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Painting the Eagle III

My painting is 24 inches (61 cm) by 18 inches (46 cm) in acrylic on canvas. For this and my two earlier paintings in 2020 (my first paintings since 1984 or 85) I bought a set of 18 tubes of acrylic paint, some brushes, and canvases already mounted on light-weight wooden frames and coated ready for painting.

It is basically a larger color version of a black and white photo in a magazine. Fortunately, I have access to color photos and some close-ups of the structure and control mechanism. I found some modern color photos on the web of the Cape Cod dunes and beach, which helped with the two shades of sand/earth that seem to characterize the ground there.

Process

I used my large computer monitor, which happens to be the same width as the canvas, to display the source image. In this case, the source image is a composite of two photos. I augmented the main image, a black and white photo in the December 1974 edition of Scientific American, with another (in color) taken from about the same angle. The latter photo, published in Wings Unlimited April-May 1975, includes the tail and more of the wings, but the glider was sitting on the ground, the sail flat and un-inflated.

The ghost image of the glider results from my colored pencil shading prior to painting. I had so many pencil lines denoting tubing edges, wires, and sail panels, I had to do something to clarify it.

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For this painting, I also bought an easel, which needed minor modification to accommodate the fairly deep-edged canvas.

Notice the two wide strips of plastic modeler’s masking tape. I used wide tape because it keeps straighter than the narrower kind, particularly in long strips.

Technical accuracy

Michael A. Markowski’s Eagle III, perhaps better known in the wider world as the Scientific American hang glider and known also as the Princeton sailwing, flew in 1974 and 1975. It featured in the December 1974 edition of Scientific American, the cover of which used an artistic rendering by Ted Lodigensky.

A 1975 color photo of Markowski carrying the folded glider shows that his t-shirt was white and he wore blue flared jeans. (Contrary to Lodigensky’s depiction, the fixed tail surfaces and wing leading edges were dark blue.) I have found no color photo of Markowski’s helmet, but it was a light color; likely white. However, my attempts at painting a white helmet looked unrealistic (I do not know why) so I changed it to red.

A photo of the Eagle III in flight in the Scientific American article shows a shorter keel than the later photos in Wings Unlimited. It seems to me that he lengthened the distance between the wing trailing edge and the tail assembly, likely to provide the elevators with more leverage over the aerodynamic center of the sail shifting longitudinally, causing a delayed ‘positive feedback’ pitching moment, which you do not, repeat not, want. (Been there, done that, got the t-shirt. See Experimental in Three-sixty degree appraisal…) Every photo of the Eagle III in flight that I have seen shows the stick either fully forward (as in my painting) or fully back!

My rendering of the shape of upper surface of the sail results from rudimentary analysis of the structure, aided by a couple of photos showing the upper surface in flight. The sail restraint cables that connect the base of the fin to each trailing edge about a third the way out were likely responsible for some of the rucks in the upper surface. Remarkably, it seems to me, the underside of the sail does not seem to be affected. (I would appreciate any info about it from those who know.)

I thought I had finished it, but looking again at the printed photo in Scientific American, which shows contrast differently from my digitized copy, I realized that I needed to extend the upper surface… Subsequently I also repainted the upper surfaces to better match the photo in Scientific American and, to left and right of what is included in that photo, to better impart an impression of perspective. The latter was mainly guesswork.

Incidentally, the cable from the base of the fin apparently to the control frame top is actually the left trailing edge tensioner. It goes to the left trailing edge, which is out of view, disappearing from our view behind the control frame top bracket. (It had me baffled for a while.)

External link

Scientific American hang glider in Hang Gliding History