STRATOLINER MODEL RESTORATION
Some time ago I was sent photos and asked to identify a very large, dark, four engined model. It was a Boeing 307 Stratoliner, but the question was also whether it represented a wind tunnel model. Its owner, not deeply into aircraft history or model collecting but impressed by the apparent age, the size (43" wingspan) and weight, had done some research on the subject having contacted Boeing. I thought what the Boeing people had: It was not a wind tunnel model.
Shortly after that, I was given a copy of an article written by O. Phillip Dickert, "Big Ones, Little Ones," published in the April, 1939, issue of Popular Aviation. Dickert, a Boeing model maker, built wind tunnel models for the Stratoliner and described in detail their sizes and construction. Also illustrated in the article is a display model he built of the prototype 307. So it was now verified that the large model in question was never a Boeing wind tunnel model, but it also looked like it was not a Boeing model shop display model either. So where did it come from?
The owner was given the model some years ago by a person who said he found it in an antique store. Further photos sent me verified that the model was quite old and that some markings, specifically windows, had been overpainted by a coat of dark gray paint applied to the whole model. Further, it was obvious that someone had at one time sanded through various layers of paint in order to ascertain what might be found of the original finish. These efforts were rough, and I do not think they revealed as much to that person as my own efforts later when I had the advantage of knowing what I was looking for.
The model was nowhere near me physically, so my early efforts at identifying the model were done by simply viewing photos and researching on the internet. I was helped by a number of persons, Dave Ostrowski (who, at viewing a pre-restoration photo, dubbed it the "Gray Beast"), Steve Remington, Anthony Lawler, John Aldaz, and Francois Renaud who sent me a scan of the large Stratoliner display model found in Thomas Deitz’s book, On Miniature Wings: Models of The National Air and Space Museum. While the dimensions in the book did not quite match our mystery model, I later came to think these dimensions are somewhat off. But this photo was the first indication that the model in question was part of a larger series of models, other examples of which might be extant. The NASM model had been donated to the Smithsonian in 1944 by TWA. Steve Remington came up with more photos of it and ultimately Dave Ostrowski shot a roll of film of the model, now at the Hazy center near the real Pan Am Stratoliner (the original Flying Cloud but now more aptly identified as the Flying Fish). He also recalled having seen a similar model at the TWA headquarters in St. Louis which subsequently disappeared after the sale of TWA to American. (Does anyone know where it is?)
Various sources indicate that TWA spent a good deal of money on its 1940 ad campaign to promote the first transcontinental flights of the Stratoliner. One source opined that TWA had finally pulled itself out of the red by 1939 only to go back into the red because of this expensive ad campaign. It is not difficult to follow Stratoliner items on eBay to discover all sorts of publicity photos, postcards, magazine advertisements, schedules, route maps, menus and other sorts of commemorative items including signed flight club certificates from this campaign. Samuel Vance told me he has a commemorative coin his grandfather was given for being a passenger on the inaugural transcontinental flight. While it is an assumption, it is fairly logical to conclude that these large wood presentation/travel agency models were a part of that ad campaign. Where they were manufactured is not known at this writing, nor how many were produced.
If I could verify that the Gray Beast was of the same series as the other models, then I could confirm its origins and historical value as well as have an idea how to restore it. There were two ways to do this: First, by using Dave’s photos and the minute description of the model he provided to analyze the photos I had, and, second, by actually taking the model apart, removing paint layer by layer to discover what lay under that horrible dark gray final coat of paint. In actuality, I had to pursue the first course of action as far as possible in order to convince the owner that it was worth it to have me take possession of the model to do the second. Both proved fruitful.
The NASM model, while colorful and impressive, is immediately interesting for what it does not include. There is very little engine/nacelle detail. There are no intake scoops or exhaust stacks which are fairly obvious on the actual aircraft, and no attempt to represent the engine fronts which would be fairly well visible on a model this size. On the fuselage, a number of details are absent such as hatch and door outlines, rdf antenna housing, and various intake scoops. The fuselage had been turned and the cockpit windscreen painted on not taking into consideration the flat panes of the actual windscreen that slightly sharpened the outline of the nose. All of these features (or lack thereof) were likewise reflected on the Gray Beast. Further, close ups of the turned nacelles showed identical shapes.
Based on the NASM photos, I asked the son-in-law of the owner to lightly sand the vertical tail to see if there was any evidence of the two red TWA stripes prominently displayed on the NASM model. He was reluctant to get too deeply into the paint, but very soon discovered red in the rudder seam in just the right place. At that point I thought there was little doubt that Gray Beast was a sister ship to the NASM model. The owner agreed, and I was able to pick up the model at his home. I was reluctant to admit to him that I subsequently broke off a wing while trying to get it back to my shop, some two thousand miles distant! This turned out fortuitously as examination showed the wing root had been badly cracked previously and this and the vertical tail had been broken off before. In the event, I completely disassembled the model anyway during restoration.
My first step was to remove paint layer by layer. This proved very interesting and as usual in these restorations, more questions were raised than for which I have found answers.
I started with the tail. Apparent was the fact that its outline was not exactly right. Maybe it once was, but the trailing edge had been badly chipped away. This was true for horizontal tail surfaces as well as trailing edges of wings. As the paint started coming off, I quickly discovered that not all areas had the same sequence of fillers and paints, but it roughly worked out to the following from the original wood up: Tan "plastic wood" type filler at the base of the fin and this was added to in some areas with a reddish brown filler. In other areas a thin, bluish green filler was found. Interestingly, and very puzzling to me, was the fact that filler completely filled in the rudder outline that was cut into the surface obliterating about two thirds of this outline on one side, and about one third on the other. This was done before any primer or paint was applied. Why? I don’t know. Dave had reported that his close-up examination of the NASM model showed that it had been fairly roughly finished. Yet there is no excuse for a professional model being this sloppily finished and I began to wonder if this was, indeed, one of the ad campaign models.
The next coat up was a very thick white paint that was obviously a primer and found in various thickness over all the model. Over this, in places, was more of the red filler, then the silver which I surmised was the original finish coat for this model, as all red markings subsequently found were on this lowest coat of silver paint. And, indeed, in a very thin coat, the two TWA red tail stripes were found. They were hand painted and very faint lines scribed in the silver paint showed how they were laid out prior to painting. Over the original paint job came, in most areas of the tail, a greenish paint and more of the reddish filler, then another coat of silver with more green on top of it in areas. Then a gray coat, and then the very dark gray that was almost black with even more reddish filler. This sequence of paint is confusing, moreso because that reddish filler seems found on almost every coat of paint. Here and at many other places on the model, the fillers all the way down to the basic tan filler had cracked and some areas fallen out. The NASM model also shows some areas of filler problems, and given what I have seen of it in photos, it, too, looks as though a restoration has been done.
Next I went to the wing tops and took off layers. I was looking for the black registration numbers on the bottom silver coat. On the right wing I went down through the layers too fast and found nothing. But the bottom up paint sequence was somewhat different than found on the tail. Lowest was the white undercoat (with fillers around wing root and engines), the original silver, but now a heavy black overcoat before another silver, then black around the nacelles extending back towards the trailing edge, then a dark gray, a green and then on top, the final dark gray that covered the entire model. On the left wing I went slower, convinced that I had missed something on the right wing…and I had! As I got close to the original silver, I started finding straight lines scribed in the paint just as on the tail. I carefully followed these to find most of the outline of the original TWA that had been painted on that wing in large black letters. The black coat that had been applied over the original silver obliterated the TWA insignia, but the scribed outlines verified its original existence.
Later, on the fuselage, I discovered the remnants of the red TWA in a circle under the cockpit on both sides, but no trace of the letters of "The Intercontinental Line" above the windows. The windows were interesting, as well. Each corner was identified by a pin hole, all attached by scribed lines. The "eyebrow" windows on the right side of the fuselage were not found. The larger windows had been painted on a sort of greenish paint that was on the last, not the first silver coat of paint. They might have also been on the first coat, as well, but obliterated by the black overcoat. Yet why would only the windows have been painted in on a subsequent rebuild or restoration? And that greenish paint is interesting. TWA Stratoliners were inducted into the Army Air Force during the war and painted olive drab on top, neutral gray underneath. Had this model been repainted in Army colors? However, no remains of neutral gray were found on the bottom and no remnants of national insignia were discovered.
The thickest and the greatest number of paint layers, some 10 of them, were found in the nacelle fronts where an entirely new color was found next to the wood, a very bright blue-green under various other colors in an order not found on the rest of the model.
A final note on the old paint coats and fillers. Just that. They all looked very old, cracked and checked, as if the model had been originally completed, then almost immediately more fillers and more paints were added at just about the same time. That all of this was done in the original model shop is made more likely by the fact that all coats appeared to have been applied by a spray gun. Brush strokes were found only on the markings. Perhaps with the exception of the final dark gray coat (and even that was old), nothing but natural deterioration happened to the model over the last 60 or 65 years.
After having satisfied myself that I had recorded all the layers of paint (what is presented here is but a summary of my underway notes) and learned what I could from them, I removed the rest of the paint down to the original pine from which the model was constructed. I had become a bit disappointed at the sloppiness with which the model had been finished and was still questioning myself if this was a truly professional job. But now I had a chance to see the model before the finish went on. Would it give me a better opinion of it?
With all the paint off, the model was still together with the exception of the left wing. I had noticed before that the wing root posed a perplexing issue: It looked as though the airfoil was upside down. This early B-17 wing had a fairly symmetrical airfoil, but the model presented an almost flat upper surface and a rounded lower surface. If one is to make this mistake with the airfoil, at least do it with the curved side up! I toyed with the idea of reversing the wings and after taking the right wing off and observing the same problem, I decided to do it.
Is this good restoration practice? Bob Mikesh, who wrote Restoring Museum Aircraft, might say no. But I started rationalizing. I had already decided to correct the vertical tail outline to more closely match that of the NASM model, and I began to think that this model might have been a shop prototype for the whole series given all the different paints and fillers applied apparently one after the other early in the model’s existence. The forward fuselage shape was also a bit fat in comparison to the NASM model and true scale outline of the Stratoliner. Other flaws included off center prop shaft holes and the stand mounting hole drilled a full 3 inches forward of the center of gravity. It wouldn’t balance on my working stand unless the latter was clamped to the workbench. The root chord of each wing differed, and the tail end of the fuselage turning was left blunt. I concluded then and remain convinced that this model was a test shot and probably never issued to TWA. It may have been given to a worker or his child and gone into the family attic for many years. Restoring it to its flawed and incomplete state didn’t seem worth the effort, so restoring it to what its maker had intended for it, using the NASM model as a guide, seemed reasonable.
But was I really sure it was, finally, a professional model and a sister ship to the NASM model? My previous evaluations of the likenesses were solidified as I disassembled the model. It had actually been very carefully thought out and designed. The joints of any very large solid model made from only a couple of pieces of wood are going to work and eventually crack and spit out fillers and paint on the seams. Many of the large display models of this period have this problem. I once saw a roomful of the 1946 Bell model shop efforts done in solid wood and beautifully lacquered. Many, if not most of the joints had broken out. A pity. But the Stratoliner model maker, or at least the one who designed it (and I now tend to think of them as two different people), did what had to be done to attempt to prevent this. He designed it with laminated wood, grains running in opposite directions, so small pieces wouldn’t have the strength to move much, and if they did, would work against each other. Thus the larger laminate wouldn’t work that much, if at all, against other laminates.
Taking off the tails, I discovered they were laminated up of three edge glued pieces of pine. The wing had four laminations. The fuselage was particularly neatly done. After I took off the fuselage wing root block, I found that the fuselage was hollow. It had been constructed of four planks of pine glued into a long, narrow box. These planks were themselves laminated out of two thinner planks, grains running in opposite directions. The hole at either end was plugged by a single piece of wood. When turned on the lathe, the resultant fuselage was alive with beautifully patterned grains and glue lines accentuating the graceful curves of the circular sectioned, tear shaped structure. When I saw this, I groaned at the thought of the model ever having been painted in the first place.
Engine nacelles were laminated up of three lifts, as well. This was pre-war America. The designer didn’t have to do this. There was plenty of large stock around. But he designed it properly to last. The machining and gluing of the laminates was neatly and precisely done.
I found that tail surfaces were doweled, glued and nailed into place. Wings were doweled and glued, nacelles nailed and glued. When reassembling the model, I replaced all dowels, deleted the nails and used epoxy glue.
When the model was completely disassembled, it look very much like a late Thirties, early Forties solid model kit. In fact, Strombecker released a model of the Stratoliner right in the middle of the media blitz. I supposed Howard Hughes, who ran TWA at the time, appreciated that.
In the case of the misshapen vertical fin, I separated the rudder and spliced in a wedge of pine forward of it, then brought the top of the fin into shape. The horizontal tail only required a new trailing edge, as did the wings, but its outline was not changed. According to my Paul Matt drawings (corroborated by other small Boeing drawings), the TWA model had several outline problems, including the horizontal tail, but these did not really detract from the overall appearance of the model as did the vertical tail problem. I have no idea what plans the original designer was working from. But in the main, they weren’t that problematic.
Reversing the wings was a bit of a chore. I would not have removed the nacelles except for this. The wing root angle for the dihedral was, of course, now all wrong and when I corrected it, the wing was too short. Since according to the Matt plans, the outboard chord was a bit narrow and the tips had been badly bashed about, I built up a new root section to be placed between the fuselage wing root block and the wing itself and extended the supporting dowels through this and deeply into the wing. This lengthened the wing enough for the outer section and tips to be reshaped to better outline.
I also reduced slightly the diameter of the fuselage forward of the wings to better match up to scale and the NASM model. The mounting hole was moved back to the center of gravity and lined with brass tubing. Missing on the model were the retracted half wheels (main and tail) and all the propellers. These were constructed of wood as on the NASM model.
The model now being fully reassembled, PC Woody, a wood epoxy paste (also makers of PC 7 and PC 11 epoxy pastes), was used for a filler, and the model required quite a bit. When all neatly filled and sanded, I applied a number of coats of Deft clear lacquer as a sealer sanding between every third coat or so. This finish brought out the beautiful grain patterns on the model and convinced me to build a model of the Stratoliner for myself using exactly these same techniques with the same wood. Only smaller! I followed with two coats of Krylon white primer as a base for Krylon silver metallic. When the metallic went on, it proved still a bit rough, so I alternated coats of the Krylon silver with Deft for several coats sanding lightly between. I hadn’t used this technique before, but I think it gave the silver a nice depth.
Dave’s photos of the NASM model also proved helpful for designing and carving the rather Art Nouveau inspired stand for the model. It was built up of 2 x 12 scrap, a dowel and a lot of PC Woody. It has an aluminum rod mounting shaft. The base was finished the same way as the model.
I had acquired a Maquette 1/72nd plastic and resin kit of the Stratoliner simply for the decal sheet. I had hoped to enlarge parts of it as a basis for the decal sheet I had intended to do for the TWA model. But it was, for the most part, inaccurate and I used mainly the Matt drawings as a basis for my markings. The original model had markings and lettering hand painted. Careful examination of the NASM model showed it was pretty roughly done, but still a lot better than my hand lettering skills would have accomplished. A funny note on the NASM model hand lettering: The TWA in a circle under the cockpit windows reveals the painter used up too much room for the T and the W and left himself little room for the A which gets the "squeezed in afterthought" treatment. I guess you could call that "charming," but….
A long time on the computer resulted in a passable
sheet of graphics for the model, and I used a laser copier to print them on a
clear decal sheet.
I did two copies just to make sure, and it was good that I did, for the colors
the laser printer gave me were too thin when applied to the bright silver
surface of the model. This problem was solved by using two layers of decals.
Fuselage windows were sign makers tape (Scotchcal 220 film--really fine material to work with) and
the cockpit windscreens were airbrushed. Everything was given a couple of final
coats of gloss Deft, the propellers attached, the model placed on its stand and
the portraits taken.
Better than new? Yes, probably, given what "new" may have
actually looked like. Not really a "pure" restoration in that sense, but I think
justified. In any event, the model is a genuine survivor from the Golden Age and
represents the promotion of a significant event in American aviation history:
the first transcontinental flights by a four engined, pressurized airliner. It
gains more relevance with the recent restoration and presentation to the
National Air and Space Museum of the last surviving Stratoliner. However, I
remain somewhat perplexed by the typical reaction of people to the model: "Oh,
what a beautiful stand."
Doug Emmons 2005
Addendum: Prior to reassembling all parts, I inserted a "time capsule" into the hollow fuselage that consisted of what I knew of the history of the model, a photograph of the NASM model and photographs of this model up to that point in reconstruction. Anyone who might do another thorough restoration of this model will doubtless be in for a surprise!