Special Hobby 1/48 XF-85 'Goblin'

KIT #

48003

PRICE:

$17.98 MSRP

DECALS:

For both aircraft

REVIEW &
PHOTOS :

Scott Van Aken

NOTES:

Limited run, multi-media kit

HISTORY

During WW2, one of the concerns of the USAAF wasthat of escorting it's bomber fleet to the target and back. While this problemwas allayed in Europe by the Mustang, it was in the Pacific theater where thehuge distances were a real problem for fighter escort. Not until very late inthe war and the taking of Iwo Jima, was it possible to escort the B-29s to theirtarget.

Post war and the distances to the new enemy, theSoviet Union, being even greater, the problem was magnified. The superbomber,the B-36, had tremendous range, however, except for the F-82 Twin Mustang, therewas little that was able to effectively escort the huge aircraft. 

With the changeover to jet aircraft, the F-82would have been hopelessly outclassed and there was no way the fuel-thirsty jetsof the time could have been able to escort the B-36 on any missions. It is inthis climate, that the thought of a parasite fighter was tried. 

This concept wasn't new, in fact, the Russiansthemselves had successfully used a TB-2 bomber carrying I-16 fighters on severalmissions in the Crimea during WW2. However those were bombing missions by theI-16s with the TB-2 carrying them close to their targets and not true escorts,though that is how the whole program was initially conceived.

In the US, the problem was one of having theaircraft small enough to fit into the bomb bay of the B-36. Then, when attackingfighters approached, the escort would be air launched to fend them off and thenreturn to the B-36 for refueling and rearming for another mission.

The result of this concept was the diminutiveXF-85 'Goblin'. The aircraft was basically built around the size of the engineand had to fit in a B-36 bomb bay. Despite these challenges, two prototypeaircraft were built. The were short, a bit tall, and had folding wings to fitinto the bomb bay. Not having to land, no landing gear were needed. A large hookwas developed for the aircraft to grab a 'trapeze' hung from the mother ship.This is similar to the successful F9C Sparrowhawk fighters that were used forthe Navy's airships Akron and Macon in the '30s. 

Using a B-29 mothership, the two prototypesunderwent flight testing in mid-1948. Despite several successful releases andengagements, as well as some that were potentially fatal, the program was notdeemed a success and was terminated in early 1949. Even using the most skilledpilots, the aircraft hookup procedure was quite difficult and it was realizedthat the average USAF pilot would not have the skills needed.

The two XF-85s flew a total of 2 hours 19minutes. Both are still extant. One at the USAF Museum in Dayton, Ohio and theother at the Strategic Air Command Museum just southwest of Omaha, Nebraska on I-80. 

THE KIT

Special Hobby's XF-85 is typical of what we havecome to expect from Czech short run kits. There is one large sprue of light greyplastic containing the styrene parts of the kit. In a bag are the resin partsand in another is a decal sheet. The canopy is thick vacuformed plastic.

Molding on the styrene parts is good, though theedges of almost all the parts are quite ragged and will require a swipe withsandpaper before using. There are only four ejector pin marks and they are onthe inside of the fuselage halves. Detailing is typically superb, with fineengraved panel lines. You may want to rescribe them a bit deeper beforeconstruction as any filling and sanding will undoubtedly make them disappear.

The resin parts are equally well detailed andappear to be totally free of air bubbles. Most of the resin bits are for theinterior, the hook well, intake, exhaust, and the main frame of the groundhandling trolley. There is also a very well done ejector seat for this aircraft.All parts have some sort of block that needs sanded off, but this is typical ofresin parts and should be no problem for most builders.

The decal sheet is very well done, includesserials for both aircraft, and spot on in terms of registration. Typically it isby Propagteam so much care is needed when applying them as they are tissue thinand will stick like limpets. All the small placards are very well done and caneasily be read. A very clear and properly thick vacuform canopy is alsoincluded. Again, I put forward my plea to add a second canopy for those of uswho invariably screw one up. It cannot be that expensive to produce.

Instructions are an 8 page affair in black andwhite. The first page is a small history in four languages. The second a partsbreakdown and explanation of the various colors and warnings. The next fourpages are a six step construction sequence. After reading, it becomes obviousthat there is great deal more scratchbuilding to do with this kit than manyothers. The pitot tubes, the smaller trolley braces, and all the underfuselageskids must be made by the builder. The size of these items are given (inmillimeters) and does not appear to be too difficult, though one does need someplastic card to properly do the skids. The final two pages are for decalplacement and painting. Other than serial numbers, the schemes are the same.Both are natural metal with yellow fin tips and black anti-glare panel.

CONSTRUCTION

You can build any of the variations that this aircraft wentthrough from what is supplied in the kit. I chose the second prototype that wasused in the initial flight phases before both aircraft were taken back toMcDonnell and modified with the winglets and the airflow humps around the hookassembly. If you have seen movies of this plane crashing into the skyhook, thenyou have seen this configuration.

First step is to see how well some of the bits fit together.This means removing the fuselage from the sprue, cleaning up the edges andopenings and test fitting the halves. Not too bad at all. Next it was time tofit the resin cockpit. After a bit of trimming on the fuselage, and multipletest fittings with both halves, the cockpit was superglued into place in theleft side. After a similar procedure, the exhaust cone was also glued into theleft side.

Next the nose intake and hook well were cleaned up andsuperglued together. Don't forget to remove the little bulkhead on the hookwell. After many attempts to get this combo into the nose, I realized that theintake was at a rather large down angle. This wouldn't do. Using superglueremover, I separated the two pieces. Then the nose intake was repeatedly testfit into the nose until it looked pretty good and then it was superglued intoplace. Naturally, the hook well no longer fit and needed to be trimmed back onthe short end until a reasonable fit was attained.

Despite all my attempts at getting a super fit, this just wasn'tpossible and my best efforts will still leave a lot of gaps that need to befilled. This brings from me a common lament regarding these short run kits.Doesn't anyone actually build these things prior to putting them on themarket?  If they did, they would see the horrible fit problems. It is onething to have super detailing and nice resin bits, but it is all for naught ifthe parts don't fit properly.

The fuselage gluing was then started at the very front. I knewthis was going to have to be done in stages to get any sort of good fit and theintake was the worst fit.

I then removed the wings from the sprue to start cleaning them up.WHOA!!! These puppies are not even straight! One is so badly warped that theroot isn't straight. This will be a toughie to repair. Both of them weresubsequently subjected to the hot water treatment in an effort to straightenthem out. Having succeeded at getting them much straighter, they were returnedto the box while more attention was paid to the fuselage. 

Using a combination of regular glue and superglue, the fuselagewas finally cemented together. There were a LOT of gaps in the nose section andhook well area that were initially filled with superglue. Once that was dry, theseams were sanded down and the gaps filled with putty. This took severalapplications  over several days to get it to looking decent. During this time,the interior was painted US Interior green. The instructions say grey, but thisdoesn't sound typical for the era. Photos do show a lighter color than blackfor the cockpit, but since most aircraft of that generation were in interiorgreen, that is what I chose to paint it, using Aeromaster AN1049 InteriorGreen  Enamel. 

While all this was going on, I removed the ejection seat fromthe resin block, sanded the bottom flat and painted it grey using Testor's ModelMaster FS36231. Then the various bits and pieces were painted in accordance withthe kit painting instructions.  Meanwhile, it was time to add on some 'protuberances'to this little egg. First on was the single upper fin. While that was drying, agood hour was spent carefully trimming the vacuform canopy so that it would fitproperly. Then when the fin was good and dry, some filler was added at the rootto take care of gaps. All the flight surfaces were butt joined and all of themhad gaps of varying sized that needed filled and sanded smooth. Each surface wasabout a day in getting done as I firmly believe in letting each coat of fillerdry for a day before sanding. 

Once the central fin was in place and dry, I had a centerline onwhich to base the rest of the flight surfaces. The next ones were the wings. Ifyou recall, these had to be straightened out and it looks like I was successfulin that operation. Once they were firmly in place, the set of control surfacesoutside the central fin were added. The upper fins on these need to be straightup and down when they have finally dried, so keep that in mind while gluing.While waiting for the filler on these to dry, the interior had some of the itemsin it painted flat black or aluminum. Then it was given a black wash and finallydrybrushed with aluminum or light grey. There would have been little wear inthese prototype aircraft. 

Over the course of several days, the remaining fins were gluedin place. It looks very busy back there when all are properly installed. It wasat this time that I cut out the vacuform canopy and carefully trimmed it backuntil it fit properly. Thankfully, the plastic is nice and thick, making it arelatively painless, though slow, procedure.

It was then that I noticed that the front bulkhead did not meetthe bottom of the canopy. Probably a glitch caused when I installed the cockpit,but something that had to be fixed. Using several layers of Evergreen .030 sprueand a file, the bulkhead was built up to the proper height. Then the area wascleaned up and repainted in preparation for finishing the cockpit.

Nextthe control column was glued in place. The instrument panel was painted flatblack and the instrument faces in white. Then Reheat instrument decals were cutand put in the appropriate holes. The references give great instrument panelpics for this step. Once that was done, the panel was glued in place. Finallythe seat was glued in place as was the vacuform canopy,  and the cockpit was done.The canopy needed a bit of filler in a few areas and after that it was masked.The canopy was painted interior green in preparation for having the exteriorcolor put on. But first, the landing skid assembly had to be built.

It was at this time where I generally was not ready to start anyscratchbuilding. This kit had been a bit tough so I set it aside 'for a fewdays' to work on something else. Well, that few days turned into a few weeks. Itwas when I had begun doing a similar scratchbuilding job with another SpecialHobby kit that I decided to do the skid on this one.

First thing I did was to get a nice ruler that had millimeterson it. The skid is supported by two fixtures; one just under the nose and theother about the center of gravity. Each of these consists of two semi-circularplates with a rod between them. The aft fixture also has an additionalreinforcement plate. These bits were cut out of .030 sheet styrene and shaped asneeded. The rod was made from stretched sprue. It isn't very thick, so you needto be aware of that. Actually, the whole deal with the fixtures took about 40minutes.

Then it was on to the skid itself. This is made from two strips,one 4mm and the other 5mm wide. The 5mm one is the longest of the two and needsto have a huge curve in it. Easier said than done. I tried the boiling waterthing, but was unable to get a permanent curve as the plastic is so thin that iteither dissipates the heat too fast, or deforms into a useless lump. What Iended up doing was rolling it around an Xacto knife handle a LOT of times untilthe plastic was more pliable. Then the very front part was glued to the forwardfixture. The instructions are not clear just how this fits; either under, over,or right on the support rod. I fit it to the outside and glued it in place. Onceit had fully dried, the aft bit was glued in place. This gave a convincing curveto it.

Then the small resin wing fences were attached and it was on tothe paint shop.

PAINT & DECALS

All of my metallic paint schemes get an overspray of gloss whiteor light grey. This does two things. First, it fills in those tiny scratchesthat inevitably show up. Secondly, it makes all the surface a constantsmoothness, something that metallic paint schemes need. First step was to paintthe tail tips a very light yellow color. Period color photos of the aircraftshow these fiberglass panels to be this shade. Later, when they were put inmuseums, a more striking red was painted on those pieces, but it never flew withthe tail tips in red. Those were masked and the entire airframe sprayed withFloquil Old Silver over the course of two days. This paint is great, and whiledry enough to gently handle in a few hours, takes 5-9 days to fully cure! Oncecured several panels were masked off and painted in Testors Aluminum Metallizerto give it a bit of character. Last item to be painted was the anti-glare panel.The area around it was masked off and it was painted black. I know you have seenkits with this in OD, but according to the color photos in the references, thiswas black. 

Decals were next and being Propagteam, they were very thin andin registration. I applied them with little difficulty using saliva as a wettingagent. Then I put a drop of Champ on each to ensure they snuggled down. Bigmistake. The Champ ate away a bit at the Floquil paint underneath it. No amountof coverup will fix it barring a repaint. Then I'd need to find another sheet ofdecals. So I oversprayed the entire kit with a bit of thinned Tamiya Smoke whichhelped a bit and made it look less shiny. Live and learn!

Final assembly consisted of drilling holes in the wing tips forthe tip mounted pitot tubes and installing the hook assembly. The hook firmlyfits into a recess in the nose piece. After it is firmly in place, the twoactuating arms are glued on using superglue. These pieces need to be trimmedshorter to fit. Finally the aft nose cover was glued in place after properpainting.

THE TRAILER

The partswere cut from their resin blocks. These are 'I' beams, but frankly, I found itimpossible to remove the resin blocks without damaging the bottom of the beamsso there are no lips on the bottom of the trolley beams. After gluing on thefront yoke to the cross-beam, I then started attaching the two smaller aftbeams. These did not fit well so they and the cross-beam had small holes drilledin them and pins made from paper clip sections installed to facilitate fit. 

Once together the rear wheel assembly was workedon. The wheel halves were glued together and then the support arms were glued toeach side. The wheels are too thick and I would recommend sanding them down asthe arms barely fit the ends of the support beams. One could make plates for theend of the beams for them to attach to, but I just used a lot of superglue. Oncein place, the yoke and front wheels were glued in place. 

Next came the aircraft supports. The small tailsupport fits on the top of the 'A' with two small braces made from sprue. Thelarger front supports needed lots of trimming and eyeballing to fit properly. Iused slower setting super glue to get a good fit on the major A frames beforetrimming the third support. These pieces need to cant inward to support theaircraft. Once they were in the proper position, they were allowed to dry andthey are very sturdy. Small attachment pads are then glued to the top of themand these bits will end up supporting most of the weight of the aircraft.Finally, the tow arm was glued on and the entire thing painted flat black. I didthis to hide the myriad construction goofs I made on the trailer, though theprototype was also black.

Then the completed aircraft was gingerly placed onthe trailer and it was done!

CONCLUSIONS

Frankly it wasn't the easiest kit I have ever built. Itchallenged most of my modeling skills and I still didn't get the canopy properlyfaired in as I would have liked. However, now that it is done, I am very gladthat I built it. The really nice thing about this kit is that you can build theaircraft in any of its various forms. 

I recommend this kit with reservations. One needs to have someof the more advanced building skills under one's belt before tackling a kit ofthis type. The benefit of a successful build is that you will be ready to handlethe greater challenges that lie ahead!

REFERENCES

Airpower magazine, January 1985
Air Enthusiast #52, Winter 1993
Wings of Fame, Vol 7

Review copy courtesy of SquadronMail-Order

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