Accession Number:

ADA021679

Title:

A Review and Analysis of the McDonnell Douglas Collision Avoidance System. Phase II.

Descriptive Note:

Final rept. Jul 74-Sep 75,

Corporate Author:

INSTITUTE FOR DEFENSE ANALYSES ALEXANDRIA VA SCIENCE AND TECHNOLOGY DIV

Personal Author(s):

• Krinitz, Arthur

Report Date:

1975-10-01

Pagination or Media Count:

88.0

Abstract:

The study represents the second phase of IDAs evaluation of the Collision Avoidance System CAS development by the McDonnell Douglas Electronics Company MDEC. The MDEC CAS is an air-derived synchronous system based on timefrequency multiplexing techniques - synchronization timing is disseminated by ground stations and by air-to-air relay among appropriately equipped aircraft. Range-rate measurement accuracies were re-examined because of the design changes, i.e., replacement of doppler measurements with range difference measurements. Synchronization was addressed in some detail to complement the Phase I study. In particular, the limitations imposed by transmitter power, antenna nullsfades, and receiver sensitivity were analyzed in the context of the air-to-air synchronization relay links. Ultimately, the analysis led to the question What happens when there is no synchronization and the asynchronous Back-Up Mode BUM will have to be invoked. For this reason, a portion of the study was devoted to the analysis of the BUM.

Descriptors:

• *AVIATION SAFETY
• *COLLISION AVOIDANCE
• AVIONICS
• SYSTEMS ENGINEERING
• RATES
• TIME
• ERRORS
• THREAT EVALUATION
• TIME DIVISION MULTIPLEXING
• SYNCHRONISM
• RANGE(DISTANCE)
• BACKUP SYSTEMS

Subject Categories:

• Military Aircraft Operations
• Safety Engineering

Distribution Statement:

APPROVED FOR PUBLIC RELEASE