Student Blog: National Air and Space Museum

​For the past three months I have been interning at the Smithsonian's National Air and Space Museum, and it is not what I expected. This was due partially to the pandemic, but the Museum's unique collection brings up challenges which more traditional museums never encounter. Of course, that is exactly why I wanted to intern at Air and Space in the first place. 

More often than not, conservators work with old materials. Wood, stone, ceramic – humans have used them for so long we know how they age, how they were historically repaired, and how modern conservation treatments might fare over time. Conservators at the National Air and Space Museum have no such luxury. They deal with entire World War II aircraft, or the complex, completely unique plastic and textile layers in a spacesuit. Their collection has literally been to the Moon and back.  

Collections like this fascinate me. Working remotely or in person, I hoped I could contribute to one of these uniquely Air and Space projects. Hopefully something a bit unknown or cutting edge, or something I could sink my teeth into. And boy, did they deliver.  

The objects that have occupied my last three months are aircraft recognition models, used in the second World War to train civilians and soldiers to identify military airplanes. The models are all small, plastic, and painted a matte black with very few details or distinguishing features – essentially the silhouettes of planes. These little planes appear relatively unassuming, especially compared to their life-sized counterparts or the more elaborate models in the Museum's collection. They are remarkable more for their historical significance than their dramatic appearance. That, and the fact that they are literally crumbling to dust before our eyes. 

These models were part of a massive federal effort in aircraft recognition early in World War II. With Japan's attack on Pearl Harbor, the United States was suddenly at war, the Homefront was born, and there was an immediate and urgent need to identify airplanes. Almost overnight, the military needed to train soldiers – and civilians – to distinguish enemy from allied aircraft in a matter of seconds. Aircraft recognition became a major part of the war effort, and models were a critical training component. 

Air and Space has over 800 of these recognition models representing over 220 types of aircraft, Allied and Axis alike, most mass produced by injection molding cellulose acetate plastic. After eighty years, these models are deteriorating spontaneously and catastrophically. The plastic fractures internally, almost as if they shred themselves from the inside out. In the most severe cases the model all but disintegrates, leaving a wing, tail, or stabilizer as the only indication that the object was once an airplane.

​For the majority of my remote internship, I studied the research done by conservation scientists on the models' degradation and tried to apply it to their actual treatment. The aircraft recognition models seem to be victims of their own chemical make-up. Essentially, the additives required to make the cellulose acetate suitable for injection molding in the short term are chemically incompatible with the polymer over time. The shredding is caused by triphenyl phosphate, a liquid flame retardant added during manufacture. Similar to how the freeze-thaw cycle causes potholes in asphalt, this compound crystalizes within the recognition models, causing the disintegration.  

But how can we apply this analysis to the actual object? Is there a way to stop this chemical reaction? Repair the damage? Such a complex and thorny problem will take more time than my ten-week internship, but I was able to do some initial exploration. 

I considered treatment first. What conservation techniques do we have that might stop the triphenyl phosphate from crystalizing? Can we prevent it by controlling the temperature, or coating the plastic? Is it possible to remove the compound entirely? There is little to no conservation research into these areas, and available treatments might damage the plastic in the long run.  

In case treatment was not an option, replicating the models is also a possible method of preservation. The museum world is starting to use replication as a form of preservation, with 3D scanning and printing as an increasingly viable option. I compared case studies, created a survey on conservators' thoughts on replication ethics, and looked into commercial scanning products. 

In addition to my remote research, I was able to work in the Conservation Lab before my internship ended. I treated aircraft recognition models, but models made by hand rather than in factories. In addition to commercially produced plastic models during World War II, the military solicited the help of civilian model makers and boys in high school shop class. The final model I worked on is a wooden North American B-25B bomber, built by William Panagokos in the 1940s, either during his shop class or from a kit available to the public. It felt fitting that my last hands-on project was a model made by another student, and by hand.  

This internship has been a fantastic experience, albeit an unexpected one. Working from home amidst the anxiety of a global pandemic, the pressures and stress of the World War II Homefront resonated in a way they never had before. It was easy to feel some small parallel with William Panagokos as I reversed some old masking tape repairs and reattached the broken wing on his wooden B-25B bomber. 2020 is not the first time our schools, workplaces, and lives have been touched by a global crisis, and I doubt his educational experience panned out how he imagined, either. It was a strangely comforting thought to come from a deceptively unassuming little plane.

— Emily Brzezinski, WUDPAC Class of 2021