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VQ Model P-51D Mustang 46 ARF Review

Take a family-owned model manufacturer from Vietnam, add the clout of one of the largest hobby distributors in the world, and get ready for some 40-sized fun. Ralph Squillace reports.

Splash

Introduction


Wingspan:57.5"/146cm
AUW:5.7 lbs/2.6kg
Length:50"/127cm
Engine requirements:.40 - .46 two-stroke/.60 - .70 four-stroke
Engine:Evolution 46 two-stroke (EVOE0460)
Propeller:Master Airscrew 11x7 (MA1170)
Fuel:Byron Products 15% nitro/16% oil
Transmitter:Futaba 6EX "FASST" spread spectrum (FUTK6900, transmitter and receiver only)
Receiver:Futaba R606FS (FUTL7635)
Servos:Cirrus CS601/BB STD
Factory options:VQ Model retractable landing gear (160223); VQ Model spring-loaded struts (160241); Airtronics CONTEST retract servo (94734Z)
Other options:Robart 2 1/2" wheels (112); Bisson Pitts-style muffler (04046); DU-BRO 12" 2-56 aileron pushrods and clevises trimmed for length; Great Planes Screw-Lock pushrod clamps; Sullivan Gold-N-Cable throttle cable and clevis trimmed for length (507); DU-BRO Kwik-Connect clamps; other assorted hardware
Receiver battery:Hydra-Max 2000mAh 6.0v Ni-Mh (HCAM6351)
Manufacturer:Vinh Quang Model
Catalog numbers:VQA07 (Gunin' For Glory listed as "P-51D Mustang"); VQA08 (Obsession); VQA081 (Bob Hoover Reno pylon racer); VQA083 (Luftwaffe)
Available from:Hobby People
List/street prices:US$269.00/$169.99

For years, my dad's had this heavy-duty automatic wire stripper in his tool collection, and I recently learned of its origin. During the war, my grandfather worked for the North American Aviation assembly plant in Inglewood, California. This was one of two plants which produced the fabled P-51 Mustang fighter plane. This very tool was used to help assemble the full-scale P-51, so it is with pride that I dedicate this review of this wonderful model to my grandfather Salvatore's memory.

Since I happened to finish the model on the day that I myself became a grandfather for the first time, I'd like to dedicate this review to my new grandson Stephen as well!

Kit Contents

Most ARFs generally come in one trim scheme, take it or leave it. VQ offers four P-51D trim schemes. It was Obsession which caught my eye. Its striking sky blue, silver, white and yellow color scheme patterned after that of the 361st FG is remarkably similar to a P-51D at the nearby Palm Springs Air Museum. A photo of the real Obsession graces the end cap of the model's box. As an extra added surprise, I discovered a bonus at the bottom of the box in which the model was shipped. Wrapped in a blue plastic bag were both the retracts and the struts!

The beautifully handcrafted, laser-cut and jig-assembled subassemblies are visually stunning. Never before have I seen precovered models with printed rivet, screw, access panel and panel line detail along with printed graphics. As a result, the graphics are perfectly placed and the decal count is low. Should the unmentionable happen, colored sky blue contact paper is provided for touch ups. To give you an idea of the level of printed detail, you'll find a reproduced Army stencil near the nose of the fuselage which gives the total crew weight and fuel requirements. Look closely at the printed screw heads; they're all at slightly different angles! It's details such as these which set a product apart from the ordinary. A quick examination of all the subassemblies revealed that none required any immediate touchup ironing of the covering, although you'll definitely need to acclimate them to ambient outdoor temperature. I discovered this when bringing the assembled wing to my car on a warm, dry day. The covering started to relax almost immediately. Exposing the tail and vertical stabilizer produced the same results. The wrinkles disappeared soon after bringing the parts indoors; repeated trips outdoors produced progressively less relaxing but it took a lot of trips to make it happen.

The covering itself warrants mention. Unlike the polyester Monokote, Coverite or Oracover you're probably used to, VQ Model uses a thick, adhesive-backed vinyl covering to achieve the printed detail. It reminded me a bit of kitchen cabinet contact paper, but of a much higher grade. It's more like the custom printed vinyl wraps used to decorate full-scale cars and trucks for advertising purposes.

All versions of the VQ Model P-51D Mustang 46 include:

  • Precovered and fully sheeted fuselage
  • Precovered wing halves with fully sheeted undersides and preinstalled lever-operated ailerons with three-piece nylon hinges
  • Precovered tail and rudder with preinstalled three-piece nylon hinges
  • Precovered horizontal stabilizer and elevator with rivet and panel line detail
  • Vacuformed scale details
  • Full hardware package
  • Fuel tank
  • Spinner
  • Prepainted pilot bust
  • Decal sheet
  • Covering patch material
  • Fiberglass engine cowl

You will need:

  • .40 - .46 two-stroke or .60 - .70 four-stroke aircraft engine
  • Pitts-style muffler if you choose to mount the engine in a reclined position
  • Four-channel aircraft radio with four full-sized servos; five-channel radio and retract servo required for optional retracts
  • 2.25" rubber wheels if optional retracts are used
  • Propeller and fuel based on your engine's requirements
  • Receiver battery rated for at least 1500mAh
  • Silicone fuel tubing
  • CA and epoxy
  • Basic tools
  • Basic field equipment

Assembly

Before we begin our full-house build, I'd like to make a couple of suggestions:

  • Click on the Vinh Quang link in the taxobox and print out the online assembly manual. There are a lot of errors and omissions in the printed manual I had, many of which are addressed online and which I'll point out as we go through the build.
  • Read ahead and make a one-time shopping list for new hardware, primarily bolts, screws and wheel collars. VQ uses the best available hardware which can be found in Vietnam, but some of it is either too soft, too short or a combination of both.

One final thing: I did run into some assembly issues, all of which are outlined below. Therefore, the actual steps I took to assemble the plane might be a bit out of order from what you're going to read in the manual.

Let's get busy!

Wing

First, epoxy the nearly finished wing halves together with the plywood dihedral joiner. This is the first ARF I've seen that not only comes with preinstalled lever-operated ailerons which need no further work on the part of the builder to attach and which are fully hidden once joined with the fuselage. The three-piece nylon hinges are generously sized. No "credit card" CA hinges anywhere on this model and no exposed aileron servos and linkages either! The vacuformed plastic wing tips and wheel wells are preinstalled as well. A bit of gentle tugging confirmed that the plastic parts are attached well. The manual calls for 30-minute epoxy; Pacer Z-Poxy is great stuff and strong as steel once it sets up.

The most visible seam, that along the bottom of the wing, didn't quite come together. It seems to be normal; the instructions state that the builder is to "bury the opening" with epoxy and drawings show the seam and the gap in cross section. This is normal; later instructions detail the installation of a plastic cover and simulated air scoop which will hide some but not all of the seam. The rest can be made practically invisible with a thin strip cut from the repair film.

After the epoxy set, it was time to trim away the covering for the hardwood frame which I attached with thick CA and which holds the single top-mounted aileron servo. Those concerned with VQ's use of a single servo need not be; the mechanical advantage provided by each aileron's lever more than suffices. There's also the added advantage of scale detail; as previously mentioned, no servos, pushrods or control horns dangle under the wing. I'm also using one of the most powerful standard servos on the market and the strongest standard servo in the Cirrus line. The ball bearing-equipped CS601/BB STD pumps out a gargantuan 102 oz/in (6.5kg/cm) of torque at six volts with a transit time of only .16 seconds for 60 degrees of throw. That, dear friends, is pure muscle. The mechanism is completely hidden once the wing is installed. For that matter, there's a weight advantage as well. While the supplied pushrod clamps worked fine on the bench, I'm not comfortable using clamps which are attached to the servo horn via a threaded rod and knurled nut. The tiny set screws were a bit too tiny for my taste as well and so I elected to substitute Great Planes Screw-Lock pushrod connectors throughout.

Speaking of servos: Global Hobby generously provided a full complement of utterly beautiful, fast and powerful Cirrus CS601/BB STD ball-bearing servos and an equally beautiful low-profile retract servo, a Cirrus CS503R/BB. After all, a first-class model deserves first-class servos, and these fill the bill nicely. Unfortunately, the retract servo met with an untimely demise, but it was graciously replaced by Global.

It was here that I'd found yet another thoughtful detail on the part of VQ. At first, I thought that all of the hardware came jumbled together in a single plastic bag. I'm pleased to report that I was wrong. The bag actually holds a number of hardware packages each in their own Ziploc-style bag.

The aileron servo required that a channel be cut in the mounting frame so that the lead can thread through the mounting lugs from underneath, a step not mentioned in the instructions. The retract servo had a more serious problem. The wing struts were mounted a little too far apart. Trying to center the servo between the struts resulted in a cracked strut when trying to drive the screws. I glued a thin piece of balsa to the cracked strut facing the servo case to take up the slack. It worked, but the new balsa is cracked. Worse, the opposite strut cracked as well. The wood throughout the wing, while of good quality, is rather soft. While the installation turned out to be rather sturdy despite the cracks, I took no chances and reinforced the damage with some CA. A servo tray might be an excellent idea here, depending on your choice of servos. So too would be to drill some pilot holes and to consider using better quality hardware.

Optional retracts

Once the servos and aileron pushrods are installed, it's on to the landing gear. You can go with the fixed gear enclosed with the kit, install the optional retracts as is or go all the way with VQ's beautifully engineered and highly realistic spring-loaded struts. However, no instructions are provided as to exactly how the spring-loaded struts are to be installed on the retracts. Rather than risk ruining the retracts and struts, I requested the factory procedure. VQ acknowledged the omission and promised that future production of both the struts and the plane will have an addendum as will the website. Instructions were pretty much what I'd assumed, that is, to cut the shaft off at the loop, grind a flat spot on the remaining stub for the setscrew, adjust the strut on the stub to fit the preinstalled wheel wells on the wing and to retain the setscrew with a bit of blue Loctite. The little 3mm set screws weren't up for the task, and I substituted 3x6 mm allen head screws from DU-BRO. These struts are on to stay! If you wish to remove the factory struts from the retracts before cutting, simply loosen the allen head set screws on either side of the mechanism, and then twist the strut back and forth to help pull it out.

You're required to bend and shape your own retract pushrods with the unbent ones supplied. Except for these drawings plus an additional drawing showing the orientation of the pushrods at the servo, no other instructions are provided, and the drawing is a bit unclear as to exactly what has to be done. The given distances of 100 mm between the bends and loops you need to make for the left pushrod and 150 mm for the right still makes for too-long pushrods; the final measurements were more like 80 mm and 130 mm respectively. The decorative pre-installed wheel wells do not allow for full travel of the struts with the spring-loaded units in place, and the wells make it impossible to install the pushrods in the first place. Trying to remove one of the inserts threatened to result in torn and damaged covering and did result in a damaged insert.

I took an X-Acto and gently cut through the covering surrounding the PVC inserts. They came out, but they'd been taped to the covering which in turn was stuck to the frame.

In order to repair the damage to the covering, I trimmed off the perimeters of each wheel well and reattached them to the wing with some contact cement and a dab or two of CA where needed. The result, while allowing the retracts to work, was not completely aesthetically pleasing!

The good news here is that the pushrods are much more accessible less the wells, but you'll have to do a lot of trial and error to get the pushrods to work properly. The way that seemed to work best for me was to hook the servo to the radio and to flip the switch to the extended position. I installed the ends at the servo per the drawing and then adjusted both the pushrod's metal clevis and the retract's nylon horn to fit. Trial of the system resulted in binding of the linkage due to interference, so I reduced the radius and trimmed the rods for length at the servo end until everything worked smoothly.

All of the trial and error resulted in one broken clevis, and the nylon horn on one of the retracts cracked as I was trying to remove the remnant of the clevis. The hobby shop doesn't stock 2 mm threaded metal clevises, but they do stock 2-56 DU-BRO pushrods with pre-installed metal clevises. DU-BRO also makes an inexpensive adjustable pushrod kit which came with two horns of roughly the proper size. I replaced the 2 mm aileron pushrods with the 2-56's and screwed one of the 2 mm clevises to the retract pushrod. The DU-BRO horns are a bit large for the aileron levers, but not by much. Squeezing them together with pliers before installation made them fit as well as the originals. I elected to use a dab of CA for insurance, but it's possible to clamp the horn on either side with 3mm nuts.

Finally, success! The retracts worked great, locking in place without fail in either position, at least without the wells. I wasn't out of the woods quite yet, though. The hubs fit fine on the regular retracts, but not on the larger axle of the spring-loaded units. These foam tires aren't intended for use with the retracts, but there are no instructions telling you so (at least not yet). According to Global, the factory did their R&D with Robart #112 2 1/2" wheels, and I followed suit. New wells from Global arrived as well.

Finishing the wing requires the attachment of the mounting plate, simulated air scoop, nylon attaching bolts and the front cover, all of which was straightforward. With regards to the mounting plate, there were more omissions in the manual. The plate, with the thoughtful addition of a laser-etched centering line, should be installed with the tapered end facing the front of the wing in order to mate properly with the air scoop's mounting plate, but this isn't indicated as such. The manual also instructs you to drill the mounting holes from the top, but don't. Simply drill the holes from underneath through the existing holes hidden by the covering on the wing once the plate has been attached with CA. I soaked mine with water in order to bend it to fit the dihedral.

Moving on to the scoops: It would have been nice to have fiberglass parts to match the beautifully finished fiberglass cowl, but they are fine. The mounting bolt access holes, once opened, don't quite line up over the center of the bolt heads, but you won't have any trouble accessing them. Strangely, there's no simulated black opening at the air scoop, but that's easily fixed either with a bit of paint or, as I did, with some black self-adhesive trim paper.

The new wells turned out to be for the Swiss Army version of the P-51B and were painted solid silver as opposed to the white and blue originals. Since the full-scale Obsession is a made-up color scheme anyway, I elected to leave the wells in silver as they looked great against the blue/white color scheme with invasion stripes. Once installed, back came the interference problems between the struts' scissors hinges and the wheel wells. I noted some interference where the top of the spring loaded strut was supposed to tuck into the well, but I made the decision not to start carving on those covers. The interference didn't look to be enough to worry about

My solution was to push out the outer edge of the wells and attach them to the wing with Great Planes #2 x 3/8" button head sheet metal screws. That way, I could start the pilot hole with a pin vise, use an .050" allen driver to drive the screws home and not risk slipping a screwdriver through the covering.

As I'd learned soon after removing the original wells, there is some extremely soft wood on that part of the wing which didn't take kindly to being stressed with a stretched plastic cover. The retracts still would not raise all the way due to interference where the scissors hinge meets the well, though with less interference than before. I also learned that a 4.8v receiver pack strains to raise those retracts with those Robart wheels dangling underneath. At least they extend and lock properly. No recommendation is made regarding a receiver battery; the distributor recommended a 6.0v 1500mAh pack if you're using retracts. I wound up using a 2000mAh 6.0v AA Ni-Mh pack from Hydra-Max.

Wow, did that pack ever make a difference. The gear raised immediately, but they still interfered with the wells and still would not lock in place. I'd attempted to better attach the servo horn so that the retracts would come all the way up, but now the servo wasn't turning fully, unbeknownst to me. I turned away for a moment and when I turned back around, smoke was pouring from the retract servo! Global was kind enough to offer to send a fabulous replacement.

The new servo was a top of the line Airtronics "CONTEST" ball bearing servo with equally good transit time, but a much more forgiving nature. Both the Airtronics and the Cirrus rotate slightly more than 180 degrees, but the Airtronics has a bit more free rotation, making it much more forgiving during its setup. The retracts still don't quite raise all the way into the wells, but they do raise sufficiently. You'll need to drill a couple of 1/16" holes in the lower part of the undrilled, double-decker arm. I followed Mike's advice and drilled one notch in from the extreme outer hole. No more binding! I did notice that it took about 90 degrees of rotation before the gear would raise, so hose spring loaded struts are going to need a lot of room to come up properly.

If by now you're doubting whether or not you want to pop for the retracts after all this, please don't write them off as of yet. I'd been in close contact with Global throughout the installation who in turn relayed my concerns to the factory. They in turn should implement whatever changes are necessary as soon as possible. Installing the retracts less the spring-loaded struts should prove to be no problem at all with a little bit of patient setup.

Fuselage

Engine installation

Once the wing is done, it's time to move on to the engine installation. It's clear that VQ put a lot of thought into the subject given the wide range of engines the P-51 will accept.

The manual says that the thrust angle is set at the factory, but the firewall is straight up and down. Instead, VQ set the thrust angle with two glass-filled nylon mounting spars. Laser-scribed alignment lines on the firewall correspond with alignment marks on the mounts. The ones on the firewall are a little hard to see under the black paint, but they are there.

There was a slight but welcome variation between the manual and the actual Ziploc-bagged hardware package. The manual suggests that the mounts bolt to the firewall with 4x25 mm bolts backed with standard 4mm nuts and washers. I was all ready to buy blind nuts... until I opened the bag and there they were. Installation of the blind nuts was greatly simplified by a mechanic's magnetic tool pickup wand. In addition, you have 3mm bolts about 18 mm long plus the necessary nuts and washers needed to bolt the engine to the mounts; the manual suggested self-tapping screws.

A pushrod and sleeve are provided for throttle control, and its installation is at least touched upon in this section, but the example shown in the drawing is a four-stroke. My two-stroke Evolution 46 has a different throttle arm location than what's shown. It's a fairly straight shot from the carb to the servo in my instance, but I didn't want to risk binding a pushrod, even with the enclosed tube. In its place went a Sullivan #507 Gold-N-Cable like the one that went on my previous project. I drilled a hole in the bulkhead immediately in front of the servo to eliminate any possible flex in the tube, securing it with CA. I remounted the servo arm about 45 degrees aft since that Cirrus servo has a lot of throw, even with the EPA turned down. That kept the cable from flexing at full throttle and I still have plenty of throw. I elected not to fully secure the engine mounting hardware with Loctite until the cable and servo were installed. Although the enclosed 4x25 mm bolts are adequate for bolting the mounts to the firewall, I wasn't comfortable with the combination phillips and slotted heads, especially since the heads were proving to be soft. In their place went four DU-BRO 4x25 allen head bolts pulling on the factory blind nuts.

You're instructed to mount the engine with the cylinder reclined to the right. No muffler is shown in the illustration, and the standard muffler on the Evolution is pretty indicative of what you'd find on any engine. In fact, all the manual instructs you to do is to mount the engine in such a way so as not to have it come in contact with the fuselage. I'd become concerned at this point as to just how much surgery the cowl would need in order to clear this muffler and wound up dropping $28.99 on a Bisson. The only other things I needed to make it work with the Evolution 46 were a new muffler gasket since the one on the engine was brittle plus a couple of 3x35 mm bolts for an O.S. .40 or .46 since the Evo's 3x40 mm bolts were far too long.

Here's where you'll need to refer to the online manual.

To use a standard muffler with a two-stroke engine (and likely a four stroke as well), that version instructs you to mount the engine so that the cylinder points at a 45-degree angle to the right, thereby putting the muffler down the right side of the plane and avoiding excess surgery to the cowl. Should you attempt to install the engine with the cylinder reclined at 90 degrees, a stock muffler won't properly clear the fuselage. This is corrected in an online addendum and not in the instructions. Since I had began trimming the cowl before fitting the muffler, I was afraid I'd wind up with a ruined cowl with a giant, off-center hole for the cylinder. As it turned out, the extra room was necessary to clear the Pitts muffler which took up most of that hole. The hole also makes it possible to install the muffler after the cowl is installed. I already had to drill one hole atop the cowl to access the high-speed mixture screw and therefore the aft muffler mounting bolt; it was only a matter of drilling a second hole to access the forward bolt. A third hole was drilled on top for a Central Hobbies Fuel Dot fuel filler cap.

You're then instructed to assemble and install the fuel tank. If you're running a two-stroke, you're told to install the battery under the tank in a later step, requiring one to remove the tank later on. Four-stroke users are instructed to place the battery in the empennage and the manual is fairly detailed as to exactly where it's supposed to go, but you'll run into a bulkhead at the recommended 120 mm location behind the trailing edge. As I'd discover later, this is where the battery should be placed in the first place, especially with the weight of the retracts. Since I'd planned to try and save weight, I got a flat pack which in this case is the aforementioned Hydra-Max 2000mAh nickel metal hydride unit. Lots of room in either location, by the way. A hump pack will fit just fine in the tail if need be and would likely be a better choice to help balance the model.

Now that everything was properly trimmed and centered, once again with help from the scribed marks on the firewall, I assembled the fuel tank. Then, in went the battery wrapped in some quarter-inch foam followed by the fuel tank, all of which had to come apart later to relocate the battery. Once the lines were hooked up, on went the cowl followed by the muffler, gasket, prop and spinner. The hole in the center of the spinner's back plate hadn't been drilled out, but it was no problem opening it up with my drill. A quick test run of the engine the next day less the cowl was a success, requiring only minor adjustment of the throttle cable since the idle was too high. Standard stuff, but those errors in the manual made it a lot more dramatic than it needed to be.

On went the cowl the next day, this time for good, or at least until I remove it in order to better radius the openings I made. It's attached with four 2x10 mm screws which have plenty of bite while a cut-down 1.5 mm allen wrench from an E-flite Blade CP parts package was chosen to serve as a remote high-speed adjustment knob. Blind nuts for the cowl mounting may be a possibility down the line, but not until I remove the cowl, prop, muffler and fuel tank for future maintenance.

Tail

Installation of the vertical stab is as simple as trimming off some overlapping covering from its slot in the fuselage and removing a bit of covering from the bottom edge of the stab itself. I was a bit worried when I saw that the elevators and their marvelous pinned hinges had been preinstalled on the horizontal stab, but the left half pulled out with gentle pressure. Actually, the stab will fit in either direction once you trim the covering from its opening in the tail. The graphics are identical on both sides.

Once I was satisfied everything fit correctly and that no shims were necessary, I removed the parts, trimmed the covering, attached the wing so that I could triangulate the horizontal stab, mixed up some 30-minute epoxy per the manual and reinstalled everything. The measurement from the rearmost corner of the aileron to the rearmost corner of the horizontal stab turned out to be 20 3/4 inches; lateral is about 6 1/2 inches, but the wide elevators won't allow much lateral motion anyway, making it really easy to line up properly. Just remember to glue the hinges to the stabilizer; they're already glued to the elevator halves. They're a nice, snug fit, but CA or Zap-A-Dap is cheap insurance.

On we go to the tailwheel installation and its hidden linkage. You'll need to remove the preinstalled cover plate to get to the preinstalled tailwheel bracket. While the pushrod arm is a tough, well-made nylon affair with a brass bushing and a generously sized setscrew, the same can't be said for the collar that's supposed to hold the rubber tailwheel in place. Don't even bother trying to use it; you'll only strip the threads. Besides, you'll need two 1/8" collars anyway in order to center the wheel on the axle.

You should run the pushrod through before you go through the hassle of aligning the arm and shaft and snugging it down; it'll only have to come off again. I am so glad I read ahead since there’s nothing in the manual to alert you to this.

The rod is inserted from the tail forward. Attach the arm to the pushrod's z-bend and feed it through. It's very long, and you'll have to trim it later. Once it's threaded, attach it in the same manner you would a steerable nosewheel. I used a drop of Loctite to hold the setscrew, which in turn engaged the flat on the bracket perfectly. It proved to be difficult to tighten, so do what I did after the maiden flight and use a 3x6 mm socket head bolt like I did for the retract struts.

The simulated retract covers are silver-painted balsa. They're a nice touch that a little bit of aluminum or silver trim tape will easily enhance. A friend who does spray-on truck bedliners gave me some aluminum tape which is generally used for HVAC installation but which he uses to patch holes in a truck's bed before spraying on the liner. Called "Venture Tape," it has an attractive, brushed finish. You'll have to figure out a way to remove the printing; I merely cut around it. If you open up the wheelwell, be forewarned that there isn't anything underneath except for a lot of empty fuselage. It's a small opening and adds a nice scale touch in the meantime.

Radio Installation

There is a tremendous amount of room in the P-51's fully sheeted fuselage. It's a beautiful example of light yet strong construction which has the added advantage of heightened realism on the outside since there aren't any visible stringers. There's also plenty of room inside since the sheeted construction does away with many of the bulkheads and stringers. Nice work, VQ!

The next step in the manual is the installation of the elevator and aileron pushrods. The servos are shown installed in that step, but the next step is supposed to be the servo installation. I chose to install the servos first in order so that I wouldn't have to work around the pushrods later. Note too that the drawings between sections conflict with regards to the throttle servo; the illustration in the pushrod section is correct as are the drawings in the online manual.

I started with the rudder by first attaching one of the extremely strong, glass-filled nylon servo horns and then sliding the pushrod in from the rear where it exited next to the tailwheel pushrod. It's longer than the fuselage, so don't worry about length.

Those horns were seriously impressive, but here's where I was really impressed. Problem: Operating four items with only two servos, namely the elevator, wheel and each elevator half. Solution: An ingenious triple clamp. Your servo arm activates a central pushrod which in turn will push two other pushrods, two for the rudder and two for the elevator. This keeps the scale look of the tailwheel and does away with a wear-prone elevator joining wire. Marvelous!

Once the pushrod is in, test fit the servo horn to the rudder. The holes in the horn should be 10 mm from the hinged area. Mark where the holes are supposed to go with a Sharpie or a pin vise and drill a couple of 5/64" holes through the rudder as well as the horn while you're at it. It's then as simple as inserting the screws and attaching the horn with a back plate. Standard stuff. Do the same with each elevator half.

A couple of minor problems popped up here, both yet again related to hardware. The 2x10 machine screws intended to attach the horns to the backplates were far too short. Another trip to the hobby shop for hardware, this time some 2x12 bolts and 2mm nuts. The bolts fit through to engage the back plate, but barely enough to engage it properly and certainly still too short for the nuts. I wound up using 2-56x3/4" machine screws and nuts held with a dab of Loctite to attach the horns. They stick up a bit, but not too much. The nuts give it a bit more insurance; these horns aren't going anywhere.

Problem number two was with one of the triple clamps. Each clamp has four sets of three holes each. Three holes are for the pushods and six are tapped for set screws, a nice redundancy. Two holes on one side of the clamp which were supposed to be tapped were only partially so. No way to get a setscrew through either one. I e-mailed Global, who offered to send me the clamp. In the meantime, I would begin the search for a 3 mm tap, which I found a lot easier than I thought I would the next day. It worked great, and I took the time to chase the remaining threads to keep the set screws from binding. The illustrations in the printed manual are okay, but the online manual's are far better when it comes to installing this system.

Finally, in went the power switch, but not in the recommended location. That recommended location is inside the fuselage on the servo tray, wrapped in a piece of 1/4" Hobbico foam rubber and secured with a tie wrap.

I kept wondering why the switch would be mounted inside the plane, accessible only with the wing removed, but it was a simple matter to mount it externally on the right side of the fuselage just above the throttle cable, nicely squared up courtesy of some printed panel markings. The area which was intended for the switch serves instead as the receiver mounting area. I wrapped a Futaba FASST receiver in more of the 1/4" foam and attached it to the switchplate with a tie wrap.

Completion

I'd jumped ahead a step when I'd installed the cowl; it's the manual's next to last assembly step behind the few decals necessary to finish. In my case, the canopy, pilot and decals are the final phases.

The pilot bust and his simulated headrest went on first. The headrest is carved from balsa and attaches to the cockpit and the rear of the bust's helmet with a dab of CA. Since the cockpit is a preinstalled, vacuformed part painted the same bright blue as the rest of the plane, you may wish to add some paint detail so that your pilot isn't awash in a sea of blue. Warranting special mention, the hollow resin pilot bust is totally handpainted and, quite frankly, looks terrific if a bit too large and shiny. A P-51 is a big plane, but you wouldn't be able to tell by looking at the pilot of this model! I've seen more than my share of poorly painted pilot figures in the past, but I assure you, this isn't one of them.

After the bust took his rightful place in the cockpit, on went the peel-and-stick instrument panel decal which, though precut, still needed trimming to fit on the dashboard and slicing to fit on its contours.

It'll be necessary to break out some scissors to trim the excess material from the canopy. Diecut vinyl decals provide the canopy frame detail.

The finished canopy attaches to the cockpit with four 2x6mm screws, but measure those holes carefully. There isn't a lot of area on that cockpit for the screws to engage. I played it safe and used six screws.

The rest of the decal installation was pretty much a nonevent with the most work needed on the contact paper invasion stripe decals atop the ailerons. Though cut at the proper contour, some trimming for length and width was still necessary. Sadly, the large opening on the right side of the cowl precluded me from adding the Obsession script and cooling vent decals. Those of you who might wish to consider converting the P-51 to electric power obviously won't be faced with those issues, not to mention you'll have a far more scale-accurate rendition up front.

Flying

Basics

I hadn't the time to double check the CG or the radio settings the night before I took the P-51 to the field, so I decided to do the final tweaks to the model while at the field.

Fortunately, the field was busy and lots of club members stopped by to say hi and to check out the plane. That color scheme drew universal admiration.

I had the good fortune of running into Mitch Hall (mlh1961). Mitch is as generous and as classy a guy as you'd ever want to meet, and together we began getting the plane ready for flight.

First thing: Nose heavy. Oh, was it ever. I had a feeling that it would be with the weight of the retracts and the battery, not to mention the weight of the Evolution 46 with its Bisson Pitts muffler. Rather than add excess weight to the tail, I drained the fuel tank and took the front of the plane apart in order to remove the battery from atop the tank. Mitch grabbed some Velcro from his toolbox and proceeded to mount the battery in the tail as far as it would go (a bulkhead allowed it to go only so far back). In this position, it was necessary to use one of the servo extensions I was going to use for the wing in order to run the battery lead back to the switch.

It was still nose heavy after reassembling everything and refilling the tank, though not as much. Mitch came through with about 1.5 ounces/43g of self-adhesive lead weights and some surgical tape. We put some of the tape under the tail, stuck the weights to the tape and topped off the weights with a second layer of tape. Unattractive, to say the least. However, that little bit of weight did the trick. The P-51 balanced right on the 132 mm mark behind the leading edge. I finished programming the radio with the recommended throws of 6 mm for the ailerons, 10 mm for the elevator and 35 mm for the rudder. I added no exponential, but it didn't need any. That is very good news for flyers with a sport radio. Finally, after more than an hour of tweaking everything, the P-51 stood ready.

Club president Dan Metz was on hand as well; he's helped me maiden both my other review subjects to date and offered his assistance on this latest one. He couldn't detect any washout or misalignment anywhere on the P-51, a testament to the overall quality of this model, although the three-piece hinges on the elevator left what he felt was too large a gap between elevator and stabilizer. We double checked the landing gear and found one of the stub shafts was loose in one of the landing gear mechanisms. There was also a bit of play in the tailwheel which I simply couldn't eliminate. Once everything was checked and fixed, Mitch, Dan and a guest of Dan's fired up the Evolution, set the high end and set up the plane for takeoff with Dan at the controls.

Taking Off and Landing

Ground handling was very good, but twitchy. The culprit was that wiggly tailwheel coupled with 40 mm of rudder stroke with no expo. Still, the P-51 displayed no tendency to want to drop a wingtip. In fact, its steering response coupled with the lack of scraped wing tips would have been the envy of an R/C car fan.

I fired up the video camera and Dan fired up the P-51.

The tailwheel made the initial run to takeoff speed a bit touchy and caused it to veer left as you'll see in the video, but once the tailwheel lifted off, the plane tracked as straight as a laser right up to takeoff.

Before this point, I'd been concerned whether that little .46 was up to the task of hauling that plane and its heavy hardware into the air, much less down the runway.

I needn't have been. That model smoothly hurled itself into the afternoon sky without so much as a hint of strain. My initial reaction: WOW!

Aerobatics/Special Flight Performance

Just about the time that Dan was getting ready to retract the gear, a minor mishap occurred. One of the wheelwells had popped loose and half of it was dangling at a 90-degree angle below the wing. It certainly didn't seem to affect the flight characteristics or speed, the latter of which this model has in abundance as noted by everyone present. Dan estimated a top speed of around 80 mph (130 km/h). No slouch is this.

He made some minor trim adjustments and brought the plane in for a nice, gentle landing so that we could fix the wheelwell. Relocating the screws to the top inside corners of the wells solved the problem and it was back into the air once more.

The initial test was a stall test with the gear still lowered. Up, up, up went the nose as the throttle came down. When the stall did occur, it was almost as if gravity itself was being defied. The P-51 just hung there at a 45-degree angle before the nose began a graceful, downward arc. A CG test was next. Dan brought the plane up to where it was for the stall test and did a hands-off, 45-degree power dive.

Flawless. The model showed no signs of deviation from its course.

Once the plane was leveled, we figured it was time to raise the gear. Except for a mere "blip" of upward thrust as the gear raised, there was no effect on the flight characteristics once they were retracted. With a "clean belly," the P-51 seemed even faster and passed the stall and CG tests once more with flying colors even though the wheels still wouldn't completely raise into the wells.

Loops, both large and small, were as easy as doing them on a simulator with almost no tendency to wander at the top of the loop. I say "almost" only because Dan had correctly guessed that one of the elevator halves had shifted ever so slightly out of alignment. Had that not been the case, he had no doubt that the loops would have been even more locked in.

Rolls were equally as graceful. Not too fast, not too slow. So good were the roll characteristics that Dan felt confident enough to do a slow roll with a little more help from the rudder. Again, flawless. I could tell that he was genuinely having fun flying the P-51. Inverted flight was equally as much fun, requiring about fifteen degrees of down elevator to keep it level. From there, he actually was able to pull off a nice, short outside loop to bring the plane back to normal attitude. He offered to hand off the radio to me, but I declined because the sun was in such a bad place. That's also the reason the video I shot was so shaky. I couldn't see the viewfinder, so I couldn't tape the stall and roll tests. So, down came the gear and in she came for a nearly perfect landing with just a single bounce.

What a ride.

I returned at the first available opportunity several days later in order to try and get better video and to try this plane out for myself. I pointed out earlier that I'd used a DU-BRO 3x8mm socket head screw to tighten the loose tailwheel, but it was a bit difficult to get an Allen key in the space to tighten it. I eventually got it down, but a 3x6 mm screw would have saved some headaches.

Ground handling was marvelous without a hint of wander. Wind was from the south, so I taxied the P-51 to the north end of the runway, pointed it into the wind and brought up the throttle.

What few preflight butterflies I may have still had disappeared the moment the P-51 started to roll. Off it hurtled down the runway with the tailwheel lifting off first. It took very little elevator to get it airborne. My first coordinated right turn after liftoff was absolutely effortless with no tendency for the nose to drop. Up went the gear and on came the fun. A few little zigzag turns later to get a feel for the ailerons and I was as comfortable flying that plane as any I've owned for years. It cruised at a nice, comfortable clip at about half throttle, but when I poured on the ponies, I got to experience that 80 mph rush for myself. The color scheme and sheer size of the thing made it exceptionally easy to track in the sky.

I kept the aerobatics to a minimum with just a few rolls and some really easy inverted flight, but it inspired enough confidence even on this first flight that more advanced maneuvers will soon be almost second-nature. I even tried a brief burst of vertical flight and it showed almost no signs of slowing. A four-stroke and the right prop would likely equal unlimited vertical. I dropped the gear during a fly-by, swung the model to the right in a wide arc over the helicopter pad to bring it in for final and the P-51 glided in as easily as a trainer. Since it's a low-wing warbird, I'd kept some power on during the landing, but the tail wanted to stay in the air. When the mains touched, I had no ground control and it drifted to the right off the sideline of the runway into the recently smoothed dirt. No harm, no foul with the possible exception of some sore facial muscles. Turns out I'd been grinning like an idiot during that entire flight and for good reason:

The VQ Model P-51D Mustang 46 is a blast to fly, pure and simple.

Grandpa would have been proud.

Perhaps someday, my own grandson will be as well.

Is This For a Beginner?

I would have to say absolutely not and for a number of reasons. One, a modeler with no real building experience is going to have a heck of a hard time following the directions and assembling the retracts. Even with my modeling experience, I managed to spend days setting up the retracts only to burn out a very expensive servo, not to mention the incorrect mounting of the engine and near-destruction of the expensive cowl. Two, this is a very fast and responsive airplane as equipped with a two-stroke engine. I can only imagine the capabilities of this plane with a four-stroke. Three, it has none of the self-righting and slow-responding characteristics of a trainer.

The overall level of quality and performance coupled with a very reasonable purchase price would make this an excellent choice for any intermediate or advanced modeler. All of the bugs regarding the retracts, hardware and documentation are being addressed by Global Hobby and VQ Model as you read this. If you elect to assemble the P-51 with the fixed gear, new hardware and this review as a guide, you'll have it up and running in very little time.

Flight Video/Photo Gallery

Downloads

Conclusion

As I'd pointed out earlier, if you're willing to forego the fancy retracts and are willing to purchase a bit of upgraded hardware, you'll be rewarded with a 40 sport flyer with scale looks, blistering speed and locked-down, laser-accurate handling. Adding the retracts will add another dimension to the fun, but be prepared for a lot of work!

Global Hobby's decision to distribute VQ Model was a wise one. The assembly, engineering and documentation problems I've outlined are easy fixes and are all that keep this model from the upper echelon of ARFs as delivered. When all is said and done, it's some of the most flying fun you'll have with a warbird and more than worthy of your consideration. Now that it's together and flying, I love it. Get one and I promise you'll love it too.

See you at the field!

The many pluses of the VQ Model P-51D Mustang 46 include:

  • Fine, handcrafted construction
  • Beautifully printed, sturdy covering with matching patch tape included for repairs
  • Printed covering allows for several trim schemes, even weathering on certain versions
  • Fully sheeted fuselage with no stringers visible on the outside
  • Strong, sturdy three-piece hinges and nylon-filled control horns
  • Beautifully handpainted pilot figure
  • Stable, predictable and accurate flight characteristics
  • Largest recommended two-stroke as tested resulted in amazing top speed
  • Hidden aileron linkages add to scale detail
  • Triple clamp setup for elevator, rudder and tailwheel eliminate the need for a wire joiner between the elevator halves and allows for much more accurate fine tuning of alignment
  • Full-sized servos mean plenty of power to move the control surfaces at any speed
  • Support of one of the world's largest hobby distributors

There are a few minuses as previously discussed:

  • Errors and omissions in the manual ed to an improperly installed engine and a nearly destroyed cowl, although many of the issues in the manual have been addressed online
  • The retracts were difficult to install, made more difficult by the pre-attached wheelwells, poorly documented pushrod specs and poor fit of the spring struts in the wheelwells, not to mention a complete lack of documentation
  • Retracts simply will not raise all the way
  • Some poor quality, ill-fitting hardware
  • Covering takes quite a few exposures to outside temperatures before it becomes acclimated; it wrinkles immediately upon exposure to sunlight
  • Pilot figure is out of scale
  • Dashboard decal doesn't fit without trimming
  • Precut vinyl canopy trim prone to slight wrinkling of the edges
  • Optional retracts make the plane extremely nose heavy, making it necessary to add weight to the tail
  • Wood used to support the retract servo is very brittle and is spaced too far apart
  • PVC parts look a bit cheap as do the painted wood simulated tailwheel covers
Last edited by Angela H; Feb 23, 2008 at 08:06 AM..

Discussion

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Old Feb 27, 2008, 08:00 AM
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Thank you for the review. Was down/right thrust built into the firewall on this model or was it build into the engine mount?

Any thoughts on how this model would do as an electric conversion?
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Old Feb 27, 2008, 10:28 AM
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Full Tank?

Did I read that right? You balanced it with a full tank?

Jim
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Old Feb 27, 2008, 10:36 AM
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You're welcome! I hope you found it useful.

The firewall looks as if it's straight up and down, but I can measure it and get back to you. The mounts appeared to take care of the thrust, although there isn't a whole heck of a lot. The manual claims that some thrust is built in at the factory, but whether in the mounts or in the firewall, I'm not sure. Again, not a lot of angle, but it flies fine.

I think it would make a great electric conversion. In fact, it would likely balance better with a big outrunner and a li-po up front as opposed to an engine.

I had about half a tank in it when I checked the balance, but it was so ridiculously nose heavy that it wouldn't have balanced even without the tank in place because of the battery. We pumped about that same amount back in after we relocated the battery. That's when we added the tail weights as well since we could only mount the battery just so far back. Sorry if that came out wrong in the article.
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Old Feb 27, 2008, 11:14 AM
"Have Glue - Will Travel"
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Nice review Ralph! The 'robot cow' comment had me rolling

Ronnie
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Old Feb 27, 2008, 01:04 PM
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Quote:
Originally Posted by dawnron1
Nice review Ralph! The 'robot cow' comment had me rolling

Ronnie
Really? I breed robot cows and was kinda hurt by that remark.
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Old Feb 27, 2008, 01:49 PM
"Have Glue - Will Travel"
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Quote:
Originally Posted by Socomon
Really? I breed robot cows and was kinda hurt by that remark.
LOL

Remember the Far Side cartoon with the 'Cow Phone'?
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Old Feb 27, 2008, 01:50 PM
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I was a Far Side fan back when, but I don't remember that one.

Edit: God bless google - there isn't anything you can't find:

http://www.b-eye-network.com/blogs/myers/cow.jpg
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Old Feb 27, 2008, 02:43 PM
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Yeah, The Far Side was indeed greatness. I hope Gary Larson is livin' it up in retirement!

Great blog and avatar, BTW Steve! "Yes, I am Nacho..."

Ronnie
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Old Feb 27, 2008, 02:57 PM
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Muchas gracias Senor Ronny.

Back to the topic at hand - I kinda have my eye on the swiss B version of this plane, but I think I should wait for a later production run so they can get the bugs out.
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Old Feb 27, 2008, 05:34 PM
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Oh, is this ever hilarious! You know, I actually had visions of beleagured cows and little fat guys with thick glasses as I wrote that comment. It really DID remind me of The Far Side! In fact, look at the full-sized picture; the tabs of the Ernst stand look like ears! SUPERCOW, AWAY!

I actually took it out to the field today, but I couldn't get it flying for a number of reasons. One, I forgot the glow plug clip that plugs into my power panel and the battery-operated on I had was weak, making it hard to start. I was having a bit of trouble setting the high end, which resulted in stalling and the eventual total loss of the ignitor's power. Two, the right gear kept collapsing whenever I tried to taxi out onto the runway. Pushrod needed tweaking, but it took a bit of doing. Wing on, wing off, wing on, wing off. By the time I got it working, the ignitor was kaput. All that time spent at the club and all I got to do is drive it around the runway like a car!

BTW: Socomon, if you really are breeding robot cows, you might talk to Global Hobby about having them sign a non-competition clause if they want to keep selling these models!
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Old Feb 27, 2008, 05:41 PM
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PMDrive - that is just plain silly. You know our intellectual property laws are given little deference is Asia, furthermore robot cow husbandry is no laughing matter!
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Old Feb 27, 2008, 05:43 PM
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Nuts. You're right. Property laws just go out the window in situations such as these. As far as the husbandry thing is concerned...you are SO on your own, old buddy.
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Old Feb 28, 2008, 07:59 AM
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Quote:
Originally Posted by Socomon

Back to the topic at hand - I kinda have my eye on the swiss B version of this plane, but I think I should wait for a later production run so they can get the bugs out.
I don't know if you have seen an actual photo of the model or not, but here it is.

Honestly the 1 aileron for the ailerons is very old school to me. But hey, if it works....

Tommy D

P.S. I like the hand drawn photos of the Swiss 51 better then the photo I'm afraid...
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Old Feb 28, 2008, 08:23 AM
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Hmmm . . . that aileron is HUGE. It is the whole span of the wing. Although is it kinda like the HK Spit in that regard.

I'd have to see what it looks like assembled before I could judge it, but on its face I would agree that it probably won't look as good as the drawing - which looked pretty slick.

PS - where did you find that pic?
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