Horizon Hobby Hangar 9 Van's RV-4 30cc - RCGroups Review

Horizon Hobby Master Designer Ali Machinchy has created a Giant Scale RV-4 ARF for Hangar9. Join Mike McDougall as he tackles the build and then wrings out the RV-4. Let's see if Ali has captured the full scale RV-4's legendary gentle flight characteristics as well as its nimble aerobatic capabilities.



Hangar 9 Van's RV-4
Wingspan:85.0 in
Length:73.0 in
Wing Area:1551.0 sq in
Weight:17 to19 lbs
Wing Loading:25.3 oz/sq ft
Servos:(7-8) Standard Size
Radio:Minimum 6 Channel DSMX/DSM2
Battery:5000 mAh 10S LiPo
Motor:160 BL Outrunner 245 kV
Prop:18x10 2- blade
Transmitter:Spektrum Dx18 G2
Manufacturer:Hangar 9
Available From:Horizon Hobby through your local hobby shop
Street Price:$449.99

The full scale Van's Aircraft RV-4 first flew in 1979 and was a two-place redesign of the very popular RV-3. The RV-4 went on to become one of the most popular homebuilt aircraft in the world. There were many reasons for the design's success, but high on the list was the big grin owners got from flying such a nimble and adaptable airplane. The RV-4's cruise speed allowed comfortable cross country junkets, its slow-flight characteristics allowed back country access, and its responsive controls allowed sport aerobatic maneuverability. What's not to like about the RV-4.

Hangar 9 master model designer Ali Machinchy took on the Herculean task of trying to capture all that RV-4 magic in a giant scale model that would give us that same big RV grin. His newest 85" 30cc Class masterpiece combines ARF building ease with gas/glow/electric power options that will give more modelers easy access to an exciting giant scale modeling experience.

First Impressions

My first impression was WOW that's a BIG Box! When I finally wrestled it into the house, I was able to get it opened and started unpacking all the parts. The covering job looked great and the flying surfaces were all pre-hinged in a very scale-like manner. The fuselage hatch was nice and roomy and the included cockpit details and scale pilot were a nice touch. The paint of the fiberglass parts closely matched the UltraCote covering colors and had nice sharp paint lines. The landing gear and the 4" metal-backed Spinner looked mighty sturdy. The huge canopy didn't require any trimming and it and was crystal clear.

Kit Contents

Here's a list of the parts:

  • Balsa and plywood airframe with UltraCote covering
  • Fuselage with large battery/tank hatch
  • 2-Piece wing with ailerons and flaps hinged and installed
  • 2-Piece horizontal stab with elevators hinged and installed
  • Vertical stab with rudder hinged and installed
  • Aluminum wing and stab tubes
  • Sturdy metal landing gear with painted fiberglass fairings
  • Painted fiberglass cowl
  • Cockpit interior and scale pilot figure
  • Huge clear canopy
  • Metal-backed 4" Spinner
  • LED landing lights
  • Decal sheet
  • Complete hardware package
  • 27-Page illustrated Instruction Manual

Required Parts

  • Minimum 6-channel transmitter and receiver with 7 servos (8 for gas or glow)
  • Power 160 brushless outrunner motor, 245kV
  • 10S 30C Lipo Battery - 5000 mAh
  • 120 Amp brushless ESC
  • Two 1.5" servo arms
  • One 3" double servo arm
  • Four 9" servo extensions
  • Two 18" servo extensions
  • CA and canopy glue
  • Common building tools

Parts Supplied by Horizon for this Review

For this review, Horizon Hobby supplied an E-flite Power 160 motor, two E-flite 5S 5000 mah 30C Lipo batteries, a Castle Creations Talon 120 ESC, a Spektrum AR9350 9-channel receiver, and seven Spektrum A6180 servos with servo arms and extensions.


The 27-page illustrated Instruction Manual details the assembly process for the RV-4. It's filled with excellent step-by-step instructions and detailed pictures to guide the builder through the entire process. There were a couple of errors in the original instruction manual. Most of the errors have already been corrected in the Online version and the hard copy manual should be corrected in the next run of kits. I'll document the needed corrections and hopefully point out a couple of helpful hints along the way.


The first tip would be to select and install your preferred trim scheme decals before starting the actual build. The wing and fuselage were much easier to handle right out of the box than they would have been later in the assembly process.

The kit contained enough decals to complete three different trim schemes. There were two sets of side numbers for a nice homebuilt look, and a very colorful set of stars & bars for a pseudo-military trim scheme. I've always been a sucker for stars and bars, so I chose the military decals.


The assembly process began on Page 11 with the wing servos. The first order of business was locating and opening the servo cover mounting holes and drilling the mounting holes for all the covers. It was helpful to mark each cover as to its orientation and servo function as soon as it was removed from the wing. The card stock from the liners in the servo boxes made perfect shims for getting the servos correctly spaced away from the covers. Once the servos were screwed in place, the shims were removed leaving the servos properly vibration isolated from the covers.

Each aileron servo needed a heavy-duty 18" servo extension. The original manual called for the 18" extensions, but since they were listed under the Optional Items heading in the manual rather than the Required Radio Equipment heading, they could have been missed when ordering materials.

In addition, the aileron servos needed 1-1/2" servo arms and the flaps needed 13/16" arms for proper surface throws. The recommended Hanger 9 aluminum arms were perfect for the ailerons, but the standard Spectrum servo arms were not long enough for the flaps. Luckily there were some longer heavy-duty servo arms available as a set from Horizon that worked well for the flaps.

There was also some confusion about the fiberglass control horns for the flying surfaces. There were two different lengths and two different colors supplied with the kit. The shorter control horns were for the ailerons, flaps, and elevators. The two longer horns were for the rudder. The confusion came about due to an error in painting the control horns. The two short horns for the elevator were painted blue instead of white and the two longer horns for the rudder were painted white instead of blue. Hopefully this error will be corrected in the next run of kits.

Once all the servo linkages were installed and adjusted, the flap linkage covers were glued in place. The covers needed to be opened up a little and centered over the openings for the clevis and its keeper to properly clear throughout its full range of travel.

The LED landing lights did not have any connectors so I soldered on a couple of servo extensions. Since the LEDs were rated for 6 to 12 Volts, I decided to use a 3-cell 850 mAh Lipo battery for power. The On/Off function was controlled by an optical ignition kill switch. The switch was controlled through a "Y-harness" connected to the right flap lead so that the lights came "ON" whenever the flaps were deployed.


Next up was the fuselage. Unlike many ARFS, the RV-4 fuselage assembly started with the receiver and servo installations. The receiver location was dictated by the power choice of gas/glow or electric, and the servos needed to be centered and set up prior to the surface installations. Since the Review RV-4 was to be electric powered, the receiver wiring needed to be routed through the opening on the right side of the fuselage. The battery tray mounting bolt needed to be shortened to 3/4" and the front edges of the tray tab needed to be rounded a bit for easier insertion into its mounting slot.

The manual called for the rudder and elevator servos to be installed with their output shafts facing the front of the fuselage. However, with the rudder servo facing forward, the 3" double servo arm would hit both of the elevator servo output shafts. Horizon recommended shortening the rudder arm to provide the needed clearance. I chose to mount the rudder servo facing the tail instead so I could use the full 3" length of the arm and get maximum rudder throw. Even with the rudder servo mounted toward the tail, the heavy-duty elevator servo output arms needed to have their outer perimeter trimmed just a bit for the rudder arm to clear.

The rudder and elevator assemblies were next on the list. Even though the control horn colors didn't match the surfaces, the short control horns were installed in the elevators and the long control horns were installed in the rudder.

The elevators easily bolted into place with 8-32 x 3/4inch socket head cap screws. The original manual called to drill a hole in the rudder 4-5/8" behind the hinge line to mount the tail wheel steering assembly. The correct dimension should have been 2-1/4" behind the hinge line.

Coffee Stir Sticks made perfect antenna keepers for the main antennas and great antenna protectors for the remotes. I added longer remote receiver extensions to allow the two remote receivers to be mounted farther back in the fuselage.

The wheels and optional fiberglass gear covers were next. I was on the fence for a while, but finally decided to install the fiberglass gear covers and fairings. The fairings needed to be taped up and out of the way during the installation of the wheels and wheel pants. The fairings were then slid back in place to be glued to the fuselage and wheel pants. The gear covers turned out to be well worth the effort. They look fantastic!

Next step was the motor and ESC. The motor box required some final assembly and reinforcing but it turned out mighty sturdy. I mounted the ESC on the right side of the box so that it could get better cooling airflow from the cowl cheek air inlet. A couple of baffles were installed inside the cowl to better direct the cooling airflow. The left cheek baffle was sharply angled to direct the airflow over the motor and the right baffle was installed with a shallow angel to direct the airflow back over the ESC. The lower cowl inlet was plugged to force more air through the upper cheek cowl inlets.

The actual cowling installation on the fuselage turned out to be a bit tedious. Because the cowl was so large, it was difficult to keep aligned and centered on the motor shaft. A 1/8" thick cardboard spacer was cut out using the spinner back plate and washer as a template. With the cardboard spacer in place, and the spinner back plate bolted down, the cowling was easily centered and properly spaced back behind the spinner.

AS3X Programming

The next step was to decide on whether to utilize the AS3X stabilization feature on the Spectrum AR9350 receiver. I have to admit that I enjoy flying AS3X on UMX models, SAFE/SAFE Select models, and even the larger Carbon-Z T-28. Since I wasn't sure if the 30% scale RV-4 was going to be stable or a handful, the AS3X stabilization seemed like a very good idea.

Luckily there was an excellent thread here on RCGroups that dealt with these receivers and there were a series of 13 YouTube videos from Horizon that took me through the complete programming process.

In the end, the three flight modes were set as FM1 Moderate Gain (60-70%), FM2 Mild Gain (35-40%) and FM3 Zero Gain. These settings were chosen for gusty/windy conditions, normal conditions, and " I'm going to do this myself" conditions.


The completed RV-4 weighed 18 lbs 8 ounces, with the two 5S 5000 mAh batteries, RTF. The plane balanced perfectly at 6" back from the leading edge of the wing with the batteries installed toward the back of the battery tray.

The control surface throws were set to the following recommended amounts:

  • Ailerons - +50/-40mm 3D Rates, +42/-34mm High Rates, +27/-22mm Low Rates
  • Elevators - +40/-25mm 3D Rates, +34/-21mm High Rates, +22/-14mm Low Rates
  • Rudder - +/-55mm 3D Rates, +/-47mm High Rates, +/-30mm Low Rates
  • Flaps - 140mm Landing Flaps, 25mm Mid Flaps

The transmitter countdown timer was set for 7 minutes and set to start and run at any throttle setting above 20%.

Preflight Overview

After all the hard work was done, it was time to step back and take a long loving look at the finished RV-4.

Hangar 9 Van's RV-4 30cc - RCGroups Pre-Flight Review (4 min 43 sec)


The Hangar 9 RV-4 is a giant scale model of a great flying homebuilt. To remain true to is full scale heritage, the model should exhibit stable low speed capabilities as well as sparkling aerobatic maneuverability. It's time to ignore the butterflies and shove the throttle stick forward and see how this RV-4 flies.

Taking Off and Landing

AS3X was set to FM2, flaps were left up, and the throttle slowly advanced. The rudder was responsive as the tail lifted and the plane tracked well down the runway with just a hint of right rudder to keep it centered. The wheels broke ground before half throttle and the RV-4 climbed out rock steady as the throttle was eased on up. Subsequent takeoffs were just as uneventful with or without the AS3X. The RV-4 had excellent ground handling manners.

Landings for most giant scale planes usually work best with a little power carried into the final approach. The RV-4 was no exception. Just a bit of power kept the approach angle steady all the way to touchdown. Wheel landings were so easy and they looked very scale. Rollout was pretty long on our runway, so a shallow approach was needed to allow enough room to slow down and turn out. Mid position flaps helped slow down the approach speed and shortened the rollout distance. Full flaps were very effective. The approach speed was reduced even further and the rollout was much shorter. I don't know if the credit goes to Van's original design, or to Hangar 9, but this RV-4 lands like a dream.

Scale Flight

There's just something special about a giant scale model in the air. This Hangar 9 RV-4 looked almost real as it moved around the pattern. This model flew so well and felt so steady that it gave this pilot heaps of confidence right from the start. The RV-4 felt responsive, but never touchy. Even when it was slowed way down, it still flew rock solid. When forced into a stall, the nose fell through and the plane started flying almost immediately. There was no hint of dropping a wing, or snapping. Mid flaps and full flaps didn't require any elevator compensation to maintain level flight. Low and slow full flap passes were things of beauty and sure impressed the flyers in the pit area. The LED landing lights also added a lot to the scale realism.


Most giant scale models of homebuilts are not known for their great aerobatic capabilities. Luckily for us, the full scale RV-4 was designed as a sport aerobatic airplane. The Hanger 9 model followed in those footsteps and was able to easily perform all the typical sport model aerobatic maneuvers. The rudder was very effective. Stall turns were nice and crisp, snaps were quick and tight, and knife edge flight only required 1/4 rudder deflection. The elevator was just as effective. Even at mid rates, loops were very tight both inside and outside. Spins were nice and tight and recovery was quick and easy. The Power 160 had plenty of power on 10S and only needed full power for extended verticals or just for showing off fast and low.

Is This For a Beginner?

Giant scale models are not for the absolute beginner. However, the Hangar 9 RV-4 would be the perfect first giant scale model for any intermediate flyer. It's a real tribute to Ali Machinchy's design abilities that this model is so stable and forgiving.

Flight Photo Gallery

The Texas weather wasn't cooperating, but it was time for the RV-4 maiden, so we packed up the cameras and headed to the flying field. Dreary skies and a light wind, don't make for very good photography, but it's not too bad for flying. The flight batteries were installed, the Nikon was at the ready, and Jesse Webb was in position. Hope you enjoy the results.

Flight Video

Jesse Webb was manning the Camcorder for our video and the RV-4 was in the air in no time. He did a great job of capturing the whole flight, even the part where he documented the back of my bald head.

Hangar 9 Van's RV-4 30cc - RCGroups Flight Review (9 min 10 sec)

Final Thoughts

This new Hangar 9 Van's RV-4 is a real sweetheart. This giant scale model has all the killer good looks of the full-scale RV-4, but it flies like an intermediate sport plane. Ali Machinchy and Hangar 9 have somehow distilled the iconic gentle flying traits of the full-scale Van's RV-4 into this giant scale ARF. When I got home, I double checked through the whole Instruction Manual and nowhere could I find it listed, but this Hangar 9 RV-4 definitely included a generous, full scale "RV Grin". I bet every RV-4 kit includes one. Let me know when you get yours.


  • Superb Scale Details
  • Gas/Glow/Electric Power Options Supported
  • Two-piece Plugin Wings and Horizontal Stabs
  • Flying Surfaces with Scale Hinges Installed
  • Effective Scale Flaps
  • Attractive Gear Covers
  • Bright LED Landing Lights
  • Huge Canopy
  • Generous Hatch
  • Detailed Cockpit Interior
  • Scale Pilot Figure Included
  • Gentle General Flight Characteristics
  • Nimble Aerobatic Capabilities


  • Errors in the Manual

RCGroups.com Review Policies

Our intent is to provide fair and unbiased reviews so that consumers can make informed decisions regarding new products. Some things you should know about our review process:

  • RCGroups.com review items are provided by hobby manufacturers and suppliers, some of whom may be RCGroups advertisers.
  • Review products are sent directly to independent reviewers, chosen by RCGroups.com.
  • RCGroups.com reviewers are not compensated by either RCGroups.com or the reviewed item's supplier. However, they are allowed to keep the review items at no charge.
  • Published reviews reflect the opinion of the author.
  • When a conflict arises between a review sponsor and a reviewer (which is rare), RCGroups attempts to work out a satisfactory solution for all parties. In some cases, this may mean that a finished review will go unpublished, or be subjected to editing for technical accuracy.
  • RCGroups reserves the final say as to whether an article is fit for publication.

It is always our intent to provide a place for honest and open commentary, and to put the needs of our visitors first. If you feel that something we've published is inaccurate, please let us know using the contact form.

Last edited by Matt Gunn; Nov 22, 2017 at 01:25 PM..
Thread Tools
Dec 12, 2017, 06:41 PM
We shall serve the Lord
kingsflyer's Avatar
Thread OP
I'm liking this plane more and more every time I fly it!

Latest blog entry: LEDs on my T-28
Dec 12, 2017, 08:20 PM
Registered User
Fentonflyers's Avatar
Nice plane. Nice review. Wish sometimes I didn't have so many planes, or at least maybe a wife that didn't demand my planes don't migrate into the living areas of our home. Still can't see the harm in hanging a few in the great room...
Dec 12, 2017, 10:02 PM
Registered User
marksp's Avatar
Great review!

The areas I spent hours scratching my head (control horns, tail wheel, rudder servo) are well documented which should be of great help for those who have yet to build.

Latest blog entry: Hangar 9 XCub 60cc
Dec 13, 2017, 03:22 PM
Registered User
aec III's Avatar
Nice review and good photos. Lucky for me it won't fit in my escape.
Dec 13, 2017, 08:11 PM
One more flight...
CashD's Avatar
Originally Posted by aec III
Nice review and good photos. Lucky for me it won't fit in my escape.
Or...you could get a new vehicle in a matching color...
Dec 14, 2017, 08:47 AM
Everything RC
flypilot's Avatar
Love my RV-4 as well, here is mine with a Saito FG57 and mufflers ... I used a 6 volt to 12 volt steup-up regulator to power my landing lights of my receiver pack, also put an electronic swith on them to be able to control them with a switch.

Link to the stepup regulator I bought : https://www.ebay.com/itm/DC-3-3V-3-7...72.m2749.l2649

Some flight video:

Hangar 9 30cc RV-4 and Saito 57Ts (4 min 0 sec)
Dec 14, 2017, 09:44 AM
We shall serve the Lord
kingsflyer's Avatar
Thread OP
Thanks for the Kudos guys.

flypilot, I watched your video before I even started my build and I was impressed by the overall flight characteristics of this RV-4. The Review electric version may not have the same power-to-weight ratio of your model, but it sure has the same great flying qualities. This has to be one of the sweetest landing models I've flown in a long time.

I like your idea of using a voltage booster for the landing lights. I'm sure it would work just as well for an electric powered version and would eliminate the need for an extra battery.

Latest blog entry: LEDs on my T-28
Dec 16, 2017, 01:13 AM
Official Boat Bum
Eddie P's Avatar
She flies so nice! Thanks for the review.
Dec 26, 2017, 09:07 PM
Builder of flying things
fyrechaser's Avatar
Great review Mike! Love that airplane.....
Jim B.

(wish I had one)
Last edited by fyrechaser; Dec 26, 2017 at 09:15 PM.
Dec 27, 2017, 12:24 PM
We shall serve the Lord
kingsflyer's Avatar
Thread OP
Glad you like it. Come on over to SEFF this year and I'll give you a pull on the sticks.

WARNING: Anyone flying this model will want to buy one ASAP. You've been advised!

Last edited by kingsflyer; Dec 31, 2017 at 11:59 AM.
Feb 07, 2018, 11:05 AM
"the analog man"


Guys, Any chance the VVRC 40cc twin Gen2 would fit nicely into the cowled front of the RV4? The photos make the front end look quite narrow?

Larry Fitch
Feb 07, 2018, 11:30 AM
We shall serve the Lord
kingsflyer's Avatar
Thread OP
There have been a lot of folks asking that very question. I'm pretty sure the motor itself would fit within the cowl, but I think the issue is going to be with the mufflers. The muffler cans stick down from the motor and would require cutting the cowl out on the bottom. Maybe someone who has a 40cc twin in their RV-4 could take a picture and post it here on the thread for us.

Latest blog entry: LEDs on my T-28
Feb 07, 2018, 08:32 PM
Registered User
marksp's Avatar
I’ve got the VVRC Gen2 engine fitted. Not wanting the hack cowl, I’m using the VVRC 2:1 header with the MKS 75mm canister. Engine fits completely inside of cowl.

I’m on the road through end of week, so no pics, but i’ll get some pics posted this weekend
Latest blog entry: Hangar 9 XCub 60cc
Feb 08, 2018, 12:05 AM
"the analog man"

Mark, Thanks

I really look forward to your photos!

Larry Fitch

Quick Reply

Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
New Product Hangar 9 Van's RV-4 30cc ARF 85" Bajora Giant Electric Planes 302 Mar 27, 2019 06:51 AM
Article Hangar 9 Van's RV-4 30cc ARF 85" Jason Cole Joe Nall 2017 5 Mar 22, 2019 08:59 PM
Discussion Hobbyking Van's RV-4, 1600mm Diesel6401 Sport Planes 27 Jul 06, 2015 09:28 AM
Build Log Van's RV-4 HobbyKing ARF Riffo Fuel Plane Talk 13 Apr 28, 2015 10:43 PM
Build Log 1/4 scale Vans RV-9 from 4 sheets depron RJPIoW Foamies (Scratchbuilt) 29 Jun 30, 2014 01:46 PM