Flaps and Seals and Project HTLingual
The term “flaps and seals” is derived from the original opening-and-resealing procedure used to open surreptitiously letters and dispatches inside either a flapped envelope or folded and fastened with a wax seal.
Also known as the “kettle and stick” method, “flaps and seals” is an Agency tradecraft term for the secret opening, examining, closing, and resealing of envelopes and packages without the knowledge of the recipient.
These techniques were used by the CIA and FBI to gain access to important documents without the knowledge of the sender or receiver. They require great skill and attention to detail in order to be successful and prevent any evidence of tampering. The techniques were used to ensure the safety of confidential documents and to gain access to valuable information.
Flaps and Seals
During the 1950s, the Central Intelligence Agency (CIA) created a special course taught by the Agency’s Office of Technical Services (OTS) to teach field officers the art of opening mail without detection. This course, part of the cover name HTLINGUAL, a CIA mail-intercept project that lasted for 20 years, was used to provide officers with the tools and techniques necessary to open mail without detection.
Officers attending the course learned to open envelopes by softening the glue with steam from a tea kettle, and then easing the flap open with a narrow implement. Field officers often carried a flaps-and-seals briefcase containing tools used in the surreptitious opening of mail. Those tools include an electric heat table with a temperature gauge, blotting paper, sticks, brushes, and gloves, as well as containers of water, glue, and other chemicals.
The three most common techniques used in flaps-and-seals work were steam opening, dry opening, and wet opening. Steaming was usually the most effective.
The Dry Openings Technique
The Dry Openings technique is used to open an envelope without leaving any trace of tampering. It involves carefully cutting away the envelope flaps, leaving them intact, so that the envelope can be re-sealed without detection. This process is often used when attempting to inspect documents without leaving any evidence.
The Wet Openings Technique
The Wet Openings technique involves soaking the envelope in water and then using a tool to carefully open the envelope, without damaging it. This method is most commonly used to gain access to sensitive documents.
The Steam Openings Technique
The steaming open of flapped envelopes is one of the oldest methods of gathering intelligence. British intelligence operatives actually perfected the technique prior to World War II and began teaching special agents of the Federal Bureau of Investigation (FBI) how to get into the mail of Axis diplomats. The British technique is referred to as “chamfering.”
The Steam Openings technique is used to open an envelope without leaving any trace of tampering. It involves using steam-heated tools to carefully open the envelope without damaging it. This method is often used when attempting to inspect documents without leaving any evidence.
The Steam Openings technique was the most effective. In the 1960s, the Office of Technical Services (OTS) even developed a special letter steamer capable of opening up to 100 letters simultaneously. Unfortunately, the glue in the letter flap would usually harden before the contents could be removed, so the steamer was scrapped.
The Roll-out Method
Other methods of surreptitiously removing letters included tightly rolling a letter inside an envelope using a special set of pincers and then extracting it from the unsealed gap at the top corner of the envelope. The letter would then be replaced by simply reversing the technique. Known as the Roll-Out method, this could be done with all manner of long, thin instruments, including a split chopstick or a pair of knitting needles.
The Re-Sealing Technique
The Re-Sealing technique is used to close the envelope after it has been opened. This process requires great skill and attention to detail as the envelope must be re-sealed perfectly to prevent any evidence of tampering.
The Traps Technique
The Traps technique is used to inspect an envelope without leaving any trace of tampering. It involves using a tool to insert a small device, such as a wire, into the envelope to detect any tampering.
Project HTLingual, also known as HGLinguan was originally codenamed Project SRPOINTER (original source), sometimes also known as Project SGPOINTER (original source). It operated between 1952 and 1973.
Originally the project was intended to target foreign diplomats and agents, especially from China and the Soviet Union. However, it was soon used to target domestic peace civil rights activists such as Martin Luther King.
The CIA examined a total of 28 million letters between 1952 and 1973 and opened 215,000 of them.
While the operation allegedly ended in 1973, the government still can open your mail without a warrant.
3 thoughts on “Flaps and Seals and Project HTLingual – 1952 to 1973”
Thank you for this informative information. I just discovered that the Steam Openings technique is used to open an envelope without leaving any trace of tampering, and that it involves using steam-heated tools to carefully open the envelope without leaving any evidence.
I saw in many old films how secret service envelopes are opened.
I never thought that there are so many ways and tools for this.
Very surprised. Very interesting and informative text.
I’ve seen in some articles about this how secret service envelopes are opened. Every time I’ve learned new things that there are so many ways and tools for this. Very interesting and informative text.