Hangar 9’s P-47 20cc

There are ARTF kits and there are ARTF kits. Some require little work and fall together without too much effort or added expense, others are more of a ‘project’, requiring time and patience to complete, along with a few extra purchases. This falls into the latter camp and while that’s not to criticise Hangar 9’s new P-47, you should definitely do your sums before purchase. Has there ever been a time when E-flite or Hangar 9 didn’t have a P-47 in the range? In one form or another it’s the warbird that those brands always seem to produce, but you can’t blame them.

Offering bags of presence, P-47s always seem to fly well, so here’s another, a ‘D’ version, that’s built to 1/7-scale, suits petrol, glow or electric power, has flaps, is retract ready, and includes plenty of nice scale touches. The markings form part of the matt-effect printed covering material and the three sets of decals included offer a little customisation. It’s made using laser-cut balsa and ply and the wings are fully sheeted, along with the profiled stabiliser and fin.

Those extra purchases concern the retracts. You’ll find some oleo struts in the box which seemed a rather strange inclusion as the manual only describes their use with a fixed undercarriage and, let’s face it, barely one in a hundred flyers would seriously consider fixed gear with a warbird. Trailing link oleo struts are used to illustrate retract installation so, without too much thought, I ordered these (£90) and waited a long time before they came into stock. Others have used the struts supplied with their retracts though and, in this respect, the manual seems deliberately obtuse. The retract hard points suit E-flite’s electric units (£125) although, given their cost and scant availability, it’s worth looking for (undoubtedly cheaper) alternatives. In fairness the E-flite jobs fit perfectly and quality isn’t in doubt.

If you’re inclined to push the boat out be aware, too, that a removable hatch covers the fixed steerable tailwheel assembly, so an aftermarket retractable version could be substituted. A few nice surprises lie within the box, not least a neat sunken cockpit with a detailed instrument panel, a good pilot figure, twin pylons and bombs, nice main wheels, a fuel tank, an engine mount, some really nice gear doors, a massive removable top canopy hatch and the sort of build quality that’ll help you forget those extra purchases.

BUILD NOTES

It’s best to have everything ready before you start, not least the retracts, oleos, servos, and extension leads. I bought the suggested undercarriage bits but used my own servos and electric power system components, as I’ll later explain. Assembly is covered thoroughly in the manual, so just requires a patient approach as it all comes together. Paraphrasing the manual is pointless but the following made my notebook:

  • The wing servo mounts are of a size to suit larger mini units so must be opened out if standard servos are to be used.
  • Moulded plastic wing tip lights and covers are provided, although LEDs (not supplied) could be fitted.
  • Flap installations can be fiddly, but not here, the P-47s thick wing provides plenty of room for fitting and adjustment. I used an off-the-shelf Multiplex-plugged loom to neaten up connection at the wing root.
  • Trimming away film for the retracts reveals a factory-fitted moulded wheel well.
  • It’s easy to fit the electric motor stand-off upside-down, so the photos need scrutiny. The part’s open face should be on the underside. Likewise it’s easy to place the drilling template incorrectly, which can lead to all sorts of problems.
  • Cyano seems to have a detrimental effect on the pigment in the matt covering film, so care is required to make sure spillage is avoided.

POWERTRAIN

At a glance, based on the size and weight, you’d assume this is an 8S model, but no, 6S says Hangar 9, and that’s spot-on of course. I had a spare E-flite Power 60 470KV sitting on the shelf and matched it with a Jeti 77A OPTO ESC to spin the suggested 16 x 8” prop. A separate 2S 2200mAH LiPo provides Rx power routed through a PowerBox switch that also regulates the supply. Both 50C 5000mAh and 30C 7000mAh 6S LiPos are suggested.

RCM&E lost a great friend and contributor with the passing of Dave Burton at the end of 2018. Dave had been working on a Black Horse Sea Fury, documenting progress in his Current Affairs series. He’d given a lot of thought to the C of G conundrum that warbirders often encounter when trying to get as much weight up front to balance a short-nose (radial-engine) machine.

In this respect Hangar 9 suggests laying the battery horizontally after the firewall but there are two problems. Firstly, the space available suits a 6S 5000mAh pack, just, but a longer 7000mAh pack is unlikely to squeeze home. What’s more, both packs push far too much weight aft, so in order to hit the C of G range, the model needs added nose weight regardless of the battery used.

Not good. Dave’s solution for the Sea Fury was to take advantage of all that space in front of the firewall and cut a hatch allowing the battery to sit inside the cowl space, a significant alteration that I preferred not to replicate. However, with this cunning idea in mind a solution soon became obvious. The battery tray is retained by screws and removes to reveal a second shelf that’s intended for the ESC. Removing both (the ESC tray must be cut out) reveals a deep cavity that accepts two 4000mAh 6S packs inserted vertically, slap-bang against the firewall. Doing this meant that my model hit the suggested C of G at the mid-range point and, better still, hooking the two packs in parallel doubles the capacity. With that shelf removed my ESC sits within the lower cowl area and benefits from airflow cooling directed by the cut-out in the dummy engine.

FINAL BITS

At 13.5lbs my model scraped past Hangar 9’s 11 – 13lb estimate, but ‘a little more’ never seems to do a warbird any harm. Actually, I’ve known some flyers who add mass to their P-51s and P-47s convinced that doing so improves the flying. Preferring my warbirds clean and mean, I didn’t fit the bombs or pylons (nice as they are) but I may do at some stage. I always fire up a power system early, sometimes to measure the current draw and to get a feel for the amount of urge at my disposal, although I didn’t hook up the wattmeter on this occasion.

A Power 60 and 16 x 8” prop is what you’d call a known combination, one used by E-flite and Hangar 9 in the past, the ’60 is a bit of a beast, so let’s just say that power is in no doubt. An APC-E prop is hardly scale and I’m still searching for a better prop nut that’s in keeping with the full-size, but these things don’t really trouble the eye when this P-47 comes cruising past.

IN THE AIR

Range checks and double-checks complete the wind wasn’t as strong as I would have wanted for the first flights. That may sound strange, but this is no 3lb foamy and a decent breeze, (perhaps 10 – 12mph) helps slow larger / heavier models when it’s time to land. Even on bumpier grass surfaces, she taxis well, progressive throttle is best during the take-off roll and a little elevator keeps the tail down easily enough without the feeling that she’ll leap off the deck sooner than the laws of aerodynamics would prefer.

There’s a slight pull to the left during take-off – a typical warbird trait – but a breath of rudder is all that’s needed to hold the line. The main wheels leave the deck as the tail comes up and a quick climb-out follows. Once airborne you’ll find that this is a lovely model aeroplane. One that instantly feels reassuring, safe and refined. It’s responsive yet predictable. I cruise around at 1/3 to 1/2 throttle whilst pushing throttle all the way delivers the sort of speed that seems almost too much for the scale.

There’s nothing the model won’t do within reason. Big, big loops and fast passes with steep pull-outs are comfortably handled. Rolls can be quite fast although big lazy barrel rolls look and feel far more in keeping and I could just fly lazy passes, climbs and reversals all day long. The speed range is wide and, at the lower end, there’s nothing of concern. Forcing a stall drops a wing for which you’ll need some height to recover but keep it moving and you’ve nothing to worry about.

Those flaps are only needed when it’s time to land and the good news is that deployment doesn’t affect pitch. If the nose does come up then you can assume that the model is travelling too fast and that you’ve selected flap too early. You will need the flaps too, especially on a windless day when you’ll have a fair amount of speed to scrub off. Fail to deploy ‘em and you’ll likely come in too fast risking damage to the retracts. The flaps help when it’s breezier too but throttle may be needed to extend the landing and prevent the model coming down too heavily.

Don’t be tempted to use flaps for take-off, they’re not needed, and run the risk of unsticking the model before it’s ready. Endurance from the 4000mAh packs in parallel is very good. A comfortable 8 – 9 minutes, perhaps a little more if I’m careful with throttle. A pair of 3300mAh 6S packs deliver 6 minutes of flying with enough for another circuit if a landing is aborted. The smaller packs do shift the C of G further aft, but nothing a small elevator trim adjustment won’t cure. 

TOP MARKS

If you’re keen to say goodbye to foamies then this 67” span P-47D should be on your shortlist. It may seem like a considerable investment but you can take comfort from the fact that it’s a ‘sorted’ design that holds no nasty surprises for good intermediate or experienced pilots. Fit a Power 60, a 16 x 8, get the C of G somewhere in Hangar 9’s range and you’ve nothing to worry about and plenty to savour and enjoy.

DATAFILE

Name: P-47D Thunderbolt 20cc

Model type: ARTF scale warbird

Manufactured by: Hangar 9 Available from: www.towerhobbies.eu

RRP: £429.99

Wingspan: 67” (1700mm)

Fuselage length: 58” (1479mm)

Wing area: 825 sq. in.

All-up weight: 6140g (13.5lbs)

Suggested power: 20cc four-stroke or two-stroke petrol engine, Power 60 470KV outrunner

Power system used: E-flite Power 60 (470KV) outrunner, 6S 6600 – 8000mAh LiPo (2 x 3300 – 4000 packs in parallel), 77A ESC, 16 x 8” APC-E prop

Functions (servos): Ailerons (2), flap (2), elevator (2), rudder (1), tail steering (1), throttle (via ESC), retracts (electric)