What a Group 1 drone actually means

The document to open is Army Techniques Publication 3-01.81, Counter-Unmanned Aircraft System (C-UAS) Operations, dated 23 May 2025. It's approved for public release and free on the Army Publishing Directorate site. I've written about what it puts first. This time I want one table from its first chapter, because nearly every counter-drone headline borrows its vocabulary without its definitions.

What the groups are built on

The manual says it plainly. Drones "are categorized into Groups 1 through Group 5, and this designation is typically based on weight, operating altitude, and speed." Then, in the same paragraph, a caveat that rarely makes it into coverage: the "lines of differentiation between the groups operationally are not rigid." The manual adds that "this ATP focuses on Groups 1 through 3."

Here is Table 1-1, condensed. I rendered the page and read it directly, because the cells merge in ways a text copy scrambles. Altitudes are given as "AGL," above ground level; the table doesn't print a unit, and U.S. military aviation states AGL in feet.

• Group 1, micro/mini: 0 to 20 pounds, under 100 knots, under 1,200 AGL. Threat and commercial examples: DJI Mavic, Enterprise Dual. Friendly example: RQ-11 Raven.
• Group 2, small tactical: 21 to 55 pounds, 101 to 250 knots, under 3,500 AGL. Threat example: SKY-09P. Friendly: ScanEagle.
• Group 3, tactical: 56 to 1,320 pounds, in the same 101-to-250-knot speed cell as Group 2, under 18,000 AGL. Threat example: Shahed 136. Friendly: RQ-7B Shadow.
• Group 4, strategic or theater: over 1,320 pounds, any speed, below 18,000 AGL. Threat example: Forpost. Friendly: MQ-1C Gray Eagle, MQ-1A/B Predator.
• Group 5, strategic: over 1,320 pounds, any speed, above 18,000 AGL. Threat example: Wing Loong II. Friendly: RQ-4 Global Hawk, MQ-9 Reaper.

Look at what's in each column and what isn't. Weight, speed, altitude, and the logistics notes ("hand launched," "requires a runway"). There is no column for warhead, no column for intent, no column for how many people it could kill. The groups describe the aircraft as a thing to be found and hit. They say nothing on their own about what it carries.

Why "Group 1" doesn't mean harmless

The manual's paragraph on Group 1 calls these "mostly" hand-launched, radio-controlled platforms that "are most capable of ISR gathering tasks," meaning intelligence, surveillance and reconnaissance. In the next breath: "Adding weapons to these platforms is possible and can provide significant effects for the adversary." It also notes the tradeoff that the extra weight "will change the range of the aircraft, significantly reducing its effectiveness."

That's the honest shape of it. A small quadcopter with a grenade or a shaped charge is still Group 1, because it still weighs under 20 pounds. The doctrine elsewhere tells planners to "assume that all UAS platforms can be outfitted with different suites of capabilities," including "one-way lethal payloads." The group is a statement about the airframe. Lethality is a separate question.

And the other direction: the Shahed 136, the drone most of the public pictures when they hear "attack drone," is listed in Group 3. Its row-mate on the friendly side is the RQ-7B Shadow, a reconnaissance aircraft. Same group, very different jobs. If a headline says a system "defeats Group 3 drones," that tells you about the size and speed band it was built for. It doesn't tell you whether it was tested against a one-way attack drone or a surveillance plane.

What the groups are actually for

Read the rest of the manual and the reason for the bins comes into focus: they map to what it takes to see and engage the aircraft.

• Detection. The manual says Groups 1 through 3 have low radar cross sections that are "harder to detect by friendly forces' early warning and detection capabilities," and that their low operating altitudes decrease "the likelihood of friendly forces detecting the threat in a timely manner." It's direct about where the gap is: integrated air and missile defense "can effectively counter larger UAS groups, but have difficulty tracking, identifying, and defeating lower class UAS."
• Shooting. The small-arms aiming table is sorted by group. For a crossing target, lead a Group 1 drone by half a football field, a Group 2 by one, Groups 3 through 5 by two. And for the bigger, faster bins: "Do not try to track or traverse your fire for group 3 and above UAS since they fly too fast."
• Equipment. The equipment appendix rates gear by group. A handheld jammer is listed as defending "against groups 1 and 2 UAS," working line of sight against control links at 915 MHz, 2.4 GHz and 5.8 GHz "from approximately 400 meters." A rifle-mounted fire-control sight "can track and hit group 1 UAS up to 120 meters."

So a group is closer to a sizing chart for the countermeasure than a danger rating for the drone. It answers "what sensor, what weapon, what range" before it answers "how bad."

Where my background comes in

I ran counter-IED electronic warfare in the Army. We sorted threats by how they were triggered and how we could reach that trigger, not by how big the charge was, because the trigger is where you can act. The group table reads the same way to me. The notes column for Groups 1 and 2 says they are operated "within line of sight" or "typically line of sight to the ground control station." That's an electronic warfare fact: a line-of-sight radio link is something a jammer can reach, which is exactly why the handheld jammer above is rated for those two groups. It's also why the group label can mislead in the other direction. A Group 1 drone flying on fiber or onboard autonomy is still Group 1 by weight, but the jammer has nothing to aim at. The bin didn't change. The answer did.

How to read a headline that uses the groups

• "Defeats Group 1 and 2 drones." Ask which drones, flown how. The bin covers a toy and an armed quadcopter alike, and the manual itself says the lines "are not rigid."
• "A Group 3 threat." That's a size and speed band from 56 to 1,320 pounds. It spans a one-way attack drone and a reconnaissance aircraft.
• "Small drones are the hard problem." That one the doctrine backs, and for detection and tracking reasons it spells out: low radar cross section, low altitude, launch from anywhere by "a single person or small team."

What I could not confirm

The altitude unit. Table 1-1 gives altitudes as "AGL" with no unit printed. I've read them as feet, which is the U.S. military aviation convention, but the table itself doesn't say so.

Every table cell. The Group 2 and Group 3 speed cell is merged in the printed table (101 to 250 knots spanning both rows), and Group 4's altitude is printed as "< AGL 18,000." I've reported the cells as printed rather than correcting them.

Other services and allies. This is the Army's 2025 manual. Other U.S. services and allied militaries use their own classifications, and I haven't compared them here.

Not my research. I didn't write or test any of this doctrine. My published work is in microwave spectroscopy. Every quotation above is the Army's.

The signal

"Group 1" means a drone under 20 pounds, under 100 knots, flying low. It doesn't mean harmless, and "Group 3" doesn't mean attack drone. The Army's own table puts a Shahed 136 in the same group as its RQ-7B Shadow and says the boundaries "are not rigid." The groups exist to size the defense: what can see it, what can hit it, from how far. When a headline uses one, read it as a description of the airframe, then go find out what it was carrying.