A new post from “The Drive,” “RQ-21 Blackjack Can Now Strike With Miniature Precision Munitions,” prompted me to take another look at Insitu’s line of Unmanned Aircraft Systems (UAS). The weapons dropped from the RQ-21 are GPS guided, so not of much use against the moving targets the Coast Guard is more likely to be interested in, but the vertical Takeoff and Landing (VTOL) system (also usable with ScanEagle) and the RQ-21 might be useful.

There are of course other competitive systems from other vendors that also might be worth considering but Insitu’s product line is familiar and representative of possible alternatives.

The Coast Guard is currently using Insitu’s ScanEagle UAS on the National Security Cutters. It is a handy size and has good endurance. New photos show that the design has been modified with a third, central vertical stabilizer added. Still, we might benefit from a more capable UAS.

The area a UAS (or any search aircraft) can cover, looking for a moving target, is a function of the speed of the target, the speed of the search aircraft, the effective sweep width of the sensors, and the duration of the search. Greater endurance, higher search speed and greater sweep width generally allow a greater search area.

Better sensors for greater search width or increased fuel for greater endurance may be possible if the payload of the UAS is increased. In addition to the current tailless ScanEagle, Insitu now makes a ScanEagle3 with separate tail surfaces that is claimed to be capable of carrying double the payload.

The RQ-21A is now a standard US Navy UAS. It is in many ways similar to ScanEagle, but it’s an upgrade in speed, endurance, and with its greater payload, potentially better search width without much increase in footprint.

Effective search radius of a UAS may also be limited by the range of its data link but there are ways to obtain much greater range if sufficient payload is available.