00-20-1 Chapter 4

The most serious condition indicating an aerospace vehicle, equipment, or SE is unsafe, unserviceable, or non-airworthy and cannot be flown or used until the issue is resolved.

A condition where the aerospace vehicle or equipment may be operated, but not flown or taxied at high speed, to troubleshoot or repair the discrepancy.

Maintenance personnel authorized to clear a Red X must validate all related discrepancies for completeness and accuracy before allowing a vehicle to be flown or equipment to be used.

A condition indicating a lower level of concern than a Red X when there are issues with the aerospace vehicle or equipment. It may require attention, but the vehicle can still be used.

This symbol denotes the least serious condition, indicating a minor issue that doesn't need immediate action.

A set of standardized symbols used on maintenance documents to quickly indicate the condition, serviceability, and status of an aerospace vehicle or equipment.

These symbols are designed to make critical notations instantly apparent to maintenance personnel.

Computer-generated forms symbols printed in black must be overwritten in red to emphasize the importance and urgency of the condition.

When a scheduled inspection cannot be completed due to missing parts, equipment, etc., a 'Red Dash' should be used.

A red symbol on a maintenance document indicating that a discrepancy exists on aerospace equipment, but the actual condition is unknown, making it necessary to investigate further. It is a less severe condition than a Red X.

A red symbol on a maintenance document indicating that a discrepancy exists on aerospace equipment, but it's not urgent enough to ground or stop using it.

A red symbol on a maintenance document indicating that a discrepancy exists on aerospace equipment, but the actual condition is unknown, making it necessary to investigate further. It is a less severe condition than a Red X.

A red symbol on a maintenance document indicating that a discrepancy exists on aerospace equipment, but it's not urgent enough to ground or stop using it. The Red Diagonal usually requires action but doesn't immediately stop usage or flight.

A red symbol used on maintenance documents to indicate that a discrepancy exists on aerospace equipment. The particular condition is unknown and a more serious problem could exist. This symbol is usually used when a piece of equipment needs further investigation.

A red symbol on a maintenance document indicating that a discrepancy exists on aerospace equipment, but it's not urgent enough to ground or stop using it. The Red Diagonal usually requires action but doesn't immediately stop usage or flight.

When a component, assembly, or software change is made to aerospace equipment that could impact flight safety if not installed correctly.

A red symbol on a maintenance document indicating that a discrepancy exists on aerospace equipment, but it's not urgent enough to ground or stop using it. This usually indicates a minor issue that needs attention but doesn't pose a significant safety risk.

A red symbol on a maintenance document indicating that a discrepancy exists on aerospace equipment, but it's not urgent enough to ground or stop using it. This is usually used when a piece of equipment needs further investigation.

When a Red Dash is upgraded to a Red X, maintenance personnel will close out the original Red Dash by adding a remark in the "CORRECTIVE ACTION" block and then re-enter the discrepancy as a Red X in the next open block.

When a Red Diagonal is upgraded to a Red X, it's marked with a line through the original signature, and the upgrading individual's signature is placed above it. A red diagonal line is then added to the symbol.

A trained inspector clears a Red X by filling out the "CORRECTIVE ACTION" block, signing "INSPECTED BY" and "EMPLOYEE NUMBER", and initialing the "SYM" block.

Used if a Red Diagonal is upgraded to a Red X, but not for other symbol upgrades.

When an individual determines that a Red Diagonal is more serious than initially entered, they can upgrade it by drawing a line through the original signature, adding their signature above it, and marking the symbol with a Red X

The individual who accomplishes the corrective action signs off on Red Dash discrepancies by entering their last name initial over the symbol and their minimum signature in the "INSPECTED BY" block.

The individual who accomplishes the corrective action signs off on Red Diagonal discrepancies by entering their last name initial over the symbol and their minimum signature in the "CORRECTED BY" block.

Symbols on AFTO forms are a definitive record of the aircraft's condition and cannot be erased under any circumstances.

If the GP/CC or a designated individual clears a Red X at a location where qualified maintenance personnel are not available, they must annotate the name of the GP/CC and the specific repair action in the "CORRECTIVE ACTION" block.

When a DFT/CFT clears a Red X, they can only clear the portion of the work they have completed, and only if authorized by the dispatching organization.

A symbol entered in error must be corrected by entering a statement in the CORRECTIVE ACTION block, followed by appropriate signatures and initialing over the symbol.

An initial entered in error does not require an additional initial over the symbol. Instead, a specific statement is entered in CORRECTIVE ACTION block explaining the error.

A discrepancy entered in error cannot be erased or changed by anyone except the originator. The individual discovering the error enters a statement in CORRECTIVE ACTION block.

Red X, Red W, or Red Diagonal entered in error must be corrected by entering minimum signature in the CORRECTED BY or INSPECTED BY block, as applicable, and initialing over the symbol.

Erroneous MIS entries must be deleted, not signed off as entered in error. Notify Plans and Scheduling or the appropriate computer system administrator for deletion.

An aerospace vehicle with a Red X can be downgraded to a Red Diagonal for a one-time flight under tightly controlled conditions. This requires authorization and specific documentation.

To downgrade a Red X, the GP/CC or designated official needs to enter a specific statement in the CORRECTIVE ACTION block and sign the INSPECTED BY block.

When a downgrading official is unavailable, the CORRECTIVE ACTION block includes the authorization details and an authorized person can downgrade the Red X by signing the INSPECTED BY block.

After downgrading a Red X to a Red Diagonal, a descriptive statement of the temporary repair or inspection, along with flight restrictions, needs to be entered in the DISCREPANCY block of the AFTO Form 781A.

When an aerospace vehicle arrives at its destination after a one-time flight with a Red Diagonal, the Red Diagonal will be upgraded back to a Red X.

A Red W is used for ICBMs only and indicates a specific type of condition.

An individual discovering an incorrect symbol must enter the necessary information in the CORRECTIVE ACTION block, followed by the appropriate signatures and initialing over the symbol.

The INSPECTED BY block is used to indicate authorization for clearing Red X, Red W, or Red Diagonal discrepancies by qualified personnel.

The CORRECTED BY block allows documentation of the error correction when the individual discovering the error is not authorized to clear the particular symbol.

The Red W symbol on a missile site indicates an inoperative condition that will not prevent a successful launch, flight impact, or command and control of the launch or flight.

A Red W symbol placed offsite indicates a malfunction that will not prevent the operation of a major end item of powered or non-powered SE.

A Red W symbol on a missile trainer indicates a malfunction that will not prevent its operation.

A Red C symbol signifies equipment contaminated by a chemical, biological, radiological agent, environmental, or infestation. This contamination requires attention and specific PPE for operation and maintenance.

The Red C symbol is used to record an event of contamination or infestation in an aerospace vehicle or SE.