The Hughes XF-11 was an unsuccessful reconnaissance aircraft, only two were built, the remaining 98 on order were cancelled. The first prototype crashed on it's maiden flight, on 7th July 1946, badly injuring pilot Howard Hughes. The second prototype first flew on 5th April 1947 but was rejected by the United States Air Force after testing, as was the competing Republic XF-12 Rainbow.

A model of the aircraft, supposedly of the first prototype, but actually quite different, appeared in the movie “The Aviator”. There is a lot of further history available online, including a few photographs and a newsreel of the crash scene. 

 About 60 resin parts in a segmented bag, come in a strong box.  24! separate propeller blades are supplied, while there is no mention of it in the instructions, I assume that these represent the 16 Hamilton Standard blades of the first prototype, and the 8 Curtiss Electric blades of the second aircraft. There is a vac-formed canopy, nose cone and some small windows.

The decal sheet has four 'stars and bars' with separate red lines, and two pairs of serial numbers. The serial decals for the first prototype, 44-70155, are missing the '1'. The second serial number supplied is 45-54593, not sure what it's for, the second prototype was 44-70156.

The parts are cleanly cast with engraved detail. There are pouring blocks and some flash to clean up. A first examination found plenty of moulding glitches and bubbles. There is a little cockpit detail, some framing detail in the wheel wells, but no engine detail, just a blank plate.

The instructions are a single sheet, with a short history, parts list, and an exploded diagram. There is a single picture of the proposed, earlier XA-37 concept, and a three view drawing with painting and decalling information. The instructions are barely adequate for assembly, extra references will be needed.

 First of all the resin parts were all washed in warm soapy water to remove any mould release oil. The pouring lugs and flash was removed from the main parts, and a little cleaning up done. Lots of sub-assemblies here, each has only a few parts. 

Just to be different, I started construction with the three piece wing. A clean up of the mating surfaces was the only preparation needed. Fit wasn't too bad, with both joints needing a bit of filling with superglue and sanding. Only the upper surface joint needs cleaning up, the lower joint is hidden by the booms.

 I then taped the major parts together to determine what balance weight would be required. The answer was a lot! I filled the fuselage pod, with the exception of the cockpit and nose wheel well with .22 and .38 bullets, then packed as much small shot as I could into the gaps. All held together with superglue. I then assembled the fuselage pod, which was slightly warped, and dealt with the seams.

 After it was all dry, the pod was attached to the wing assembly, with more seams to deal with. A check of the balance found it was close, but still tail heavy, so I put a pair of .22 slugs into each of the engine nacelles, and that did the job. I didn't measure the weight of lead added, but the complete wing and fuselage assembly weighed in at 130 grams, about ¼ lb.

I gave the fuselage pod and wing a shot of primer, to check the seams. Superglue is a great filler, but it's almost impossible to see. A bit more sanding and filling was needed on all the seams, and some glitches and bubbles, using Tamiya basic filler and Mr Surfacer to finish off.

Next to build was the two booms, the usual sanding of the mating surfaces, then joined. Fit was not good, with a seam down the centreline of each boom. More filling and sanding. These seams gave me a lot of trouble, despite superglue and clamping, they kept opening up. I clamped them closed and gave them a soak in very hot water, to try and get a bit of the tension out of the slightly warped boom halves. Gave the booms a prime, and they needed a bit more filling and sanding.

The only remaining sub assembly was the propellers and spinners. Some time was spent sorting through the blades to find the the correct ones for the first prototype, the Hamilton-Standard props at 15'1” diameter front, and 15'3” rear, were a little longer and narrower than the Curtiss-Electric prop at 14'8”, not a lot of difference at 1/72 scale. There didn't seem to be any difference in the blades at all, so I picked the ones with the fewest bubbles or glitches. The instructions were no help in determining the pitch or rotation direction, but I found a good photo showing the forward blades rotating clockwise. All the usual dramas getting the blades right. They had a pin and socket attachment which made things a lot easier then the usual butt joint.

Finally time to get the airframe together. The main trick was getting it all square. I had to do a little sanding of the sockets in the tops of the booms to get the wing to fit better. It was a bit of a juggle getting the tailplane into position at the same time as the booms, locating pins on the tailplane helped hold it together. Then more fun, the boom seams began to open up, sort of lost track about how often this happened, but each part of the seam split open at least once, usually just after I had carefully filled and sanded it. Then the large fins were added, and more seams to deal with. As I was filling the seam on the starboard fin, the top of the boom opened again. More superglue and sanding. Then as I sanded the port fin joint, the boom seam opened again.

I was getting a bit tired of these seams by this point, I had tried three different types of superglue, and had firmly clamped them, not sure what was going on, but anything more than the most gentle handling resulted in the distinctive crack of the seam splitting. Each time needed a clean up of the joint to remove the old glue, a wash, then a sit and dry for a day in the sun.

Eventually I noticed that the tail-plane was slightly warped, about 0.5 mm low in the middle, and that was enough to provide a twist to the booms. I cut the tailplane off, and got rid of the warp using boiling water, then re-assembled. By filling the lower port boom joint at it's open position, instead of clamping it closed, I relieved the stress, and no more splitting; I hope.

Gave the kit another shot of primer, and found a few more repairs to do. The problem with all this sanding is that bubbles keep appearing. Another fill and sand session and I was done. 

On to the cockpit, added the pilot's and observer's seats, instrument panel, control column, periscope and a radio box. It all looked a little bare, and very visible under the large canopy so I added brass harnesses from the spares box. Painted the interior green, then painted some details in a variety of colours to make it look a bit busy. Then I used a foam mask to block off the cockpit well.

Then the u/c legs were added, finally got to see if it was going to tail sit, it was marginal, just nose sitting until my dog walked past, so I filled the well beside the seats with more lead shot. Next step was to add the undercarriage doors, these came in the closed position and needed splitting to display open, and a light clean up around the edges. Sprayed the undercarriage wells Tamiya AS-12 'Bare Metal silver' but had no information on what colour it should be. Then masked off the wells.

Finally ready for a final spray. I used Tamiya AS-16 light grey from a rattle can. The semi-gloss paint showed up a few more seams and bubbles that needed more work, another dose of Mr Surfacer, 1200 type this time, then another sand and wash session. Another coat of AS-16 and I was happy. I then gave the model an overall spray with floor polish. I use a cheap external mix air brush for this, nice even coat, with no bubbles or runs.

Hand painted the anti-dazzle strip to the nose, the instructions show more anti-dazzle patches on the inside of the cowlings, but these did not appear in the photos of the first prototype, so I left them off.

Added the vacformed cockpit. It wasn't very clear, with poorly defined framing lines. Did the one prominent frame with decal stripe.

The supplied decals worked fine, but very slow, and didn't conform to the panel lines. I used micro set to fix them, but found that micro soft didn't seem to do anything, three applications of Mr. Mark Softer did the trick. I used a bit of Xtradecal strip to add the extra '1'. 

Added the radar antenna to the nose, then attached the vac-formed nose cone. Gave the model another spray with polish, then added the wheels and propellers.

A surprisingly big and impressive model, I was kind of expecting something the size of a P-61. With a span of over 100 feet, it's more the size of a four engined bomber. 

Like most resin kits, assembly was quick and easy, but all seams needed a lot of work to get right. The seam splitting issue took a week or two to sort out, but after that things went OK. The separate bladed propellers were a bit of a pain. A build that had it's moments but I'm happy with the finished result. It's the largest resin kit I have tackled.

Recommended for anybody with a few resin kits already done, plenty of swing room on the bench and who don't mind a lot of seam working.

Bill Yenne, 'The World's Worst Aircraft', Bison Books, London, 1990. 

Mike Machat, 'World's Fastest Four-engined Piston-Powered Aircraft',  Specialty Press, North Branch MN, 2011.

http://en.wikipedia.org/wiki/Hughes_XF-11

Kit Instructions.

 Peter Burstow