Just over three weeks into the air war in Iran and in terms of crewed aircraft destroyed, the United States and Israel are yet to lose an aircraft to Iran’s previously much vaunted air defences (a US F-35 was struck by ground fire during a sortie over Iran on 19 March 2026, but managed to return to a US airbase).

The same cannot be said of unmanned aerial vehicles (UAVs). Current data from Aviation Safety Network shows that the Israeli Defence Forces (IDF) have lost 13 and the US military eight, while the Italians had one MQ-9A destroyed on the ground at Ali Al Salem airbase in Kuwait on 15 March.

For the IDF, these losses comprise eight Elbit Systems Hermes 900 medium-altitude long-endurance (MALE UAVs, the first of which was downed over Khameni City, Tabriz, on 28 February, and four IAI Heron MALE UAVs. The US Air Force has lost eight General Atomics Aeronautical Systems Inc (GA-ASI) MQ-9A Reaper MALE UAVs. One of these was shot down over Al-Maraqasha in Yemen by Houthi rebels on 2 March and a second over Basra in southern Iraq by Iranian Shiite proxies on 9 March.

Invariably, Iranian social media and pro-Iranian press outlets such as Russia’s TASS frequently exaggerate the numbers of UAVs brought down and their figures diverge significantly from those provided by Aviation Safety Network. For example, on 28 February it was reported that three Hermes 900s had been shot down when in fact only one was destroyed.

Using open-source figures for the cost of the UAVs and factoring in a half weapon load – AGM-114 Hellfire missiles for the MQ-9As and Mikolit guided glide bombs for the Israeli UAVs, the cost of these UAV losses is approaching USD490 million.

The question now facing many military planners and analysts is whether these UAV losses are excessive or are, in fact, to be expected (given that a key premise for using UAVs in the first place is to facilitate missions over hostile territory without endangering the lives of human pilots).

There are three main considerations in this respect: Iranian air defence capabilities, UAV performance envelopes; and previous UAV operational experience/doctrine.

Iran’s air defence capabilities are shared by the Islamic Republic of Iran Army, the Islamic Republic of Iran Air Defence Force and the Islamic Revolutionary Guard Corps (IRGC). Weapon types are numerous but include short-range anti-aircraft artillery (AAA) such as 14.5 mm ZPU-2 and ZPU-4 anti-aircraft guns, 23 mm ZSU 23-2 towed 4 anti-aircraft guns and ZSU 23-4 self-propelled anti-aircraft guns, through the larger-calibre Oerlikon 35 mm GDF-002, M1939 37 mm, Bofors L70 40 mm as well as Soviet-era S-70 57 mm and M-1939 85 mm weapons. Surface-to-air missile (SAM) capabilities include variants of the Russian SA-7 ‘Grail’, SA-14 ‘Gremlin’ and SA-24 ‘Grinch’ manportable air defence systems (MANPADS) as well as Chinese HN-5A and reverse-engineered QW-1 and QW-18 MANPADS, known in Iran as the Misagh-1 and Misagh-2 respectively. There is also the medium-range Shahab Tagheb: a reverse-engineered version of the French Crotale SAM system that can engage slow-moving targets out to a range of 12 km.

Longer-range SAMs in Iranian service include the I-HAWK, S-200 ‘Gammon’, S-300 ‘Gargoyle’ and SA-15 ‘Gauntlet’ (TOR-M1) systems. In addition, the IRGC has its own domestically produced long-range Ra’ad, Khordad, Talaash and Qaem-118 SAM systems. The latter was unveiled in February 2025 and has been specifically designed for the short-range counter-UAV mission. This truck-mounted SAM system features five launchers, while the missile uses multi-mode guidance (radar, opto-electronic and infra-red) and is fitted with a high-explosive (HE) fragmentation warhead. It is thought that the system was used to bring down an IDF Heron on 2 March over Khorramabad. In fact, of the UAVs shot down over Iran, the majority have been downed by the IRGC, primarily due to their superior SAM systems.

Together, these weapons cover the complete Iranian air defence spectrum. Many of the larger, longer-range SAMs are likely to have been neutralised by US and Israeli air and missile strikes during the current Operation ‘Epic Fury’ as well as by IDF strikes in April 2024 and during Operation ‘Midnight Hammer’ in June 2025. The losses of those more complex SAM systems may account for why US and IDF fast jets and high-altitude bombers, combined with effective suppression of enemy air defences (SEAD), have been able operate with impunity over Iran.

However, Iran still retains a significant air defence capability, albeit not as effective as hitherto and that is perhaps why 21 UAVs have been shot down over the past three weeks. The relatively large radar cross-sections and slow speeds that characterise platforms such as the Heron, with its loiter speed of 60-80 KTAS (111-148 km/h), and the MQ-9A, with a loiter speed of 150-170 KTAS (278-315 km/h), Iran’s less sophisticated AAA and SAM systems are presented with a much easier target than fast jets.

The other factor is that, unlike fast jets such as the relatively stealthy F-35, UAVs do not carry countermeasures such as flares, chaff or electronic countermeasures. This poor defensive profile is also compounded by the lack of a pilot who could take evasive manoeuvres when engaged by air defence weapons.

It is also worth considering how previous operational experience has created false expectations. Operating MQ-9As in the far more benign air defence environment that was present over Afghanistan has perhaps led to false lessons being learned about the survivability of UAVs in an air-defence-rich battlespace.

That said, the rate of UAV losses in this current conflict is slowing. From one UAV shot down on 28 February, two each on 1 and 2 March and peaks of five losses on both 3 and 6 March, attrition then fell to cumulative losses of seven over the period from 9 to 19 March.