P-47 Thunderbolt

This review was first published in 2006, the kit is still available and remains very popular.

The global explosion in the ARTF market means there’s a wide choice of ‘nearly ready to go’ airframes available – gliders, trainers, aerobatic pattern ships – we’re truly spoiled for choice! There’s good news for modellers with a particular penchant for warbirds, too, indeed there’s a variety of classic designs to be had. Enter Hangar 9’s P-47 Thunderbolt, a semi-scale representation of the American fighter-bomber affectionately nicknamed the ‘Jug’.

The Republic P-47 was originally conceived as a lightweight interceptor but was developed into a heavyweight fighter that made its maiden flight on May 6, 1941. This rugged aircraft flew its first combat mission in April 1943, sweeping across Western Europe. In fact the model featured here reflects the P-47’s European theatre being finished in the silver, black and white markings applied during the invasion of Europe in 1944.

Opening the large, well-decorated box reveals all the major parts neatly packaged in separate plastic bags, and there’s a large hardware package that contains wheels, tank and tail wheel plus all the nuts, bolts, clevises etc. needed to complete the model. A very nice fibreglass cowl is also included, painted in a black and white chequerboard scheme; I thought that the fibreglass was a little on the thin side and worried about its longevity, but time will tell with that. Wrapping up the contents list is the very well illustrated instruction manual, which guides the builder through the assembly in an orderly step-by-step fashion. There was only one omission – no-one is supplied for the ‘hot seat’, so you’ll have to source your own 1/7 scale pilot figure. Leaving the cockpit bare is, of course, unthinkable!

After removing the various components from their respective packaging I examined them for any damage or wrinkling of the covering material, and found everything to be in perfect condition. All the control surfaces are pre-hinged using capillary-type hinges that simply require a few drops of thin cyano’ to anchor them to the airframe. Retracts are similarly pre-installed and only need linking up to a low profile retract servo with the supplied fittings to complete the job. All impressive stuff – a rapid build beckoned!

TO THE LETTER

In true reviewer fashion I decided to follow the instruction manual to the letter and not deviate from the order of assembly. Thus, the first job was to trial-fit the two wing panels using the 1/4” ply wing joiner; the two root ribs interfaced perfectly with no gaps, and the joiner fitted without having to force it – nice! Satisfied with the fit I glued (epoxy) the two halves together and removed the excess using methylated spirit. The ailerons are activated using a servo in each wing panel via extension leads and a ‘Y’ lead to the receiver. With their extension leads fitted (not forgetting to tape the leads together) I screwed the servos into the supplied hatches as directed, which were in turn screwed into their respective wing panels. Draw cords are thoughtfully fitted for pulling the extension leads down to the root, which was easily done. The servos were then hooked up to the ailerons by linkages of threaded rod, clevises and swing keepers, all standard fayer, provided in the kit, and of good quality.

As mentioned, the retracts are activated using a centrally mounted low profile servo, for which I used a Hitec R75. To my surprise, when coupled to the (pre-fitted) retract arms using the parts supplied, the retracts worked straight away, locking in the ‘down and retracted’ position with no adjustment necessary at all. Fluke or beautiful engineering? Anyway, all that was needed to complete the wing was to align the ailerons and secure the hinges with thin cyano’.

FUSELAGE

Assembly of the characteristic bulbous fuselage consists of installing the rudder, elevator and throttle servos, engine (a Saito .80 four-stroke in my case), fuel tank, canopy, cowl and a remote glow connector. The rudder and elevator servos are slotted into two recesses at the rear of the fuselage and are connected to the receiver via extension leads, their attachment to the rudder and elevator being made by linkages comprising of threaded rod, clevises and swing keepers. The throttle servo is positioned inside the fuselage, secured to a ply plate and connected to the engine by means of a wire pushrod.

Two metal engines bearers need to be secured to the firewall using bolts and blind nuts; the bearer arms have slots that enable the engine to be positioned the required distance from the firewall (51/8” or 130mm to the prop driver) before being bolted in place. Incidentally, since the fuel tank supplied is typically American (i.e. fitted with only two outlets), I added a third pipe for filling purposes. I’ve never had much success with the two pipe set-up. What’s more, the three pipe alternative eradicates the need to remove the pressure feed from the exhaust in order to fill the tank.

Right then… the cowl! Fitting said item, then, involves cutting the necessary access holes for the exhaust and needle valve assembly. Oh, and the choke lever, in the case of a four-stroke engine! I also fitted a remote glow driver to the cowl at this stage. Finally, it’s secured to the fuselage with four self-tapping screws into hardwood blocks equispaced around the firewall, which again proved nice and straightforward to do.

Now the pilot can make his entrance, my choice here being a 1/7 scale item from Williams Brothers that soon looked at home in his new surroundings. Final detailing was completed by fitting the dashboard (cut from the decal sheet) and trimming / gluing the canopy into position using R/C Modellers glue.

TAIL FEATHERS

Fitting the stabiliser posed no problems – just a case of making sure it was positioned centrally and horizontally in the fuselage prior to removing the covering from the gluing areas and sticking into place (note that the elevator joiner must be fitted into its slot in the fuselage before fitting the stabiliser). When the glue had dried I then trial-fitted the fin in its fuselage slot, again removing the covering as necessary to achieve a wood-to-wood joint before applying any epoxy and checking for a ‘square’ fit. This stage of the build was completed by securing the elevator and rudder via cyano-secured hinges.

BELLY PAN

A fibreglass belly pan is supplied in the kit to blend the wing to the fuselage. Unusually, for Hangar 9, the example supplied was a poor fit in that it was 1/4” lower than the front of the fuselage. To correct this would have meant major surgery to the front of the model so I decided to leave well alone, hoping that its position beneath the aeroplane would render it practically invisible to the wandering eye. Since fitting the belly pan only required the removal of a small amount of covering material before gluing it onto the wing underside, I was able to move quickly on… But wait a minute… there’s nowt left to do!

Complete assembly of the P-47 took 12 hours and the general fit of most of the components proved to very good, with the exception of that belly pan. The suggested C of G is 41/2” (114mm) from the wing l.e. and took a not inconsiderable 23/4 lb of lead to achieve; more than I expected to use but, alas, there seemed to be no alternative!

AIR TIME

After what felt like ages waiting for the weather to change, a suitable day finally arrived at the beginning of June, and the maiden flight beckoned. Happy snapper Alex Whittaker was on photographic duty, and Nathan Farrel-Jones kindly accepted the role as chief test pilot – it turned out to be a busy day for Nathan as he also pioneered my Tiger Moth in the same session.

With final checks made the 13 x 9” prop-shod Saito burbled into life and we were ready for the off. Throttle gently opened, the P-47 tracked straight into wind on the take-off run with just a little rudder to overcome the torque from the Saito and a dab of up elevator to keep the tail down as she accelerated away. At around 30’ Nathan gave a touch more up elevator, whereupon she lifted off comfortably and settled into the first circuit in a very scale-like manner. On flicking the retract switch the starboard leg tucked away nicely, but the port leg stayed proud of its well by about 1/2”; this wasn’t a problem, though, as the leg later locked down for landing and a subsequent tweak of the retract servo clevis now has the leg tucking away beautifully. Some clicks of right aileron trim and a couple of up elevator saw straight and level flight achieved, and Nathan flew a few familiarisation circuits before checking out the stall. This proved to be pretty much a non-event with no tip-stalling tendencies, just a gentle ‘mush’ moments before the nose dropped.

Upping the ante, our man opened the throttle to explore the P-47’s behaviour at speed. He commented that she felt very light and balanced on the controls and was very responsive, inspiring enough confidence to try some stock aerobatics. The Saito .80 proved to have plenty of power when performing big, warbird-type loops, with no tendency to drop off the top of the manoeuvre (not enough power for vertical flight, though). Rolls proved to be very axial, with just a breath of elevator during the inverted phase – very scale-like in speed of execution, too. Inverted flight was easy and low, strafing passes were great fun. After 15 minutes or so Nathan decided it was time to bring her home and called a landing. Retracts extended, the P-47 settled nicely onto the approach, easing onto the strip with a gentle reduction in throttle and touching down to a perfect 3-pointer, concluding a very scale-like overall performance. Our pilot clearly enjoyed the experience, commenting after the flight that he found the model “easy to fly, very stable and highly manoeuvrable.”

CONCLUSION

Summing up, this is a well-presented aeroplane that’s very straightforward to assemble. My only real criticism is the badly-fitting belly pan; all the other components are beautifully made and covered / trimmed to a high standard. I mentioned the thin fibreglass used for the cowl earlier; at time of writing it’s still intact but I have doubts over its longevity… a shame that it wasn’t moulded from thicker material. As far as the retracts are concerned these are still in fine fettle, certainly fit for purpose, rock solid in their wing mounts and showing no signs of fatigue.

The pretty rapid assembly time is a bonus for those who want to get out and fly as soon as possible, though I was a little disappointed at having to add so much weight to the nose. My P-47 ended up at 9 lb 5oz – slightly outside the manufacturer’s recommended 8 – 9 lb. Suitable for the skills of an average club flyer the model is competitively priced so if you’re looking for a fuss-free, realistic warbird then this could well be the one for you.

DATAFILE
Name: P-47 Tunderbolt
Aircraft type: ARTF warbird
Manufactured by: Hangar 9
UK distributor: Horizon Hobby UK
Tel. 01279 641097
www.horizonhobby.co.uk 
Typical street price £204.00 (May 2011)
Wingspan: 65'' (1651mm)
Fuselage length: 51.2'' (1300mm)
Wing area: 5sq. ft. (0.5sq. m)
All-up weight: 9 lb 5oz (4.2kg)
Wing loading: 30oz / sq. ft. (9.1kg / sq. m)
Rec’d radio: 5-channel, 6 servos
Control functions: Aileron, elevator, rudder, throttle, undercarriage
Rec’d motor: .60 – 1.00 two-stroke or .72 – 1.00 four-stroke or Power 60 outrunner