F22, A4, maybe even a Mirage or SU-30, or MiG 29. Omg that would be an awesome 50mm lineup. 

This is the best flying, best sounding, best designed, and best materials on a small EDF I've ever seen! It's listed as a 50mm but it is the size of the 64mm jets that I have, like the Panther and the F-86. It's a definite "two thumbs up"! I can't say enough good things about it. The hand launches are super easy, way more power than my 64mm jets. Oh, and it gets a 5 minute flight on a 1300 mah battery. Incredible! I already recommended it to my friends. Keep up the good work Arrows!

This is a fantastic plane. It is simple as it is only 3 channels, but it is so much fun. It has a wide flight envelope, being able to fly slow or fast and still be stable. I fly mine on a 3s 2200mah 30C battery and easily get 5 minutes with mixed throttle. I spend most of the flight at full speed, so I am sure I could milk 6 minutes out of it if I slowed down for more of the flight. It is relatively quick and sounds great for a 50mm EDF. I kept balking at pushing the button, but I am glad that I finally did. I thoroughly enjoy this jet. The only reason I gave it a 4 on the value scale is that shipping to Canada adds a decent sum on the price (an extra 20-25%).
Keep up the excellent work, Hobby Zone. You guys are turning out some fantastic planes under the Arrows RC name!

The Viper is my 2nd EDF, the first being a "first generation" model that was difficult to launch and mediocre to fly. Not so with the Viper! With a bit of up elevator trim (programmed to a switch) an easy underhand toss has it flying away nicely. It tracks well, and doesn't seem to have any bad habits. After a few flights, I added a rudder (very easy) and now it's even more fun. The only reason I didn't give it 5 stars all the way is because of the hideous stickers / colors it comes with. Some may like it, but I did not. I removed them and did a simple "Navy Trainer" style scheme with fluorescent red and black vinyl. It looks much better, IMO. :)

Several of our club members have these and we often all fly them at the same. It's a blast! I fly mine on a 3s 1550 but a few fly theirs on 2200s with about 4 min flight times.

My flying field has at least 11 of these airplanes flying at 1 time, It's a great value and fun to fly plane that flies in almost any conditions including high wind. Recommended to anybody especially newbies

The outstanding feature of this plane is the stability from low to high speed. It can really ease down and float by, or confidently zoom fairly fast. Hand launching didn't work very well @ 6400 feet altitude, which is no big shock. The only fault so far is the glue joint near the intakes -- it had almost no glue on it so the nose separated at the first opportunity. But since it's mostly an existing joint, the repair is nearly invisible.

Lighter than the typical jet model these days and that shows up in the flight characteristics. I ding it one point on quality because the glue joint that holds the nose on had almost no glue and the nose broke. Easy fix, though, and it's invisible. The appearance is pretty good but as is usual these days the decals were designed by the same people who did 1980s recreational vehicles, all swoopy and inappropriate. The decals do come off fairly easily, but doing so damages the finish. Hardware has all worked well so far, the hinges are solid, the fit of the screw-on wing is quite good. It's a lot of fun to fly and offers good value.

great packaging making it safe not to get damaged, and fast delivery. I wish the parts would be in stock cause I really love the Jet. I'm new to this and I can only repair it so many times learning to fly for the first time. But I so see the professional care in making the product. Otherwise thanks for your support, and hope to see a chance to order parts soon.

I have been flying for 15 years and also work at a hobby store selling and servicing planes, cars, and trucks. I recently started flying EDF jets, which I found easy and exciting. I have E-flite's 70mm viper and really love the lines and performance. I decided to pick this one up to fly in-between my larger jets while I wait for batteries to charge.

I have flown it on a 3s 1300 mah 30C LiPo pack. I get 5 min flight times, which is respectable for jets. Comparing it to the Eflite 70mm, it has just as good power to weight, going nearly vertical and jumping out of your hand with a light toss. I flew it in heavy winds and it was not thrown around too bad considering its weight and the lack of gyro stabilization on my receiver.

I really wish it had a rudder. I wish it so bad I will be adding a rudder. I know what these servos cost, no reason not to have a rudder. It is also fairly nose heavy, my 1300 mah lipo was positioned near the rear of the tray. Larger batteries would need to go further back, but since they can't it will make it nose down. Adding a rudder and it's servo in the rear will help counter this and also let me enjoy more accurate flying.

It is slippery in the air, though! I found it surprisingly difficult to land, as it just would NOT slow down. The "undercarriage" is thick plastic chunks on the nose and on each wing, mid-span under the servos, and the ventral fin in the rear. The nose is also plastic capped. Seems tough enough for my grass field plops. Flares last a long time and the plane can fly amazingly slow, with great elevator command.

This is a great first jet for a beginner, or a fun time-absorber for an experienced pilot like me. I would absolutely buy again. I wish the canopy was clear, I guess that's my only aesthetic gripe.

To summarize:
+Cheap
+Durable, with plastic where it would likely hit the ground
+Great power
+Stable by design
+Good elevator authority at low speeds
+Good speed for its size
+Low drag
+Relatively long flights, for a jet

-Low drag, landings are shallow in glide slope and grease in, taking a lot of room if you want a low speed touch down.
-No rudder
-CG will not accept large batteries without a lot of trim
-/+Canopy? Black is meh

Would I buy again? Yes. If I ever lose this plane I will buy another. It's fantastic. You should buy it. We need more planes this size. It's a fun and affordable class of EDF.

Diese kleine Viper ist mein kleinster EDF im Hangar. Aber einer (neben der Arrows F-15 twin 64mm) der besten. Die Optik, Lackierung und Schaumqualität ist absolut vorbildlich und kein Vergleich zu Freewing oder E-flite, bei denen die Lackierer teilweise noch viel lernen sollten. Schade, dass Arrows nicht so viele EDF Jet's im Angebot hat... aber das kann sich ja noch ändern, hoffe ich zumindest. :-)
Mein Bruder und mein Cousin haben diesen Jet ebenfalls ein paar Wochen nach dem Vorfliegen von mir gekauft und schon erfolgreich geflogen. Mein Cousin hat der Viper sogar zwei Landescheinwerfer in den Flügel spendiert. Bis jetzt keinen Zwischenfall mit diesen Modellen! BRAVO Arrows!! Vielen Dank für diese schönen und zudem sehr gut fliegenden Jet's.
Grüsse aus der Schweiz.

Talk about bang for the buck!! This lil jet is a blast, and so fast. We put an 1800mah 3S battery in it, it’ll go fast, it’ll slow down decently enough for a comfortable landing….very stable solid flyer. Well worth the purchase and recommend it to anyone wishing to add a smallish EDF to their collection. Fun!!

This is very much my first EDF, I received one damaged clevises, Dan shipped me new ones immediately, did my maiden flight and I feel HAPPY ...it flies great just out of the box, at 3S its ton of fun

This plane is fantastic bang for the buck! Flown it 3s and 4s... seems to handle 4s but doesn't need it! Plenty fast on a 3s 1800mah; we clocked it at 70mph and getting around 6-7 mins of flight time. Build quality is great and it looks and sounds amazing. My first EDF and now I just want more. =) Has a great flight envelop, flies fast and slow. Highly recommended!

All in all this plane is amazingly stable and fun! I’ll just run through my experience so far. Build: was super easy except I’m not very good with glue so it was a little messy. But I think this batch of planes I got had a issue with back screws for the wing, seems like they just didn’t wanna sit right and other people had the same issue. Build overall: very easy! Flying: I used a 2200 3s and I can’t say I recommend a 2200, it flew amazingly other than the super nose heavy part, which lead to no flare at the landing. Flying overall: very stable and instantly got comfortable on the maiden, +super fast! Now a side note, the canopy is surprisingly hard to get off! The magnets are very strong so I just put some clear tape and folded the tape over on itself so I had something to pull on. 

First I want to thank HOBBYZONE for great service , The Viper is a incredible little jet. I am flying it on 1300
30c and 1400 65c batteries . lighter flys better , just balance it and fly, let the edf spool up full throttle and
a under hand toss and your flying. I have a very slight amount of up trim on my first flight. IT flys great at 1/2
throttle and will move very well when you push it to full . G reat flight envelope fast or slow landing is easy.
Four of my club members order vipers after seeing it fly. Simple to build , the foam is smooth and solid foam ,won't dent easy . GREAT FLYING LITTLE JET.

I got this to fly between my larger 70 mm viper flights. It’s tons of fun to buzz around. Flying mine on a 1400 mah 3s gets me 4:30. The 50mm size is a fun one that I don’t see much of, and this viper is a fantastic floaty yet sporty addition to my collection. 

If I totaled it today, I would buy another one immediately. I love it. 

Needs a rudder though. I added a rudder servo just behind the canopy, really lets me slow make turns down low while keeping the wings level. And of course the split-S and hammer heads. Can we start making 4 channel small planes please? Thanks. 

Absolutely love the viper edf. This is my first edf and it has performed better than I could have ever expected! If you are on the fence, buy it! You won't be disappointed.

I put an AR631 Spektrum receiver in this plane for the AS3X and SAFE functionality. All worked well. Very happy with this plane.

The Arrows 50mm Viper is quieter than I thought it would be. On the bench at WOT it doesn't create much noise.
The foam is smooth to the touch and the pieces fit together nicely. Winglets help to create nice stable flight.
The little viper, for now, is quick enough for me.

This is a really fast fun flying aircraft. Easy to hand launch with plenty of power on 3S 2200 The 50mm fan is really efficient and I am getting up to 7 min flight times. It's a quality product and my 1st from Arrows. This Viper is a real smooth flyer and it does track like its on rails. No rudder but I am going to add one soon. Should be easy to do as there is ample room next to the elevator servo to add the servo for the rudder. I recommend this plane to anyone that has a smaller flying area. You won't be disappointed with this aircraft.

It can go as fast as you can handle, and yet it is a docile flyer at lower speeds.

Decided to start flying EDFs, but didn't want to invest a bunch of Benjamins to see if I liked the latest SuperDuperAcroJet and a raft of 6S batteries. I saw the Viper at Hobbyzone, and found it to be a great introductory EDF. It has a broad speed range that is ideal for a first jet, and using 3S batteries means I could test the EDF waters for less than $200.
Assembly is so simple a caveman could do it, and total construction and programming time was a bit over an hour. Simplicity has its benefits. The Viper flies solidly without stabilization and is as responsive as the pilot wishes by programming dual rates accordingly. Not having a rudder means no knife edge flying, but as an inexpensive intro to EDF flying, it's ideal, and a whole lot of fun to fly. The only con is that the strength of the cross sectional area of the fuselage in the area of the intakes is weak, and putting reinforcement in that area is a good idea. I epoxied a 1mm carbon fiber plate to the cockpit floor, and a pair of 4mm x 1mm x 4 inch carbon fiber strips about a half inch below the canopy "rails", which noticeably stiffened the forward fuselage.

This my 2nd viper, 1st one had wing stall ,nonrepairable forward of the wing , so I bought another one. this my 1st edf, and I love flying this plane. its a good 1st edf plane because it is so easy to fly, just toss it and have fun

This little EDF Jet is a riot to fly! Bang for the buck is pretty hard to beat as well. Probably wouldn't suggest that this be your first EDF jet. It's quick and it gets small in a hurry. I had the low rates @ 80% travel & 10% expo, high rates were set @ 100% travel & 10% expo for the maiden using a 4 cell 14.8V 2200 mah 35C Lipo battery and my Spectrum DX6 transmitter. Battery just barely fit and hand launched at about 80% throttle into the slight breeze in my face. The plane rocketed out of my hand and climbed at a good rate until I backed off the throttle and then the nose came down slightly and it leveled into a beautiful slow decent requiring very little trimming at all. Would be fun with some landing gear because the belly landings begin to take a toll. This little jet needs to maintain reasonable air speed when coming in or it will drop like a rock, so nice slow landings aren't really an option. Fine for nicely groomed grass landings or putting it down in the sand by the river, just watch out for large rocks in the sand! I found one the other day and broke the nose off right where the front of the air inlets meets the fuselage. Expected to find a mess but was pleased at how well the craft took the hit! Some foam safe glue and hardener and about a half hours time it was good as new and still flies great after dozens of flights. Could use a rudder, may add one , but the old yank n bank works just fine. Get yourself one, you won't regret it...... well..., until you crash it because odds are eventually you will. lol

The Viper 50mm EDF Jet has the best power an efficiency on a 3S LIPO that I've flown so far.
I fly at 5700' ASL so that does effect lift and power and yet this Jet loved the high altitude.
The stability was rock solid and it performs aerobatic maneuvers with ease.
My favorite EDF Jet so far so keep them coming ;-)

I have many EDF jets and this is my go to when I get to the flying field since it’s so easy to fly and a great way to knock the rust off and calibrate the pilot.  I’m using an AR630 receiver with SAFE and AS3X on a 3 position switch.  Position 0 is SAFE with pitch up at full throttle enabled.  This makes the hand launches uneventful.  Position 1 is SAFE with the pitch change inhibited for just flying around.  Position 2 is for AS3X and makes aerobatics smooth and locked in.  It tracks well and slows down for a slight nose up landing.   Definitely use a 3-minute timer with a 3S 1300 mAh and/or LiPo alarm since it’s easy to loose track of time since it’s so much fun.  It’s a great first EDF and second or third airplane for those wanting to try EDF jets.

Great little jet. Once you get it into the air it is very versatile. It looks and sound great. You can fly slow and keep it in small spaces, or rev it up and do vertical corkscrews. It has a very good roll rate but is also very stable. There is absolutely no need for a gyro to help fly it. The operative phrase here is ‘once you get it into the air’. My success rate for hand launches is running around 25%. It is extremely squirrely right after launching and takes frantic split- second reactions to straighten it out, which takes about 1-2 seconds, after which your Viper is sailing smoothly or in the ground. So far it looks like the best technique it to launch it with a steep right bank so when it snap-rolls to the left you have a half a second longer to correct. It doesn't have enough thrust to fly out of your hand, so it requires a decent toss. My Admiral stability plus receiver didn’t help, in fact it would overcorrect and make things worse. The other critical issue is having the correct CG, which depends a lot on which battery you use. The recommended 1300 MAh goes all the way forward. An 1800 goes further back. Interestingly the 1300 gives a reasonable flight time because it is lighter you don’t have to use as much power.
One thing I did right was to Gorilla -Glue carbon-fiber rods into both sides of the fuselage, which so far has prevented worse damage. I highly recommend doing that for any long nose foam airplane, but I should have started them further back behind the leading edge.
I do recommend this airplane, especially if you have some tall (1 ft+) grass to launch it over, or you know the secret on how to launch these things. Otherwise, you may want to buy a couple extra fuselages to start.

Ordered and got shipping info the same day!
When I opened it everything was great except one of the elevator clevis's was missing, the other it was broken. I contacted HZ and within 48 hours they had shipped out an entire set of replacement control arms and clevises.

Flew with a 3S-2200 Lipo, have to admit I was having so much fun zooming around I didn't manage the throttle very well, so the flight ended way too early.

Initial impression when I unpacked the plane was positive but flying it’s a different matter. I didn’t run the throttle up all the way on first flight which was a mistake. It stalled and turned into a lawn stake. Second flight was better. When setting up, you can’t set CG where battery tray is. I made a new one out of balsa and ran it all the way from front to back in the compartment. This also helps strengthen the fuselage which I could see being frail. The jury is still out on this plane until I fly it more.

The Arrows 50mm Viper is a lot of fun for the size. Today it was flying very well in ten to fifteen MPH winds. It took a few flights to get it trimmed initially and to get to know its character. I now have a switch assigned for three flight modes: Launch, Normal and Landing mode. Launch Mode has some elevator up-trim and Landing Mode is programmed with low rates with a little more expo than the Normal Mode. I have only flown it with a 1.4 Ah 3S Lipo and it does everything I want it too with that battery.

Bought this for the size and 3S battery use as I wanted an EDF I could fly at a small park environment. This plane fits this perfectly. Enough power to hand launch underhand and zip around but stable enough for 1/2 throttle small area flying without stalling. Only negative is the fuselage in front of the wing is susceptible to breaking on a hard nose landing. Some CF reinforcement is a good upgrade in this area. Would buy another if mine wears out.

Great bang for the buck. We have six so far in our club. So much fun to have all in the air at the same time. All have been upgraded to a 4S 40 amp esc with top speed between 95 and 100 mph. Viper flys better and hand launches better than the T-33. Just purchased another one for back up

I think the product is a very good looking and once you get it in the air flies very nice I think for the price it was very good . problem I had was actually hand launching it I found that it was very difficult for me, maybe for others it is not, but I had a hard time doing that

Let’s talk about the pros, it flies good it looks cool it’s cheap, it’s a great first jet. That’s it, that was all from my friends viper that I flew, let’s move to mine. So my impressions were good when it arrived, the gluing was easy and battery bay was big, but the screws for the main wing would not screw in, it took 2 weeks to get this and it will not go together, I’m not about to send it off and get another one after 4 weeks to have the same issue, because other people had the same issue as me.

Maybe it's me...I keep seeing the youtube videos about how easy this plane is to fly, but I cannot get it into the air. I put a Spektrum AR631 AS3X/SAFE receiver in it, and all it wants to do is nosedive. I'm about to give up on it. Before this I bought a Ranger 600mm trainer and it flies great. But no luck with the Viper.