Space Cover #221: Fireproof mail
In an effort to improve safety NASA examined everything that could burn in the Apollo spacecraft. This card, postmarked on the launch of the second Skylab crew, has the KSC Official cachet. What makes it interesting is the flame resistant quality of the cardstock. When exposed to fire only the stamp would burn.
While the chance of fire has always been a possibility in spacecraft the painful reality came home to roost on January 27th, 1967. During a plugs out dress rehearsal for the first manned Apollo mission scheduled for February 22, the Prime Crew was killed when a spark ignited under Gus Grissom's couch. Over the preceding year netting, Velcro, and other items that support combustion proliferated like Kudzu. When the electrical short from frayed wires started to burn in the 100% pure oxygen environment pressurized to simulate launch conditions, it created an inferno that could not be contained.
Since the fire happened in the early evening postmarks from that day are scarce. The fire was so intense that the spacesuits melted and fused with the couches. Mysteriously, a paper flight plan somehow survived a conflagration so intense that the spacecraft body over pressurized and ruptured. In response the Command Service Module (CSM) received a major redesign. A quick egress hatch, fireproof spacesuits, and strict rules to separate combustible items from sources of ignition were put into effect. While there is no evidence that fireproof envelopes ever flew in space the covers that were carried were required to be wrapped in Beta cloth, a fine fiberglass like material coated with Teflon that does not burn.
No story of Apollo space covers is complete without mentioning Dr. Mathew Radnofsky and his wife Eunice. They were childhood sweethearts and married for 48 years. After the Apollo Tragedy Dr. Radnofsky focused on spacecraft flammability testing and worked with Papierfabrik Scheufelen GmbH to develop flame retardant paper and Dow-Corning to invent Beta cloth. He also tested postmarks for the Apollo 11 and 15 Moon covers. She was a co-founder of the Johnson Space Center Stamp Club and ran a space cover business for many years. The two of them were instrumental in preparing the FLOWN Apollo covers.
On first glance this cover looks like a NASA Exchange mission emblem envelope postmarked on the Prime Recovery Ship. In actuality, it is the mission patch silkscreened on Beta cloth, trimmed to size, and then glued in place. The artistic whimsy of German graphic artist Detlev van Ravenswaay.
Samples of flame resistant paper travelled to the Moon with the crew of Apollo 12. With hundreds of pages of checklists and reference manuals carried on board a move to fireproof materials would have been welcome. Unfortunately, the paper was not as good accepting ink, didn't do as well when repeatedly folded, and was brittle when exposed to a hard vacuum. While Scheufelen and Radnofsky continued to work on the problem the paper was never adopted. By the time Skylab flew in 1973 the atmospheric mixture was no longer highly combustible.