This radar is poised for dramatic weight loss
By Paul Brinkmann|June 2023
For maximum operational flexibility, tomorrow’s air taxis, delivery and cargo drones will need to detect and avoid other aircraft. Honeywell Aerospace’s path to answering that challenge begins with a radar panel about the size of a paperback novel.
I held one in my hand in April at Honeywell’s Phoenix laboratory. It was surprising that something with so much potential to enable aircraft to fly at night, through clouds or beyond sight of their operators could be packed into such a small volume. At 1.4 kilograms, the unit seemed to have considerable heft for its size and that, it turns out, is an issue. “Our goal is to cut that weight in half,” said Larry Surace, Honeywell’s lead architect for advanced air mobility.
This unit was developed under the company’s RDR-84k program, short for radar, 8 inches by 4 inches (20 by 10 centimeters), along with “K” for K band — the unit’s operating frequency. The goal is to someday sell the coming lighter-weight versions for installation on drones of various sizes, air taxis and other small aircraft. Each will be a “standalone” detect and avoid system, in which algorithms inside the unit determine the locations of other objects. When an aircraft is equipped with multiple panels (up to seven), one will be designated as the lead processing unit to crunch the radar returns coming in from the other six.
To lighten the design, the company plans to incorporate the latest electronic circuitry behind the panel to make the unit thinner and lighter, Surace says. The dimensions of the panel’s face won’t be reduced because that would diminish the field of view. The RDR-84k can be electronically steered to scan 110 degrees azimuth, meaning horizontal, and 30 degrees vertical.
The version that I held has four circuit boards behind the face of the unit, while the next generation is being designed to have two. At Honeywell’s location in Phoenix, engineers and technicians are working on new layouts to do this, a special concern being to dissipate heat, something that’s being aided by new materials.
A 2021 flight test over the Phoenix parking lot proved the collision avoidance ability, when a drone equipped with the RDR-84k technology dodged another drone the company flew directly at it.
When could the half-weight radars be ready? Honeywell isn’t offering a prediction, but intends to provide the technology to manufacturers who would seek FAA certification for their aircraft, complete with the RDR-84k technology.
“It would likely be delivery drones on a last mile trip,” says Taylor Alberstadt, global sales leader for the AAM business unit. “They will need to have the capability to get around a recreational or commercial drone that might be in their path.”