Definition
A small adhesive-backed temperature indicator manufactured by Coverite, applied directly to the surface of fabric-covered aircraft skin to measure the temperature of the covering during heat-shrinking. It is used when shrinking polyester (heat-shrink) fabric coverings with an iron, providing a direct read-out of the fabric's surface temperature so the technician can apply the correct shrink temperature without scorching or under-shrinking the fabric.
Plain English
A small thermometer you stick onto aircraft fabric while you're shrinking it tight with a hot iron. It tells you how hot the fabric actually is, so you don't go too hot (which damages it) or too cool (which leaves it loose).
Context Anchor
Seen in aircraft fabric-covering maintenance, especially when checking or setting the temperature of a heating iron.
Derivation
Coverite is the brand name of a company that supplied fabric covering systems and tools. 'Surface thermometer' simply means a thermometer that reads the temperature of a surface it's placed against, rather than the surrounding air.
Why Pilots Care
Proper surface temperature prevents fabric damage or weak bonding during covering work that affects airworthiness.
Intuition Check
Do not think of this as measuring the air temperature in the room. It measures the temperature of the surface it is touching.
Example Sentence 1
Before raising the iron's temperature for the final shrink pass, the technician checked the Coverite surface thermometer to confirm the fabric had reached 350 °F.
Example Sentence 2
He checked the reading on the Coverite surface thermometer to confirm the fabric had reached the correct shrinking temperature.