Aerospace "Secret" Classification Levels

[Signal Witch]

How the U.S. Keeps Its Most Advanced Aircraft Under Wraps


 In aerospace development, especially when we’re talking about U.S. military or intelligence programs there’s a layered system of secrecy that goes beyond the basic Confidential / Secret / Top Secret classifications.

Here’s the general breakdown from the lowest to highest, plus the more exotic compartments that apply to advanced aerospace projects.

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1. Unclassified but Controlled: Even if something isn’t “classified” in the legal sense, it can still be restricted.

• CUI (Controlled Unclassified Information): covers technical data, export-controlled items (ITAR/EAR), proprietary designs, and program details that aren’t for public release.
  
  
• FOUO (For Official Use Only): an older term, now largely replaced by CUI, but still in use in some agencies.
  

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2. Confidential

• The lowest classification level.
  
  
• Unauthorized disclosure could cause damage to national security.
  
  
• Rare for bleeding-edge aerospace; more common in things like maintenance manuals for already fielded systems.
  

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3. Secret

• Unauthorized disclosure could cause serious damage to national security.
  
  
• Covers many developmental systems before they reach maturity.
  
  
• May include older stealth designs, baseline performance data, and limited test results.
  

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4. Top Secret

• Unauthorized disclosure could cause exceptionally grave damage to national security.
  
  
• This is where most active cutting-edge aerospace R&D sits, especially when it involves:
  • Full performance envelopes
    
  • Sensor & signature data
    
  • Advanced propulsion details
    
    
• Access requires TS clearance plus a need-to-know.
  

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5. Special Access Programs (SAP)

• A layer above Top Secret.
  
  
• Information is compartmentalized so that even someone with a TS clearance won’t know the program exists unless read into it.
  
  
• Types:
  • Acknowledged SAP: the government admits the program exists but details remain classified.
    
  • Unacknowledged SAP (USAP): the government doesn’t publicly acknowledge it at all.
    
  • Waived SAP: access is tightly held, sometimes to only a handful of senior officials.
    
    
• Many black-budget aerospace projects live here.
  

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6. Sensitive Compartmented Information (SCI)

• Applies more to intelligence collection methods than weapons platforms.
  
  
• An aerospace program may require SCI if it involves intel sources & methods (like recon satellites, SIGINT aircraft).
  
  
• Access requires both clearance and explicit indoctrination into the compartment.
  

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7. “Codeword” & “Need-to-Know” Compartments

• Within SAP or SCI, there may be codeword compartments each with its own access roster.
  
  
• Example: Someone might be read into “Program ALPHA” but not “Program BETA” even though both fall under the same overarching system.
  
  
• Each compartment has a cover name or “nickname” that’s unclassified but meaningless without context.
  

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8. “Black” / “Deep Black”

• Informal terms, not official levels.
  
  
• “Black” programs = funding hidden inside other budget lines, minimal public documentation.
  
  
• “Deep black” = no public acknowledgement, existence known only to a very small number of cleared individuals.
  
  
• Often combined with multiple nested compartments so that different contractors or even sub-teams only know part of the design.
  
  
  

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How This Looks in Practice for Aerospace Development

• Early concept phase: Often CUI or Secret; involves contractors submitting designs, some unclassified renderings.
  
  
• Prototype & testing phase: Usually moves to Top Secret or SAP; performance, materials, and signatures are closely guarded.
  
  
• Flight testing: TS/SAP, possibly SCI if tied to classified sensors.
  
  
• Operational deployment: Can stay SAP/USAP for years before any public acknowledgment (e.g., F-117 was in service for ~10 years before reveal).
  
  
  
  

[Blackfingers]

Wonderful write up.Thank you :)

[Sky727]

I have been away for over 50 years but has Top Secret Crypto been changed to something else like maybe SCI ? Thanks..

Some seriously paranoid individuals dwell within those security ranks      

[Maxmars]

I have been away for over 50 years but has Top Secret Crypto been changed to something else like maybe SCI ? Thanks..

Some seriously paranoid individuals dwell within those security ranks  [Image: https://denyignorance.com//images/addsmi...rmidor.gif]  [Image: https://denyignorance.com//images/addsmi...hocked.gif]  [Image: https://denyignorance.com//images/addsmilies/wm.gif]

The developers of the "security" framework and policies were all deeply immersed in the new "Détente" lie.
The public perception that we were "de escalating" the tension which wasn't actually gone... just hidden from them.  It's a quandary you know... "pretending" for "appearances" while acting in violence and malfeasance with "deniability" ... it served no one except those who wish to wage war covertly.

I haven't been out of the loop quite as long as you... but I know that it is the "political appointee" that sets up, and takes advantage of the 'secrecy' to hitch profiteering friends and interests to the operations... it is ugly.

What we call paranoia has some benefits when it comes to security... but clearly... there appears to be no "off" switch as long as there is political, or financial profit to be had.  So... 'career' opportunity ho!

The problem with any abuse in this area is that it can't be "reviewed" except by those read into the 'compartment.'  Oh well.... so much for accountability....Commercial associates LOVE this.  I won't even discuss 'taxes.'

[Wild Bill]

Then you get some idiot like me who can waltz into the offices of the high and mighty  , my trade basically gives me a access all areas clearence in buildings , notice that filing cabinets are not locked or desk drawers and passwords are written down close by ikyn .

Just because someone is at the top of the tree at their work does not mean they do not make the  simple mistakes the average office worker would do  .

[Maxmars]

It used to be a troubling thing to me.....

... contractors...

The hole through which we were "hoping" nothing would slip through.

But you know, "the owner is in my country club," or "his sister is an important person"...."lodge brother" la la la

(PS - I would do that... when wed got that part of the delivered narrative to explain a visit... I would whisper out loud.... "la la la" as a reminder to my colleagues listening where you can expect the bullshit to sprout.)

It's always sprouts sideways.

[Moon68]

Still missing a few: various SIGMA classes and TPC material access

[Maxmars]

If we were to even attempt to list out the numerous channels and paths of codification...

We'd be here for a very long time.

Some activities have the unpleasant feature of pertaining to several 'classifications' and 'protections.'

They must be managed diligently... but political appointees are too important for such things as 
self-examination and oversight...  (mostly because of split allegiances with 'friends.')

[sparkgapwizard56]

Then you get some idiot like me who can waltz into the offices of the high and mighty  , my trade basically gives me a access all areas clearence in buildings , notice that filing cabinets are not locked or desk drawers and passwords are written down close by ikyn .

Just because someone is at the top of the tree at their work does not mean they do not make the  simple mistakes the average office worker would do  .

Unless you are a cleared individual wherever you work is breaking SOP badly and has the laziest SSO on the planet

[Sky727]

We had Army, Navy, and the occasional Air Force people working out of our super secret listening and dissemination building (TOC) which was surrounded by Constantia wire and supposedly more than just Claymores if you got off the approved entry and exit paths.. The building was located in an area that was already surrounded by a strong fence, guards, and guard dogs at night.

There were modern barracks and the all important Officer's club etc etc in the many acres that Ramasun Station encompassed. Our Technicians could listen to taxi cab drivers in New York city USA even though they were located in Thailand. My unit was stationed there as an aviation asset flying and gathering Intel over Cambodia, Laos and Viet Nam. This was early 70s so go figure where how far the technology has come since then. The best Pool/Snooker player stationed at Ramasun was a never admit he was CIA GS (99 ?) who could consistently run two full racks of balls in straight pool ... I played him many a game but alas I won very few if any.

Now to the heart of the write up.. Inside the dissemination building in his own office an individual (do not remember his rank) left some SI material on his desk while he walked down the hall to go to the bathroom. It just so happened our Gestapo S2 walked buy the guys office and saw the material on the guys desk...Poof he was escorted out of the building and lost his TSC clearance thus gone from Ramasun and the military shortly there after. 

A Captain told his wife the reason he was so happy was he thought we had saved someones life today ( our efforts had stopped an assassination in Laos) and as wives tend to talk "Poof" he was also gone from Ramasun and the military.  There are other stories but .....

USA was not in Laos yet most of our missions were in Laos monitoring the Chinese anti-aircraft battalion and other things they had stationed along the road they were building to Vientiane Laos. No dog tags and no personal effects were allowed to be carried during our missions which was stupid but those were the rules. 

The road unlike most things Chinese is still in use today. 

Wow I actually found a video of Ramasun... I worked there for over a year and finally transferred in country to fly other more enjoyable missions. I actually flew into Viet Nam on the Friday before the Monday it fell and picked up the Ambassador's wife, birdcage, and two kids and took them to Bangkok for their safety unlike the 1000s who had been promised a safe evacuation but were left behind.  

I got out in 1977 (could have stayed in and was offered a job (still had my TSC clearance) to go fly helicopters and fixed wing aircraft in central and south America for uncle sugar. I turned down the GS 12 to start as I did not want to ever put myself in a position where TPTB could cut and run if things got inconvenient. In the military your fellow troops would do everything to pull you out of trouble until they were ordered to back off by some REMF .. 




The place has certainly seen grander days ! The Airport in Udon is part Royal Thai Airforce (mostly a fighter wing or 2 of F-16s ) and part civilian traffic and Airliners on the other side of the runway. Back in 73 it was mostly US Airforce F-4s and us flying missions everyday. They even have  Golf course there which if the current commander plays golf is kept in decent condition however, if commander does not play the golf course sucks.