HELICOPTER RADAR ALTIMETER
Abstract
The altimeter is a pulse radar which measures the time required for the electromagnetic energy to pass from the transmitter to the ground and back to the receiver. The transmitter was originally designed to be used with a terrain clearance radar. The receiver is of the fire control radar type, with the exception ofA LOW GAIN FEATURE. The difference between this altimeter pulse radar and conventional radars is the ability of the radar altimeter to measure time to extreme accuracy. The pulse ringing phase comparison time measuring technique was developed at Bendix-Pacific under a proprietary development. This time measurement technique, under laboratory conditions, has provided short term time measurements to 20 micro-micro seconds. The altimeter design objectives were successfully fulfilled, resulting in an altimeter range in excess of 0 to 5000 ft, an accuracy at touchdown of the helicopter of plus or minus 1 foot, with better than 1% linearity, and a hovering accuracy of plus or minus 1 foot throughout the 0 to 5000 ft range. The altimeter was successfully tested under various conditions of roll and pitch attitude and over different grades and levels of terrain. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 1960
- Accession Number
- AD0255981
Entities
People
- E.e. Nesbit
- M. Ammon
- R.a. Salter