The Linke-Hofmann was a big bird and stood out like a sore thumb. It used not one but two types of camouflage in order to avoid being seen by the enemy, and in a sense could be considered one of the earlier attempts at “stealth.”
The Linke-Hofmann R.I was designed by—you guessed it—Linke-Hofmann. Interestingly the firm had no prior aircraft design experience. Instead, they designed trains and railcars.
Drawing on wind tunnel data from smaller airframes, Linke-Hofmann assumed that a large bomber with a fuselage that completely filled the space between wings would have some aerodynamic advantages—it is remarkable the design they came up with could get off the ground.
Though no experts in aeronautics, the company had some interesting ideas when it came to concealing a plane in flight.
In order to blend in with the sky, designers at Linke-Hofmann decided to cover the wooden frame with sheets of cellulose acetate, a multifunction transparent film that was used in apparel manufacture and filmmaking. Designers hoped that ground-based observers would see through the plane’s transparent fuselage, which would give the bomber partial invisibility.
Unfortunately, this was not the case. Though cellulose acetate is transparent, it is also very shiny. The sun reflected off the airframe, creating a very noticeable glare that attracted attention rather than minimizing visual noise.
It also didn’t stay clear for very long. Cellulose acetate loses its transparency after exposure to ultraviolet light, turning yellowish color. It’s also not a good structural material. The sheets of cellulose tended to lose their shape or otherwise warp, which caused the wooden airframe to stretch or bend out of shape—making the ungainly bomber more unpredictable to fly.
The next stab at hiding an airplane in plain sight was based on a semi-random assortment of color, the so-called Lozenge camouflage. Lozenge camouflage was a repeating pattern of polygons of different colors, usually four, five, or six-sided.
Like the U.S. Marine Corps’ MARPAT digitally-patterned camouflage, the hope was that the new camouflage design would simultaneously hide the planes from the enemy, and yet be instantly recognizable as a German bomber.
Patterns were created for both day and nighttime missions, with day patterns incorporating red, ochre, and dark green, while night camo tended to favor darker black, dark purple, and grey.
The Linke-Hoffmann R.I was unsuccessful as a bomber. It suffered from a number of design flaws, including a top-heavy design that made the airframe unstable when fuel was low or the bomb bay had been emptied. The cockpit also suffered from a “greenhouse effect” during poor weather or rain, where the cabin windows would become foggy and visibility was severely reduced. Despite the lack of success, the Linke-Hofmann R.I is nonetheless an interesting study in attempts at invisibility, camouflage, and “stealth.”
Caleb Larson is a defense writer for the National Interest. He holds a Master of Public Policy and covers U.S. and Russian security, European defense issues, and German politics and culture.