Orbx Van's RV-4
For FSX / Prepar3D Published by Orbx
Reviewed by Andrew Godden
May 2014

In the future, the late 20th century could be labelled the era of the homebuilt aircraft, an era which could stand on its own next to others in aviation history. The emergence of a raft of affordable designs during this time and into the 21st century has put flying well and truly in the easy reach of the average person. From the simple to the more complex composite construction aircraft with glass cockpits, homebuilt aircraft have come of age.

Orbx, more renowned for their global, regional, and airport series of scenery add-ons for flight FSX and Prepar3D, have previously released an aircraft, the Lancair IV-P. They have now added to this with the Van's RV-4. A popular aircraft in the homebuilt market, it is a compact, sleek and sporty aircraft with good cross-country capabilities.


The Van's RV-4 is a two seat, tandem configuration, single engine, homebuilt aircraft with a low cantilever wing and a conventional landing gear. The second most popular in the RV range, the RV-4 was developed from the Van's RV-3 and is designed for sport aerobatics. More than just a stretch of the RV-3, the RV-4 has also proven to be very capable cross-country aircraft.

Availability and Installation

The Orbx Van's RV-4 is currently available direct from The FlightSim Store as a 'download only' product (a master back-up CD / DVD service is also offered for a minor additional cost). It is priced at AUD$35.95, or the equivalent on currency cross rates. The file size of 259.78MB may seem large, however, it is reasonable for an aircraft of this type and quality and detail it requires 1.14GB of HDD space for installation. A ‘Registration Key' is issued to be used during installation.


There are two manuals provided in Adobe Acrobat format (.pdf):
    ●  User Manual – this 76 page manual provides a comprehensive guide to the aircraft, instruments, and systems; and
    ●  Pilot Operating Handbook – this 43 page document details the operating limitations, weight and balance information, performance,
        normal procedures, emergency procedures, and other aspects of the aircraft.

These documents are extremely comprehensive and are deserving of some attention at some point in order to get the most out of flying the Van's RV-4.

There were some very notable variances in the aircraft performance and specification data provided in the Pilot Operating Handbook with that on the Van's Aircraft web site. In some instances, e.g. fuel capacity, this also varied to what is modelled in the aircraft.

Model Features

The Orbx Van's RV-4 is modelled on a real world aircraft, VH-PTT, and is equipped with an Advanced Flight Systems EFIS. The developer, Jared Charalambous, has modelled the aircraft and systems very nicely. As a sport aerobatics aircraft, the RV-4 can be unforgiving, but once mastered, it is a joy to fly. This review has involved over 20 hours of specific flight testing flying hours and it is evident Jared has delivered an aircraft which accurately reproduces the features and flight characteristics of the Van's RV-4.

The major model features listed for the Orbx Van's RV-4 include:
    ●  high detail VC with specular occlusion modelled in 3dsMax;
    ●  fully functional systems and faithfully reproduced instruments, including a complete Advance Flight Systems AF-3500, multi page EFIS;
    ●  in-simulator engine, electrical, and systems maintenance interface with integrated cumulative physics engine;
    ●  high definition liveries; and
    ●  support for RealityXP with 3D geometry.

There is a single model provided (one pilot), 11 HD paint schemes and a paint kit provided for aircraft painting enthusiasts.

General Visual Appearance

Exterior. Orbx's Van's RV-4 displays a high level of attention to accuracy and detail. A comparative review of photographs of VH-PTT, the real world aircraft on which it is modelled, reveal the exterior shape and dimensions to be highly accurate and a true representation of the real world aircraft.

Interior. Consistent with the exterior, the general appearance of the cockpit and the panel layout are also modelled to a very high degree of detail. Being a homebuilt aircraft, and based on a specific real world aircraft, the avionics layout and fit out of Orbx's Van's RV-4 varies widely from the layout of other researched real world RV-4s and displays a modern appearance with the inclusion of the Advanced Flight Systems AF-3500 EFIS. Nonetheless, when compared to real world photographs of VH-PTT and similar layouts, the cockpit and panel layout are modelled to a high degree of accuracy.

Paint Schemes. There are 11 individual paint schemes (a selection only shown below) provided with the Orbx Van's RV-4 and each aircraft has a unique aircraft registration number. Some of these are absolutely stunning with highly detailed airbrushed style designs and the surface textures, reflections, and shadings give the aircraft a beautiful crisp and realistic appearance.


The exterior modelling accuracy of the Van's RV-4 is excellent. The level of this detail includes wheel fairings, individual fuselage panels and panel rivets, an access panel, aerials and antenna, and fuel tank caps, and all adding to the overall realistic appearance.


The rendering of the cockpit of the Van's RV-4 is very good and realistic when compared to real world layouts.

Instrument Panel Layout. The Advance Flight Systems AF-3500 EFIS sits centrally on the panel with secondary flight instruments to the left of this unit. To the right of the EFIS main unit, is a Garmin GNS 430 GPS unit and Garmin GTX 327 digital transponder unit. The GNS 430 provides for tuning of the COM and NAV radios. The Advance Flight Systems autopilot unit is a two axis unit and is located to the right of the transponder unit. The throttle controls are all located to the pilots left side and the light switches are located to the pilots right side. The yoke is a centre stick type and has 'hat' style trim controls located on it and the fuel tank selector is located on the floor, forward of the yoke stick. All secondary flight instruments are clear and easy to read but the Advance Flight Systems EFIS sometimes requires a higher level of view zoom to see the detail clearly. Various alternative cockpit camera views are available to provide more detailed views of the instruments, however, there are no checklists or aircraft reference data provided on the 'Kneeboard'.

Advance Flight Systems AF-3500 EFIS. The Advance Flight Systems AF-3500 EFIS is rather complex, particularly if you are not familiar with this type of system. The User Manual covers the operations of the unit in high detail and a thorough read of the manual is warranted. Even after all of the flight testing for this review, there are aspects of the operation of the AF-3500 I am still coming to grips with.

Cockpit Layout. Being a homebuilt aircraft, the cockpit layout of Van's RV-4 is best described as basic. With its tandem seating arrangement, the pilot sits in the front seat and the passenger in the rear seat. There are no flights controls or instruments in the rear seat. There is various piping, cabling, and ducting portrayed and combined with the textures of the seating and seatbelt webbing, they provide a good and reasonably realistic appearance.

Overall though, the attention to detail on the interior is, again, of a high quality.


The animations of the primary and secondary control surfaces and other moving elements on the Orbx Van's RV-4 are all modelled faithfully.

Animations include:
    ●  primary control surfaces – ailerons, elevators and rudder;
    ●  secondary control surfaces – flaps; and
    ●  others – elevator trim tabs, rolling wheels, cockpit canopy open / close.


A credible job on the lighting and lighting effects has been done on the Van's RV-4 and they provide a good, realistic representation of the real world aircraft. There is the usual navigation lights, strobe lights, landing light, and panel lighting. Other than the landing lights illuminating the ground effectively, the strobe lights also provide this illuminating effect. The detailed night light effects for the instrument panel, generally, are good and replicate the night lighting seen in photographs of real world aircraft.


The Van's RV-4 is equipped with a Lycoming O-320, four cylinder engine, the sound of which has been represented quite nicely. From initial start-up, through idle to full power and cruise power, the sounds exhibit a deep throaty thrum and seem a realistic representation of the real world sounds. As usual, there is also the normal array of sounds associated with switches.

General Characteristics and Performance Specifications

The general characteristics and performance specifications for the Van's RV-4 are provided in the table. This is based on data from the Van's Aircraft web site, data in the aircraft details provided by Orbx, and general research sources. Some of this data varies between sources and also may be an approximation due to variances in data and the specific aircraft modelled by Orbx.

Flight Performance

Flight testing was conducted in clear weather with a full fuel load and the aircraft at maximum take-off weight (MTOW). Like most aircraft of this type, adjustments must be made to fuel / pax loading to remain within the MTOW limitations.

A cruise altitude of 8,000 feet was adopted on the Test Flight. During cruise, a manifold pressure setting of 19.0 inHg, an rpm setting of 2300 rpm and a mixture setting to produce a fuel flow rate of approximately 5.2 gph were established to produce the published 55% power setting for maximum endurance performance. This cruise setting produced an average speed of approximately 129 knots true air speed (KTAS). However, using the performance settings from the manual, and even with various minor adjustments, I was unable to match the endurance consistent with the specified range characteristics of the aircraft. This variance was between approximately 13%, using a 50% power setting, and up to 25%, using the published 55% power setting. I was also unable to match the specified cruise speed for the aircraft. The Test Flight confirms there are significant inconsistencies in the modelling of the aircraft for range performance and speed.

The aircraft uses differential braking for steering during taxiing, and once mastered, is relatively easy to taxi. With 0° flaps, aircraft rotation occurred at approximately 55 to 60 knots indicated air speed (KIAS) and the aircraft easily maintained a normal climb speed of approximately 113 KIAS at a rate of climb of 1,000 ft/min. Even at MTOW, the Van's RV-4 climbed effortlessly within the specified rate of climb and speed performance parameters for the aircraft. When climbing to the service ceiling altitude, with the obviously required adjustments to the rate of climb, the aircraft was able to climb to this altitude. Configured for landing, with full flaps and trimmed for a descent rate of approximately 700 ft/min, the aircraft’s approach speed was approximately 75 KIAS and it touched down at approximately 60 KIAS, with a landing roll out comparable with the specifications for the aircraft.

In testing the accuracy of the instruments, based on the measured Test Flight, the speed indications on the airspeed indicator were consistent with the averages measured. Additionally, when establishing a set rate of climb on the vertical speed indicator, the respective gain in altitude on the altimeter was achieved within the measured minute.

In all, Orbx’s Van's RV-4 was very good in flight, displaying the typical flight characteristics of this aircraft. The RV-4 is a lot of aircraft in a small package, sleek and sporty, and this is definitely noticeable in the way it handles. There were some significant flight performance variances compared to the published performance specifications however, but these do not significantly detract from general flying.

Maintenance Interface

The Orbx Van's RV-4 also includes an engine, electrical, and system maintenance interface which can be accessed within the flight simulator. This enables every system to be fully programed with random failures and also records cumulative usage wear and tear.

Technical Requirements

This version of the Orbx Van's RV-4 is for FSX / P3D only. Other specified technical requirements are as follows:
    ●  Windows Vista, Windows 7, or Windows 8 (32 or 64bit);
    ●  Microsoft Flight Simulator FSX with SP1 and SP2 (or Acceleration Pack) or Lockheed Martin Prepar3d Flight Simulator installed; and
    ●  multi core CPU, 1.8GHz or similar, 3GB RAM, 512MB graphics card, and 1.14GB available HDD space.

Simulator Performance

The aircraft model performed excellently within the existing settings I have in FSX. I have most of my settings set very high and there was no need to make any adjustments. FSX continued to perform smoothly and as it would with any default aircraft.

Review Computer Specifications

The specifications of the computer on which the review was conducted are as follows:
    ●  Intel i7 990X Extreme 3.46GHz;
    ●  NVidia GTX580, 1536MB graphics;
    ●  12GB Kingston DDR3 2000MHz;
    ●  Windows 7, (64bit);
    ●  Microsoft Flight Simulator FSX Acceleration; and
    ●  additional major add-ons include: Active Sky Next, REX Essential Plus Overdrive; Ultimate Traffic 2; Orbx FTX Global BASE;
        Orbx FTX Global VECTOR; Orbx FTX region series; and Orbx FTX airport series.


The Van's RV-4 is a fantastic homebuilt, sport aerobatics aircraft and is fun to fly. Jared Charalambous has done a wonderful job of recreating the RV-4 and the aircraft displays a reasonable balance of quality and detail for the price. Whilst some detected issues were significant, they do not impact or significantly detract from the general flying of the aircraft. If you are a fan of homebuilt, sport aerobatics, and / or the Van's aircraft range in particular, this is an aircraft worth consideration.


The Van's RV-4 is a solid aircraft product from Orbx which displays a high visual quality, typical flight characteristics for the aircraft, and represents reasonable overall value for money.

High visual quality.
Realistic general flight modelling.
Comprehensive documentation.

Notable variances and inconsistencies in performance.
Reasonable value for money.

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  Verdict:    silver
External Model: 9.5/10
Internal Model: 9.0/10
Sounds: 9.0/10
Flight Characteristics (does it fly by the numbers) : 8.0/10
Flight Dynamics (does it feel like what it looks like) : 10/10
● Documentation: 9.0/10
● Value for Money: 8.0/10

The Orbx Van's RV-4 is awarded an overall Mutley’s Hangar score of 8.9/10, with an 'Highly Recommended'
and a Mutley's Hangar Silver Award.