ParkZone’s New BNF

P-51 Mustang BL

By: Martin Fredericks

The original ParkZone Mustang was one of the ground breaking models that introduced foam construction and stable, yet aerobatic performance, in a true Ready-To-Fly (RTF) fighter. Pulled aloft by a strong 480 brushed motor powered by Ni-MH batteries, the ParkZone Mustang was fun and easy to fly. The RTF radio was a neat little 3-channel that operated on the 27 MHz band. While interference was never experienced, 27 MHz is one crowded frequency band and three-channel operation has its limitations.

However, flight times were less than 7 minutes and vertical performance, while adequate, could be improved. But most of all, there was no rudder. While the Mustang was aerobatic, being rudderless meant the airplane was also snap roll-less, stall turn-less, trackless while inverted and could not be slipped to a landing. While flight is possible it is not at its best without the rudder.

ParkZone’s new Mustang BL removes many of the earlier Mustang’s performance limitations while adding the option of a Bind N’ Fly (BNF) radio system. ParkZone’s BNF radio system saves you money by taking advantage of the JR or Spektrum transmitter you already own.

The ParkZone Mustang BL meets all the aircraft requirements of the Academy of Model Aeronautics’ (AMA) Park Pilot Program. The aircraft weighs less than 2 pounds (the Program’s upper weight limit) and has a level top speed under 60 mph (the Program’s upper speed limit). For complete Park Pilot aircraft details, follow this link.

The AMA Park Pilot Program offers non-AMA members the opportunity to become AMA members at a much reduced cost. Park Pilot membership includes a great magazine “Park Pilot”, $500,000 personal liability insurance, $2.5 million liability insurance for the flying field owner (see insurance details) and membership in the world’s largest sport aviation association – the AMA. For complete information and details about Park Pilot membership, just click here. 

Photo 1

Photo 2

The BNF Mustang BL incorporates a Spektrum AR500 receiver on 2.4 GHz. This receiver uses the DSM2 technology and is compatible with all DSM2 transmitters such as the Spektrum DX5e, DX6i, DX-7, JR 9303, JR 12X and any JR transmitter converted to 2.4 GHz using a Spektrum module such as the JR 8103 or JR 10X.

Photo 2A

This Mustang BL is bound to a Spektrum DX6i transmitter. The receiver arrives with the fuselage servos connected and the aileron extensions already in place.

Photo 3

Photo 4

In addition to the BNF version of the Mustang BL, there is a Ready-To-Fly (RTF) version available for those without a Spektrum or JR DSM2 transmitter. The RTF Mustang BL version uses the same 27 MHz transmitter as did the original ParkZone Mustang.

Photo 5

In fact, study photo 2 vs. photo 4 and you will note that everything is identical except for the 3-channel transmitter located in the lower left corner of the packed RTF airplane “kit” (photo 5). The item just to the transmitter’s right side is the field charger for the 3-cell 1300 mAh Lithium Polymer (Li-Poly) battery pack.

The included Li-Poly pack is a huge improvement over the original Mustang’s Nickel Metal Hydride (Ni-MH) battery pack. A Li-Poly battery delivers its power more efficiently than does the Ni-MH system. More “power” is available to the 480 outrunner motor even though the voltage is either the same or even slightly less than that of the Ni-MH pack. But in this aircraft, even the voltage is higher at 11.1 Volts. There is a lot more power available in this airplane.

Photo 6

Finally, the BNF Mustang BL version includes all the hardware and instructions needed to install a working rudder on the airplane. The above photo shows the included carbon pushrod, servo linkage and rudder control horn to make a working rudder. You only need to supply a small servo such as the E-flite s75 Sub-micro servo pictured.

The RTF version does not have this option as the transmitter has only three channels. However, should you sometime in the future have a DSM2 Spektrum or JR transmitter on 2.4 GHz, you might wish to raise your RTF Mustang BL to BNF standards by converting to a working rudder and 2.4 GHz performance. If so, the servo linkage is available separately (PKZ1822) for only $7.

Assembly

Photo 8

There really isn’t much assembly needed on this airplane. Activating the rudder does take about 20 minutes and a little knowledge but is well worth the effort. Since much of the assembly work involves attaching the elevator and rudder control horns, it might be best to start by binding the Mustang BL’s AR500 receiver to your transmitter.

Rather than try to install the motor battery and power the receiver using the Electronic Speed Control’s (ESC) Battery Eliminator Circuit (BEC) (replaces the conventional on-board radio system battery pack by drawing current from the motor battery), try this method. Using the BEC during binding means that the motor power circuit is alive and just waiting for someone to accidently hit the transmitter’s throttle stick to high and back which activates the motor.

Therefore, use a separate conventional 4 or 5-cell on-board battery pack, a three-wire JR switch and the usual “bind plug” to bind the receiver to your transmitter. Insert the switch lead into the battery and the receiver. Attach the bind plug to the switch’s “charge” lead. When you turn on the receiver switch, the AR500’s light will blink. Then just hold your transmitter’s bind switch, the “trainer” switch on the DX6i, and turn on the transmitter. The receiver light will go off, return blinking and finally lock on. The binding process is complete.

The wing is already completed, both aileron servos installed and connected, and ready to bolt into place. Since the receiver is already powered up after the binding process, now is a good time to connect the aileron servos to the receiver “Y” cord and make sure they are centered. Have the transmitter’s aileron trim lever in the neutral position and use the mechanical clevises on the aileron control rods to make any adjustments to center both ailerons.  Test fit to the fuselage and then put the wing aside for now.

Photo 9

It is easier to install the working rudder now, before adding the stabilizer. Use a very sharp, new hobby razor knife blade to carefully cut a “V” on two sides two rudder sections. The thin foam part between the rudder and the vertical fin is actually the rudder hinge. Do not cut that.

Photo 10

Pay special note to the bottom “V” cutout in photo 10. I tried to cutout the top “hinge” as shown to match the elevator but just cutting a “V” is best for operational purposes.

Photo 11

Photo 12

I tried cutting out the top hinge itself so I could paint it olive drab and hide the white foam without having to paint the yellow rudder olive drab as well. That worked but was more difficult to do than just cutting out the “V”. The bottom full-size simulated hinge requires the “V” cutout. Actually, the olive paint on the yellow rudder doesn’t look bad at all. The large black control horn effectively distracts attention from it.

Photo 13

Photo 14

Attach a piece of double-sided tape to the bottom of the E-flite S75 servo and insert it into the rudder position next to the ParkZone SV80 elevator servo. Run the control rod through the rear fuselage rudder exit hole as shown

Photo 15

Photo 16

Once the rudder control rod is in place, connect the clevis to the supplied control horn and position it as shown. Then drill two 1/16 in. holes through the rudder and attach the flat screw plate using the supplied bolts through the entire rudder. Connect the control rod to the rudder servo, checking that the rudder is centered and moves in the correct direction. If not, use the transmitter’s reversing and sub-trim functions.

Photo 17

Photo 18

Insert the stabilizer/elevator through the fuselage slot from the right side(seen from rear). Make sure the elevator control horn is on the bottom, gray, side. The control horn will not slide through the fuselage slot requiring it to be inserted from the right. Note the raised mold lines on the stabilizer in photos 17 and 18. There are two more on the bottom. Align all four raised lines against the fuselage as shown. This insures proper alignment.

Photo 19

Four pieces of transparent tape are used to secure the stabilizer in place as shown in photo 19. The tape is nearly invisible except under strong photo lamps. If you wish, a little foam-safe thin CAA can be used on the underside to attach the stabilizer. Only a drop or two on each underside is needed to do the job. The tape works just fine for me.

Neutralize the elevator as was done for the ailerons and rudder. The Mustang BL is now ready to go. The motor battery is a 3-cell, 11.1 Volt Lithium Polymer pack with a capacity of 1300 mAh. This is enough battery to fly for about 8-12 minutes.