US seeks Arctic-ready UAVs RQ-7 Shadows fail cold weather test

It’s no secret that the United States is on the hunt for an unmanned aerial vehicle [UAV] that is capable of operating in intensely cold conditions. Hopes were pinned on the homegrown RQ-7 Shadows, but unfortunately, it seems not to meet the requirements. 

Reports from Jane’s suggest that the UAV isn’t efficient in icy conditions. Jane’s quoted Lt. Col. James Jones as stating, “The Shadow is not authorized to operate in temperatures below -20ºF.” This statement offers a clear explanation as to why the US Army previously declined to invest in RQ-7 Shadows, Bulgarian Military reported on February 21.

The RQ-7 Shadows had a moment in the limelight during the Joint Pacific Multinational Readiness Center [JPMRC] training rotation 24-02, thanks to unusually warm weather. However, more technological advancement is necessary. The Army is in the market for a new intelligence, surveillance, and reconnaissance [ISR] tool for their brigade commanders. Lt. Col. Jones, Assistant G3 and the officer overseeing operations for the 11th Airborne Division, offered his insight. He suggests that what the Army really needs is a device rated to withstand temperatures as low as -40ºF to be truly practical.

Specific materials

Handling the biting chill of -40 degrees Celsius demands a drone to be designed with specific characteristics. First off, the choice of materials used in crafting the drone should focus on those capable of enduring such severe cold. 

This could mean using highly durable, low-temperature alloys, or perhaps composite materials that retain their form even in the harshest cold. In addition, these materials need to be sturdy enough to stand up to the brittleness often produced by such freezing conditions.

Inconel 718, Stainless Steel and Titanium, or…

When you’re seeking resilient, low-temperature alloys ideal for extreme cold conditions, consider Nickel-based alloys like Inconel 718. These alloys boast superior mechanical durability and excellent resistance to sagging or deformation under persistent stress at low temperatures. Particularly, their widespread use in the aerospace industry bears testament to their reliable performance in icy conditions. 

Another alloy that holds distinction in this domain is Austenitic Stainless Steel, particularly the 300 series. Renowned for its impressive durability, even at cryogenic temperatures, this type of steel is utilized in a multitude of low-temperature environments. From the construction of liquid gas tanks to various other cryogenic storage vessels, its applicability is immense. 

In the realm of high-strength, low-temperature materials, Titanium alloys should not be overlooked. These alloys not only flaunt impressive strength and good low-temperature characteristics, but they’re also lightweight. This combination makes them an excellent choice for aerospace and military applications. A notable example is the Ti-6Al-4V alloy, which remarkably maintains its strength and toughness even at ultra-low temperatures.

… composites

Let’s dive into the topic of composites, specifically Fiber Reinforced Polymers [FRPs]. If your task involves working under cold conditions, FRPs might just be your best bet. By weaving together a polymer matrix and reinforcing it with fibers, these remarkable materials manage to strike a balance between excellent strength and weight ratios, even standing up to chilly environments. 

Moreover, let’s not forget about Carbon Fiber Reinforced Polymers [CFRPs], another notable composite. Loved for their high strength and lightweight, CFRPs don’t compromise their properties in low temperatures. Their impressive credentials have earned them spots in the aerospace industry, where they contribute to the structural integrity of spacecraft. 

Last but certainly not least, we have Glass Fiber Reinforced Polymers [GFRPs]. These are another optimal choice for sub-zero tasks. Known for their incredible strength, lightweight nature, and superior thermal insulation properties, GFRPs rise to the challenge in cold conditions. Overall, they represent excellent options for low-temperature work environments.

Engine, battery, and coatings

Furthermore, the design of the drone’s motors requires special attention to enable them to operate effectively under severe cold conditions. Brushless motors are highly recommended for their exceptional performance and robustness, even under harsh weather conditions. Extra measures like insulation or heating could be implemented to prevent freezing and ensure the motors maintain their functionality. 

Next, the battery setup of the drone should be specifically engineered to work optimally under low temperatures. One possible solution could include a lithium-ion battery integrated with a heater, or perhaps a choice of battery material capable of exhibiting high-performance discharge rates, even at frigid temperatures. To help maintain the battery temperature stable, the battery compartment could also include insulation. 

In addition, you’ll need to consider the choice of coatings applied on the drone; they should be durable under extreme cold. The options could involve low-temperature paint or other coating materials designed to safeguard the drone’s surfaces from frost and ice accumulation. Equally important, these coatings should have the ability to withstand intense UV radiation usually experienced at higher altitudes. Lastly, the drone’s electronics need specific design adaptations to enable them to function in extreme cold conditions.