SMALL - espritmodel.com SMALL - Telemetry SMALL - Radio

Think Geek's Tandem Z-1 Chinook R/C Copter RTF Review

Michael Heer has been waiting for the chance to add the Silverlit Tandem Z-1 to his collection of Silverlit helicopters and ThinkGeek had them in three colors on three different bands!

Splash

Introduction

Rotor-spans:5.25"
Weight:23g/
Length:6.75" excluding rotors
Flight Duration:7 minutes
Charge time:10-25 minutes
Transmitter:3 channels for control plus headlight
3-Channel control:Proportional: up/down, rotate rt/lt, forward/stationary
Batteries Transmitter:6-AA 1.5V Alkaline batteries
Range:Up to 30 feet
Two trims:Throttle and left/right
Charger:Built into the transmitter
Manufacturer:Silverlit
Available From:ThinkGeek
Price:$49.99

Since pictures were posted of the Silverlit Tandem Z-1 several months ago, pilots have been waiting for it to be released in America. Stable and controllable, but with traits of its single rotor predecessors and selling at under $50.00, I suspect that ThinkGeek will sell squadrons of them.

Kit Contents

The display box shows a small tandem rotor helicopter painted in a bright civilian color with an infrared transmitter/charger that controls/recharges the copter. There are clear plastic fins on the front and the rear of the copter under the rotor, and the air passing by these fins gives stability to the Tandem Z-1. The rotors are tilted: The forward rotor tilts to the helicopter's right and the rear rotor to its left as shown below.

Supplied in Kit:

  • Tandem Z-1 Chinook style helicopter
  • Transmitter/Charger
  • Spare plastic front vane
  • Instruction manual

Supplied by reviewer:

  • 6-AA 1.5V Alkaline batteries to power transmitter/charger
  • Small Phillips screwdriver

Assembly

I installed the 6-AA batteries that I purchased separately into the Transmitter/Charger. A small Phillips screwdriver was needed to remove and later resecure a screw that holds the battery cover plate in place. That completed the assembly process!

Charging

With the batteries in the charger, I connected the charger to the helicopter via the electrical cord in the transmitter/charger. The length of time it took to charge the helicopter depends on how drained the onboard high capacity Lithium Polymer battery is at the start of the charging process and how drained the batteries in the transmitter/charger are. With new batteries in the charger it only took about ten-fifteen minutes to charge the helicopter. The longest charge took 25 minutes, and that was at the end of this review process when it was probably time to insert new batteries into the charger.

Flying

Infrared Control

The Tandem Z-1 Chinook helicopter is controlled by infrared signals sent by the transmitter. It is necessary to point the top of the transmitter toward the helicopter so that the copter can be bathed in the infrared light. Bright light, especially strong sun light, can drastically limit the range from which the helicopter can receive the signal from the transmitter. An object got between the helicopter and the transmitter's infrared signal when I was flying the Tandem Z-1 and it lost the signal, but it didn't stop operating. It was necessary to get the signal back to the helicopter to regain control. After a few seconds without signal it would stop operating. Sunlight could stop control instantly at times.

The transmitter has three proportional channels and one On/Off channel. Proportional control is to the throttle, left/right and forward. The on/off control is to the light on the bottom of the Tandem Z-1.

Outdoor Coverage

At one Dawn Patrol flying session the air was completely calm. I got out my Z-1 and flew it on the baseball diamond in shade as the sun started to rise. I had good control as long as I stayed in range. But as the sun got higher It shot me down. It can be flown outdoors in complete calm but no direct sunlight.

Downloads

Transmitter Trim Dials

The transmitter has two trim dials: one each in the top corners of the transmitter. The top right trim dial adjusts left and right, and the idea is to adjust it so the helicopter flies forward on the right stick in a straight fashion and doesn't spin left or right unless I direct it to do so with the horizontal right stick. The upper left trim dial is marked forward/backward and it is to set the helicopter so it is neutral movement when throttled up. I had to use a lot of back and left trim in balancing my Tandem Z-1 for neutral movement.

Basics

The left stick has a spring on it that controls vertical lift. The right stick horizontal movement allowed me to turn the helicopter right or left or rotate it in position. The right vertical stick only allowed for neutral movement or forward movement. There was no ability to move the stick to make the helicopter go in reverse. (As mentioned above the left trim tab had forward and backward directions but was rather limited and was designed for trim to get to the neutral movement position.) Double click on the right picture below and see that the stick does not move in the reverse direction.

It immediately becomes apparent that the rear rotor is stationary as to position. It does not move to the side, nor forward or back. The speed of the rotation is controlled (as is the front rotor) by the throttle, but that was the only control I saw on the rear rotor. The rear rotor is mounted at a permanent angle towards the helicopter's left side. The front rotor is angled to the right. It is also tilted by a servo to the left or the right. So it is the front rotor that steers the Tandem Z-1 through the air by use of the right stick on the transmitter.

Flights were started from the floor, desks, tables and right out of my hand by giving up throttle with the left stick. After the Tandem Z-1 was climbing I would ease slowly off the left throttle to get the copter to "hover" and not climb to the ceiling. No matter how softly I eased off the throttle, I sometimes got a hesitation stutter and the Tandem Z-1 would drop. I would apply a bit more throttle and ease off a second time, and it would be in a "Z-1 hover." This was an occasional thing, and I could not reproduce it consistently. It may have been an abnormality for just my copter. Fortunately, it was not a major problem.

The Tandem Z-1 Hover

Only very briefly would the Tandem Z-1 hover in one spot; It usually started to move forward. If I gave a pulse of left it would stop the forward movement, and I would get a slight forward backward movement in the same spacial area that looked like a hover by stopping the forward movement with very brief and often repeated left turn pulses. If I did it too long it would usually end in a slowing of the blades too and a crash. That is what I mean by my "Z-1 Hover."

First Flight

For the first flight I recommend you use the largest space you have available to you indoors. The trim dials can make a huge difference in how the helicopter performs and what direction it goes and how fast it goes there. Mine started like a rocket going forward and to the right. It was making tight right hand circles and required little space for that first short trimming flight. After my first adjustments it was still going forward rather fast and turning right but I used almost all of the space in the ten by ten room. I made a major move on both trim dials and was able to adjust it to a Z-1 hover with some drift during the third flight and I could fly it in a regular size room. Mine gives a very wild flight when out of "trim."

Z Family Flight Characteristics

The original PIcco Zs that I have flown have turned and steered best to the right. Left was a sharper turn and a forward movement stopper, or at least slowed it down. Using left pulses in a quick fashion I could approximate a hover. Each flight was different: Sometimes I had pretty good control and sometimes for no apparent reason it was a fight to control. They were wilder with a full charge on the flight battery and more controllable about half way discharged.

The trim dials on the Tandem Z-1 transmitter do a lot more in adjusting the flight pattern then the trim tabs did on the Picco Z. I found that set up properly I had more control over the Tandem Z-1 then any of the previous helicopters but the family characteristics described above were still present.

Control Explained

With the left dial I could control how fast forward the Z-1 flew without any forward input on the right stick, but I could not get to it just hover no how much I adjusted the trim dials. I could get it to almost hover with certain trim dial settings, but by using the left direction on the right stick and doing it in very short pulses I could obtain what appeared to be almost a hover with slight forward and backward movements keeping it basically in the same area in the room. As with other Zs, right turns were generally broad although via the stick and the dial they could both be made tighter and tighter. The left turns were much tighter than the right turns. Too much left turn signal would usually cause the copter to shudder and crash. You have to fly the Z-1 all the time it is in the air unless you get it into a repeating right circle pattern.

Taking Off and Landing

Takeoff just requires raising the left throttle stick up to about half throttle. All single rotor Picco Zs that I have owned and flown tended to take off in a rolling turn due to torque. I learned that was part of the lift off process, and the same was surprisingly true for the Tandem Z-1 but to a lesser degree because of the tandem rotors. It was more stable than the prior Zs (when properly trimmed) and was able to do the Z-1 hover described above.

Once I had it trimmed for my most near hovering position 90%+ of my takeoffs were as follows: Apply throttle, and the helicopter lifts off and immediately swings to its left and goes forward facing about 150 degrees from the direction faced prior to lift off and out about 3-4 feet from where it started. It stops its forward momentum on its own and backs up about an inch, sometimes three inches, and hovers there briefly and drifts forward. This takeoff pattern occurs repeatedly by just throttling up.

Using the right stick and moving it to either side, the helicopter would rotate in place to the left or the right. Move the right stick forward, and the helicopter will move forward. I was initially able to get it to go backward slightly by adjusting the trim dial slightly, otherwise it could not be directed backwards but it did so slightly on its own as part of its standard take off format. I found the helicopter landed best from a hover with no other directional movement. If you land with much forward movement or especially while turning, the chance the helicopter will tip over during the landing increases.

Special Flight Performance

The handling of the Tandem Z-1 was relatively predictable and controllable, and for a Silverlit helicopter, that handling consistency is unique. I was surprised that there was that much of a learning curve. I had a number of crashes during my first couple of sessions, but fewer and fewer as I adjusted to its handling characteristics. I was soon moving the helicopter around a room primarily by a series of right hand turns and short left hand partial rotations. My control was not perfect, but it was predictable and improved with practice. But a random factor still remained from flight to flight.

The helicopter also has a light in the front bottom of the helicopter. This light is controlled from the transmitter so it can be turned on or off during flight.

Houston We Have a Problem

I had the Tandem Z-1 flying very consistently and was planning to shoot the video. I had the transmitter on a table, and a child picked it up and moved the sticks and the trim trim dials while I was out of the room. The control sticks were returned to their neutral position by the springs attached to them. The trim dials remained where she left them.

I throttled up and there was no rotation. Instead, the Tandem Z-1 lifted off and shot forward like a cannonball, and although I gave a rotate right command it smacked into the window and fell to the ground. The front plastic fin snapped out, and I tried to fly without it. I checked and repositioned the trim tabs, but it was a no go without the front clear trim plastic fin. The Z-1 was spinning on the table top. I reinstalled the fin and was able to take off, but with a little spin to the left. I took off facing about 70 degrees from where it started. I have not been able to get my copter to repeat its original lovely takeoff pattern, and my control has not been quite as good as it was before the crash, but I have gotten it back under control.

Is This For a Beginner?

YES! An adult who can move the control sticks smoothly and slowly can control the Tandem Z-1 after the initial swirl on lift off. With practice, the beginner will be able to move the sticks more smoothly and generally maintain control of the copter. There is a learning curve, but the foam is tough, and mine shows little sign of damage despite many crashes so far. Because of the spinning rotors, anyone flying the helicopter should be mature enough to be aware of the possible danger.

Flight Video/Photo Gallery

Downloads

Conclusion

What an interesting little helicopter! Itís fun to fly a mission or two during commercials on television and recharge while the show is o, and when friends see it they have got to try it. Even with the twin rotors, it shows its familyís flight and handling characteristics.

Pluses:

  • The most controllable of the Silverlit Z helicopters I have flown to date.
  • Price at ThinkGeek seemed very reasonable.
  • Up to three can be flown together.

Minuses

  • Visually the clear plastic fins are a minus but they ARE necessary.
  • Mine sometimes displayed a slight stutter when I eased off on the throttle to level off from a climb.
Last edited by Angela H; Sep 12, 2008 at 10:00 PM..

Discussion

Reply
Thread Tools
Old Sep 13, 2008, 07:57 PM
Registered User
Beaver Dam.Wi.
Joined Jan 2003
309 Posts
have heard the silverlit tandom Z-1 is identical to the air hogs twin thunder.
the twin thunder is available on E-bay for $39.95 and have seen it at target
for a bit more Have seen on another thread they both can be hard to land
because of onely 3 wheels. did you find this a problem?
harrisdouma is offline Find More Posts by harrisdouma
Reply With Quote
Old Sep 13, 2008, 09:34 PM
Registered User
Michael Heer's Avatar
Stockton, Ca. USA
Joined Apr 2001
9,600 Posts
Yes, as stated in the review if moving forward or especialy if turning it is easy to tip over while making a landing. Slow straight descent or just slightly going forward was required for a smooth landing.
Michael Heer is offline Find More Posts by Michael Heer
RCG Plus Member
Old Sep 14, 2008, 01:36 AM
We shall serve the Lord
kingsflyer's Avatar
United States, TX, Kingsland
Joined Sep 2005
5,156 Posts
Nice Review Mike. It looks like it flies a lot like the single rotor Silverlit. I guess I was expecting more stability with the counter rotating blades. It still looks like a lot of fun for the bucks.
Mike McD
kingsflyer is online now Find More Posts by kingsflyer
RCG Plus Member
Latest blog entry: LEDs on my T-28
Reply With Quote
Old Sep 14, 2008, 01:46 AM
**I'm Battman**
RCBABBEL's Avatar
Twin Falls, Idaho
Joined Jan 2005
8,690 Posts
Quote:
Originally Posted by harrisdouma
have heard the silverlit tandom Z-1 is identical to the air hogs twin thunder.
the twin thunder is available on E-bay for $39.95 and have seen it at target
for a bit more Have seen on another thread they both can be hard to land
because of onely 3 wheels. did you find this a problem?

Please show me one on E-Bay for $39.95!!

rc


ps. Excellent review!!
RCBABBEL is online now Find More Posts by RCBABBEL
RCG Plus Member
Reply With Quote
Old Sep 14, 2008, 02:17 AM
CSI
I promise, just ONE more order
CSI's Avatar
Del Rio Intl, Texas, United States
Joined Feb 2004
3,995 Posts
Nice thorough review Mike.
Yes, tip over concerns are valid. This heli is fairly narrow and top heavy, so it likes to topple over. It's not a concern to me because mine stays airborne!

I am sure production tolerances cause some of the flight issues the review model had. I have a Twin Thunder version and it hovers pretty well. Mine has never even had the front clear stabilizer piece on it. Popping the trim ring off from around the right stick on the TX does allow for reverse control inputs, but I do find my heli doesn't really like going backwards to well!

These are pretty nice little helis. I find mine has plenty of control, much more than a Havoc, and really cruises around the house with ease.
Not sure if there is any real differences between the Twin Thunder and the Silverlit versions?
Ken
CSI is offline Find More Posts by CSI
RCG Plus Member
Reply With Quote
Old Sep 14, 2008, 02:40 AM
Registered User
Michael Heer's Avatar
Stockton, Ca. USA
Joined Apr 2001
9,600 Posts
After reading some of the comments I removed the front plastic vane and mine won't fly well with out it. It spins on the table and in the air. I reinstalled the plastic vane and had a very nice flight for the rest of the battery charge. Mike
Michael Heer is offline Find More Posts by Michael Heer
RCG Plus Member
Old Sep 14, 2008, 03:10 AM
Registered User
Beaver Dam.Wi.
Joined Jan 2003
309 Posts
RCBABBEL
I cannot show you a air hogs twin thunder for $39.95 None exist now. I should
have checked before I posted that price. MY error.
Harris
harrisdouma is offline Find More Posts by harrisdouma
Reply With Quote
Old Sep 14, 2008, 04:22 AM
Registered User
USA, WV, Moundsville
Joined Oct 2006
2,779 Posts
FYI the "servo" and i use the term loosely in the front that tilts the rotor on the airhogs one is very weak and prone to stripping we tried a few all ended in the same fate.. small dink into an object.. servo destruction
turbored21 is offline Find More Posts by turbored21
Reply With Quote
Old Sep 14, 2008, 05:27 AM
Beware the Axis of Weasel.
thewildweasel's Avatar
Plymouth, Devon
Joined May 2007
2,475 Posts
You CAN make these helis fly in reverse - there's a shaped piece of plastic, like an inverted 't' around the right stick. This is meant for beginners, but once you have gained control over the heli it just pops off with the tip of a screwdriver, and then the stick can be pulled back. If you look at the photo of the TX on the bottom right above you can clearly see the tabs to left and right of the stick. I must say that the couple I've had goes on wern't as good as I was hoping for, but still a good little heli for the money. BTW, we've got military camo ones in TRU over here now... Nice review, and I like the outdoor flight pics.
thewildweasel is offline Find More Posts by thewildweasel
Reply With Quote
Old Sep 14, 2008, 08:26 AM
Registered User
Pavelow's Avatar
United States, FL, Mary Esther
Joined Jun 2008
276 Posts
I found an airhog twin thunder yesterday at the Salvation Army thrift shop. Took a chance and for $9.99 brought it home. Put in batteries, and it works! Not very stable, but I now know (thanks to your review) that it is missing the front clear plastic fin. Thanks.
Pavelow is offline Find More Posts by Pavelow
Reply With Quote
Old Sep 15, 2008, 04:15 PM
Registered User
Michael Heer's Avatar
Stockton, Ca. USA
Joined Apr 2001
9,600 Posts
Check out the miracle berry pills at Think Geek when you go to investigate the helicopter. They are pricy at $20.00 for 10 pills but you cut each pill in half so it is twenty servings. Line up a variety of food items especially some sour and bitter items as well as a few sweets including some bitter dark chocolate and a few other items like limes and lemons and other fruit. Dissolve 1/2 a pill on your tongue and try the various food items. It is pretty wild and was really surprising to me when I tried one for the first time. I have ordered several boxes to give as Christmas presents. I wouldn't mention it here as it is obviously off topic except they really are very different and fun to try. So if you are going over to Think Geek check them out while you are there. It only lasts on me about 1/2 hour but for some up to an hour. I have no financial interest in Think Geek, I just thought I would share an interesting off topic item for those that might be going there any way. Oh if you drink wine or beer be sure to have some handy to try out as well. Mike
Michael Heer is offline Find More Posts by Michael Heer
RCG Plus Member
Old Sep 16, 2008, 09:59 AM
Registered User
Michael Heer's Avatar
Stockton, Ca. USA
Joined Apr 2001
9,600 Posts
Review Update

Three Important pieces of information learned since I posted this review.

1) TheWildWeasel was 100% correct. The disc on the gimbal that prevent me from moving the stick down and flying backwards was removable. I have removed it from mine and I can now fly backwards with mine.

2) I saw a Bay Area friend over the weekend who bought a Tandem Z-1 from ThinkGeek and we flew together indoors over the weekend. His did real hoover and was more precise in its handling then mine. This was true whether he was flying it or I was flying it. So it was the copter and not our thumbs that was responsible. I initially had no explination for the difference at that time. (He still had his antibackwards disk on the right gimbal and after we removed that his flew backwards very nicely as well.) His still had his front fin on and I didn't think to try flying without it in place. It did have what I describe as the Picco Z family traits on start up but within a second was under good control.

3) Someone close to Silverlit has since advised me that I may have gotten one of the very early models made for my review. The very early models didn't fly well without the forward fin, and that describes mine. Since those first models they have improved the Tandem Z-1 so that it flies well without the front fin and has improved handling and stabilization and performs a true hover and goes more precisely where directed. This was done by improving the mechanics inside the copter. I was further told that those early models are all gone and that buyers shouldn't worry about finding them out in the current stock at any store.

The information in number 3 explained what we observed in the differences in handling between my Tandem Z-1 and my friends Tandem Z-1. It also explained a couple of e-mails sent to me from Tandem Z-1 owners who said their Tandem Z-1s flew better then mine and as one said maybe I had dumb thumbs.

While I may have dumb thumbs as one reader said; I conclude from the information received from several sources and observed in my friends Tandem Z-1, purchased from Think Geek the following. The Tandem Z-1s currently in stock will most likely do a true hoover with minor stick adjustments needed (it was not hands off). Will fly fine without the forward fin but probably still better with it in place. Will very very likely fly better then mine with hoover and more precise control.

I can't afford to buy half a dozen to confirm my conclusions. So I request that those of you who buy a Tandem Z-1 to post here after you have been flying it for a couple of weeks and report your findings on flight without forward fin, real hoover and directional control. I'm asking you to all be follow-up reviewers on this project. Michael Heer
Michael Heer is offline Find More Posts by Michael Heer
RCG Plus Member
Last edited by Michael Heer; Sep 16, 2008 at 01:38 PM.
Reply With Quote
Old Sep 16, 2008, 10:38 AM
Registered User
Zurich
Joined Apr 2006
3,989 Posts
For REAL (tight!) control, at nearly hobby-grade level

See my "tricks" in ALL my posts in the Micro RTF "Twin Thunder" thread .... Lee
xlcrlee is online now Find More Posts by xlcrlee
Reply With Quote
Old Sep 19, 2008, 08:50 AM
Registered User
Zurich
Joined Apr 2006
3,989 Posts
.... especially about physical trim trix for true hover, controlled-hover (like large hobby heli!) practice up close, and smooth no-tip landings.
xlcrlee is online now Find More Posts by xlcrlee
Reply With Quote
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Article Think Geek's Dueling Space Marines Copter Set Review Michael Heer RC Toys 14 Oct 29, 2008 09:48 AM
What's the best fully R/C 1/2A engine? thrashaero Engines 1 Jan 07, 2003 08:26 PM
Guillow's Spitfire as electric R/C Clipperkite Beginner Training Area (Aircraft-Electric) 23 Mar 11, 2002 11:39 AM