This item is discontinued.

GREAT PLANES F4 PHAMTOM II
PRODUCT REVIEW
by Ken Sheppard

I've always liked the solid, menacing look of the McDonnell Douglas Phantom, it's so ... workmanlike and functional - but at the same time, those upturned wing tips and the anhedral tail introduce a graceful soaring element to it's considerable destructive capability A real devil clothed in angel robes, or so it seemed to me!

The Great Planes kit is a builders dream - plenty of wood, no foam, and the difficult curvy bits moulded in ABS! Three full sheets of plans show the considerable thought that has gone into the design and ease of assembly of this beauty - from the interlocking formers / side panels of the fuselage to the slot-together wing jigs used to align the centre section and wing tips. The box is crammed with die-cut ply and balsa sheets, pre-shaped balsa block parts, a huge bag of hardware and those mouldings - it weighs a ton! Which leads me to my first comment - I now know where all the rock hard balsa goes! - personally, I thought the wood selection let this kit down, If I was building it from scratch and selecting my own wood, I would have discarded about a third of the thinner stock. The thicker bits were okay, but below 1/4" they were hard and heavy. It's a big aeroplane (and I knew from the start that I had little chance of staying within the manufacturers target of 9 lb.) I wanted to air test the Sullivan 'Genesys' in flight power system, with strobe, nav. lights, warning beacon etc., further adding to the overall weight - with a mental wing loading getting up into the 30's, I decided to go to the top of the power range and fit a SuperTigre G-75. I also opted to flight test the full-house capability of the new JR XP-642 radio from MacGregor, by fitting retracts and mixing in flaperons - with the anticipated wing loading, I figured that the latter would be an absolute necessity! So, at last, with all the major decisions made, it was time to clear the bench and get down to work!

FOLLOW THE INSTRUCTIONS
And you can't go wrong! Well, it would be extremely difficult to, for anyone with a little experience of building - it's certainly not a beginners model, to build or to fly, as the instructions clearly point out. The very detailed step-by-step photo guide takes all the sweat out of the build sequence and is very thorough and logical in the way the model goes together. A great section of the 48 page manual is given over to the various techniques needed and handy tips required - excellent!

The one piece wing is built in three parts and needs a large flat area for construction luckily, I have a full-size drawing board which doubles as a bench - one could use an internal ply-faced door as an alternative. The fuselage soon gets to be very long and again, a large flat surface is a necessity. The decision whether or not to fit retracts, and if yes, which system - mechanical or pneumatic, needs to be made before starting the wing, so that the operating systems can be planned. Using the rib tabs and the liteply jigs (called crutches, in the booklet) make assembly of a true structure almost guaranteed (nothings 100% foolproof). The tips are built separately, again with a root and tip crutch jig, which ensures built-in washout. The nose profile of the leading edges are sanded to shape and checked against a tip and root plywood gauge, this may sound a little 'twee', but they really do make it easy. Plywood braces at the main spar and at the trailing edge, position the tips at the right dihedral angle to the centre section - an extra bit of care is needed to accurately cut the slots in the rib faces to accept these braces so that the rib profile match and fit is good. Another tip I would impart is not to make the retract wheel wells too small - if they are too tight, any distortion of the undercarriage leg could well jam them, On the full-size, the wheel well is almost square, giving plenty of clearance. On the model, oversize wheel wells aren't going to be noticed, even with the absence of doors.

One slight difficulty that I had with the fuselage was the final fit of the front bulkhead. probably because of the wood selection, again, the fuselage sides were very stiff and needed a lot of force to pull them together to form the nose taper. The front bull-head is made from two laminations of 1/8" ply, the rear one has temporary 'ear' slots to fit the front of the fuselage sides, holding them in whilst the epoxy and glass cloth reinforcing (recommended) is curing. Unfortunately, the force required to pull the sides in, even with dampening the wood with a water spray, pulled the ply 'ears' off of the former.

A final bond was made using two sash clamps and tapered packers to pull and hold the sides in, using the broken off, 'ears' as location check guides. Good job I was using 24 hour epoxy the 5 minute stuff would have had me in a bit of a mess, I think!

I thought very hard about using a 'soft' engine mount to aid noise reduction, This is a serious consideration when using motors at the top end of the power band as the max. diameter prop you can fit, with that nose leg length is 13" - which is a bit on the small side for minimum noise. However, with that slim nose not allowing for any movement of the engine and mount, I took Mick Wilshere's advice (World Engines - Super Tigre distributor [in England]) and fitted a solid aluminum mount, which combined with an APC prop and the quiet silencer on the G-75, should result in an acceptable dB level. The engine mount supplied with the kit is an adjustable nylon one which ended up in my spares box, to be used in something a little smaller and less powerful.

The sheet tail surfaces were straight forward, with just a little reservation about the density of some of the wood used - with that long fuselage, unnecessary weight at the back could cause balance problems (unfounded, it needed tail weight to get the right C of G!).

The use of pre-tapered stock is excellent, keeping planing and shaping to a minimum, I found my Perma-Grit Long Sanding Block a real boon here - it makes sanding large areas a piece of cake and quick too - if you haven't got one, treat yourself (see Ian at Sandown!). Achieving the anhedral tailplane angle is made easy with yet another plywood jig (they really have thought of everything!). The instructions are very clear regarding hinging and fitting of the torque rods and the preformed wire bits were a perfect fit - almost! The rudder torque rod was bent the wrong way, This is a 'z' bend rod with the 'z' ends at 90 degrees to each other, making it a 'handed' item. I found out too late (fitting the fm to the fuselage) that the threaded arm was facing the wrong way for the servo location in the equipment tray. In that situation, I had to cut off the threaded end and make up a brass tube extension to go the other way which was then soldered on in site - not the easiest of tasks but perhaps I should have realized that my torque rod was bent differently to the one shown in the manual photos it pays to check - but then, should you have to?

PLASTIC PARTS
A big factor in the distinctive Phantom 'look' is the beautifully curved intake to outlet nozzle fairings, giving it that slightly 'hunched' appearance. In the kit, these are two-piece plastic mouldings, the main body locating in a slot in the fuselage sides and on the fuselage formers and the front inlets locating against the fuselage side and on a stepped rebate on the main mouldings. The quality of finish of these mouldings is excellent, but to be honest, the fit wasn't 100%, however it can be worked very easily and lightweight filler is a wonderful thing! The only real problem that I had was with the wing seat flange in the main mouldings - couldn't get it to fit! Ended up removing the flange altogether trimming the plastic to match the wing. The fit was good, and then fitting balsa strip edge reinforcement to the fairing skin, between the fuselage formers. This is not explained in the instructions to well but the result in the end is very pleasing. I used Isopon P38 car filler as it is very quick to go off, easy to sand and is reasonably lightweight - you can file panel lines in it too! With these fairings on she really starts to look like a Phantom and the excitement starts to grow! The radio cover / tailpipe assembly at first seems a little daunting, but by trimming on the fuselage, bit by bit, using copious amounts of masking tape to hold it together, and running in medium cyano, a good fit can be obtained. If you want a good finish leave the outlet cones off until After painting!

FIT-OUT AND FINISHING
The hardware pack is very comp and apart from the aforementioned torque rod, fit-out of the radio gear piping, reservoir and micro switch 'Genesys' black box and harness easy - that fuselage is cavernous! extra hatch in the bottom of the just behind the wing, so that I core the 'Genesys' CCU - the Rx and battery are easily accessed by removing the cone fairing, which also gives un( access to the servos, of course. A end, due to the fuel tank being back in the fuselage, I fitted an os Perry pump - whether this is nee, time will tell. I intend to use it initially and then, when the model is sorted, I' disconnect it and fly without. Ground runs indicated that it may not be necessary - but, rather safe than sorry!

I must take time here to sing the praises of Aztec Graphics (formerly Model Insignia) and John de la Roche in particular, I decided from the start that I would finish the Phantom in a scheme other than that on the box artwork (Khaki/brown camouflage), settling on the 'low visibility' dove grey Marines scheme with all the colourful stars, logos and lettering. I got my hands on the decal sheet of the Tamiya 1/32 scale F-4, colour photo-copied it, worked out the enlargement factor for my model and posted the lot to John. Within a couple of days, I received a complete set of the thinnest and nicest vinyl decals that I've seen. Being a little picky, I wanted some of them changed and after a quick call to John, the revisions were on their way back to me! Wonderful decals - wonderful service! (Aztec Graphics have the decals on file, so sets will be available). Aztec are masters in decal 'specials', the prices are very reasonable and can really make your model come to life.

I used white Solartex to cover the model and Ford Dove Grey acrylic car spray - this was a mistake, in hindsight, as the need to fuel-proof the paint resulted in slight 'crazing' on the unsupported fabric areas of the wing (Solarfilm Spectrum proofer) - perhaps I should have used the recommended Dove Grey MonoKote, except that I wanted to add panel lines, which would have to be fuel proofed anyway (that's my story and I'm sticking to it!). The bottom line is that all finished, she looks pretty damn nice!

Balance was achieved by the addition of 1O oz. of lead in the tail cone (that wing loading was on an upward spiral!) - the combination of long nose and larger motor made it inevitable, I guess!

I decide to do the first flights without flaps mixed in, which made setting up the XP-642 Tx dead easy. A tank of fuel was through the Super Tigre without the pump corrected. What a good mannered engine it is. On a 13 x 6" prop, the thrust at the top end, even with the Genesys stealing a couple of hundred revs, is phenomenal. With the pump connected, it didn't take long to establish the correct setting (3/4 turn open, from closed) for the motor to purr evenly at any angle. Sat on the deck, with the prop turning almost invisibly and with all the lights flashing (tip and fm nav. light, top fuselage strobe and flashing belly beacon), she looked just like the real thing if you squinted a bit!

Now all I needed was a nice tarmac strip and a pair of max. strength bicycle clips!

FLYING THE PHANTOM!
Enter Denny Dobson, Airfield Movement Co-ordinator of Deenethorpe Airfield, near Corby. This lively acrobatic pilot (he flies a Pitts Special and a Christen Eagle - and anything else he can get his hands on!), is also a keen model flier and general aeronut.

Operating out of Deenethorpe, together with a fleet of microlights, Denny and his partner Sandra are great ambassadors for the sport of acrobatic flying - both full-size and R/C! So, when they heard that the Nexus staff were looking for a suitable strip, the invitation was immediate and enthusiastic.

Unfortunately, the weather on the chosen day (decided by a deadline), was not so co-operative! Misty, dull and overcast, it was not the best for a photo shoot (why did I choose a 'low vis' scheme?), but the ceiling lifted sufficiently to go for it.

The SuperTigre was fired up and smoothed out, the retracts given a good pump and the control directions and rates checked - no more excuse!

The take-off run was long and straight with flying speed attained at about 50 yards. Firm up elevator was needed to rotate and she was away! The motor was set a little rich and so wasn't developing ma=um urge but build up of speed was good and she felt pretty solid, I put the gear up and settled down (?) to trim her out. She was a little twitchy in pitch, even with rates on (perhaps a little too much tail weight!), but rock steady in roll. With that wing loading I was going to keep the speed up anyway, at least until I knew her better! I kept the turns large and flat and relaxed a little. Going DE bore up the strip, I was able to bring her down close enough to see that she sits just right in the air with only the silencer breaking her clean lines, she looked absolutely brilliant!

I realized that I was beginning to have fun, banking her over for the camera and lining her up for some 'beat up the strip' low passes. Back to first flight review disciplines!

Taking her up to height and into wind, closing the throttle brought the speed right down and she began to sink (but not as fast as expected) - with no perceptible wing drop either!

I kept the loops large and as scale like as I could and she tracked nice and straight with no tendency to screw out, Bringing her in on finals, I was expecting a fairly short descent, so I lined up for touchdown quite close to me wrong! She floated on majestically (I was holding on a little throttle, I admit,) and with the elevator rates off, not wanting to disturb the twitchy pitch, I let her land herself, with just a little flare at the end. The relief was enormous, with thanks given for a long runway! just to show off, I taxied her all the way back to the start up area and fueled up immediately for the second sortie. This time I stretched the take-off run to what I thought was a scale-like length (it was there, why not use it?) and burnt up some sky, waiting to see if the Velcro attached drop tanks would be pulled off (they stayed on!) and posing for the camera! The flight was curtailed due a loose silencer, and this time I lengthened the approach so that touchdown was pretty well in front of me. Once I get some lead out of the tail and mix in flaps, this bird will really be put through her paces - I can't wait!

PHANTOM-ASTIC!
Love it, love it, love it! My apprehension of excessive wing loading, due to the uninspired wood selection in the kit was not reflected in the flight performance, in as much as the Phantom handled like a lady (a fast lady, to boot!) and with the engine at full chat, performed like a tiger. Great Planes have maintained their high standard of presentation (except forthat darned wood selection), the design plans and instruction manual are just superb. 9 out of 1 0 for Great Planes - would have been 10 out of 10 but ... I'd just love the opportunity to fly a 9 lb Phantom - I bet it would be awesome! Enjoyment level is always a good indicator of a good kit and I have really enjoyed myself with this one - careful building and good, lightweight finishing will present you with a first class machine - I almost feel the urge for a full-blown ducted fan (almost!). - What's next, Great Planes?